Other Common Names
Sulphur-bottom.
Description
Blue whales are the largest living mammals. Though
reports of maximum length and weight vary from one account
to another, Antarctic blue whales are known to have reached
lengths to 100 feet (30.5 m) and weights of over 150 tons
(136,363 kg)[10] before stocks were severely depleted by
whaling operations. North Atlantic blue whales may be
expected to reach lengths of 80-85 feet (24.4-25.9 m). In all
known populations of blue whales, females are slightly larger
than males of the same age.
Viewed from above, the blue whale's rostrum is broad,
flat, and nearly U-shaped (actually shaped like a Gothic arch,
slightly flattened on the tip), with a single ridge extending
from the raised area just in front of the blowholes towards but
not quite reaching the tip of the snout.
The dorsal fin is extremely small [to only 13 inches (33
cm)] and variable in shape from nearly triangular to
moderately falcate. In all cases, it is located so far back on the
animal's tail stock that it is seldom visible until the animal is
about to begin a dive.
Blue whales are light bluish gray overall, mottled with
gray or grayish white. Some animals may have yellowish or
mustard coloration, primarily on the belly, the result of the
accumulation of diatoms during long stays in the cooler
waters to the north. The undersides of the flippers are light
grayish blue to white.
The baleen plates are all black.
Natural History Notes
The blow or "spout" is tall, to perhaps 30 feet (9.1 m),
slender, vertical, and not bushy, as is the blow of humpback
whales, for instance.
Although the blowing and diving patterns of blue whales
may vary, depending on the speed of movement and the
activity of the whale when it is encountered, they may be
generally described as follows: If the animal is moving slowly,
the blowhole and part of the head may still be visible when the
dorsal fin breaks the surface, and the animal may settle
quietly into the water without exposing the last portion of the
tail stock or the tail flukes. If the animal is moving more
quickly, however, or is about to begin a long dive, the
blowhole disappears below the surface, a broad expanse of
the back is exposed and disappears, and the dorsal fin
emerges briefly just before the animal lifts its tail stock and
flukes slightly above the surface before slipping out of sight.
In this species it can be generally stated that the maximum
height of back in the area of the dorsal fin which is exposed
above the surface as the animal sounds is approximately four
times the height of the dorsal fin itself. The exposure of the
tail flukes is unlike that of the humpback whale (Fig. 39), the
right whale (Fig. 50), or the sperm whale (Fig. 57) in that
when beginning a long dive all these other species raise the
flukes high out of the water and usually descend at a steep
angle. Blue whales lift the flukes only slightly, if at all.
Blue whales are relatively shallow feeders, feeding as
they do almost exclusively on "krill" (small shrimplike
crustaceans), most of which are distributed in the surface
330 feet (100 m). Blue whales usually occur singly or in
pairs.
May Be Confused With
At sea, blue whales may be confused with fin whales
(p. 26) and though the two are sometimes difficult to
distinguish from a distance, the following key differences
permit identification at close range:
| Blue Whale | Fin Whale |
|---|
| COLORATION |
| Mottled bluish gray above and below.
|
Gray above, white below; frequently
grayish-white chevron
behind head, right lower
lip white. |
| BALEEN |
| All black.
|
Bluish gray with yellowish-white
strips; front fifth to
third of baleen on right side
all white. |
| HEAD |
| Broad and nearly U-shaped; all dark.
|
Narrower, more V-shaped;
right lower lip white. |
| DORSAL FIN |
| To 13 inches (33 cm); triangular
to moderately falcate; in
last third of back; visible well
after blow. |
To 24 inches (61 cm); falcate;
located slightly more than a
third forward from tail
flukes; usually visible shortly
after blow. |
| SURFACING AND PREPARING TO DIVE |
| Often shows head and blowholes;
broad expanse of back
and much later, dorsal fin. |
Usually rolls higher out of
water, particularly on long
dive; dorsal fin visible shortly
after blow. |
| DIVING
|
| Dives for 10-20 min; surfaces
and blows 8-15 times, making
a series of 12- to 15-s dives
between blows, then disappears
again; sometimes raises
flukes slightly on last dive;
on sounding, the maximum
height of back in the area of
dorsal fin which is exposed is
approximately 4 times the
height of the dorsal fin. |
Dives 5-15 min (most often
6-7); surfaces steeply for 3-7
blows then dives rather
steeply again; does not show
flukes on dive: on sounding,
the maximum height of back
in the area of dorsal fin which
is exposed is approximately 2
times the height of the dorsal
fin. |
| GROUPING |
| Usually found singly or in pairs.
|
Occasionally found singly or
in pairs, more often found in
pods of six or seven individuals;
many pods, consisting of
as many as 50 animals, may
be found in small area. |
See also comparison of fin whale and sei whale (p. 26).
Distribution
Though blue whales have been reported from the pack ice
to Cristobal Harbor, Panama Canal Zone, their normal range
in the western North Atlantic is more limited. In spring and
summer months (about April through at least August) they
can be expected in the northern portion of their range, at
least as far north as the Arctic Circle, feeding on the krill
abundant in those waters. A small portion of the population
may venture north, beyond the Circle. In fall and winter the
population moves south, presumably into temperate and
perhaps to tropical waters. Reliable records include animals
from observations off Long Island and Ocean City, Md.
Though southern limits of the species are poorly known,
there are no records from Florida or the West Indies and no
verified records from the Gulf of Mexico.
Summaries of blue whale distribution based on records
when the species was more numerous indicate that they were
found during spring and summer months in some abundance
on the Nova Scotian Banks, the St. Lawrence Gulf and
estuary, the Strait of Belle Isle, Grand Bank, and in the
waters off the coasts of Iceland, southern Greenland, and the
Davis Straits and Baffin Bay. (Some individuals have entered
the Hudson Strait but not apparently Hudson Bay itself.)
Historically, a few animals apparently appeared off the
coast of southeastern Canada as early as February. It was
speculated that from there a portion of the population
underwent a migration from the Strait of Belle Isle north
through the Davis Straits to the waters off western Greenland.
Some individuals entered the Gulf of St. Lawrence after
the ice was clear and remained behind until as late as November.
In the fall months, certainly by November, the northern
portion of the population had begun retreating to the south in
front of the advancing ice. The remainder apparently also
underwent this migration as well, since blue whales have
historically been nearly absent from Canadian waters during
midwinter.
Many of the migrating individuals were assumed to
continue south to temperate and, less frequently, to tropical
water where they calved. It should be emphasized that
though all of the southward and the subsequent northward
migrations were presumed to be along pelagic routes, details
were poorly documented.
Blue whales have been reported in both shallow inshore
and deep oceanic zones.
Despite considerable attention in the popular literature to
the plight of the blue whale populations and frequent
statements that they are near extinction, blue whale stocks in
the western North Atlantic appear more abundant than has
been usually reported. While present stocks are far short of
previous population sizes, which may have exceeded 200,000
individuals worldwide, they should be sufficiently large for
the species to continue their increase, barring renewed
exploitation.
Stranded Specimens
Stranded blue whales can be readily identified by 1) the
large body size (to 85 feet [25.9 m]); 2) the broad flat head; 3)
the all-black baleen plates (270-395 in number), which are
usually barely more than twice as long as they are wide; and
4) the 55-88 ventral grooves extending to the navel or beyond
(Table 2).
Depending on the state of decay and the position of the
stranded specimen, any of the body characteristics described
for living animals may also be used to positively identify the
specimen.
Figure 9.—Closeup views of swimming blue whales off British Columbia
(top) and Baja California
(bottom). In both photos note the broad rounded
appearance of the head and the single, prominent central head ridge. In the animal on the top note also the black baleen plates, barely visible at the
front of the slightly open mouth. In the animal on the bottom note the pattern of light grayish-white mottling along the back and the raised areas
around the blowholes. These features clearly mark these animals as blue whales. (Photos by R. M. Gilmore [top] and K. C. Balcomb [bottom].)
Figure 10.—The dorsal fins of blue whales may vary from distinctly
triangular (top)
to broadly rounded (middle
and inset) to smoothly falcate
in appearance (bottom). Regardless of its shape, however, the fin is
always located well back on the tail and does not become visible until long
after the animal's blow. (Photos by Japanese Whales Research Institute,
courtesy of H. Omura, mid-Pacific [top]; S. Leatherwood, southern
California (middle and inset); and F. W. True, northern North Atlantic,
courtesy of U.S. National Museum [bottom].)
Figure 11.—A blue whale swimming leisurely at the surface off San Clemente Island, Calif. Note that the blowholes, marked by the raised areas on the top
of the head, are still exposed after the dorsal fin has become visible. Note also the very small size and the shape of the dorsal fin and its position well back
towards the tail. (Photo by S. Leatherwood.)
Figure 12.—A sequence showing fast-swimming blue
whales off southern California. The animal rises rather
steeply to the surface (a),
emits a tall, vertical blow (b,
c),
shows its broad bluish back, mottled with grayish white,
and its small dorsal fin (d,
e), and then dives out of sight
(f). When swimming in this manner, blue whales
sometimes raise their tail flukes slightly above the
surface before beginning their long dives (g). (Photos
by J. F. Fish [a-f] and K. C. Balcomb [g].)
Figure 13.—Two views of blue whales on the ramps of whaling stations in Japan
(top) and at Hermitage Bay, Newfoundland
(bottom). Note the broad
rounded appearance of the head, the single central head ridge, and the dark bluish-gray coloration, interrupted only by mottlings of grayish white. In the
animal on the bottom note the all-black baleen plates, which are very broad relative to their length. (Photos by Japanese Whales Research Institute,
courtesy of H. Omura [top]; and F. W. True, courtesy of U.S. National Museum [bottom].)
Figure 14.—Dead blue whales, harpooned and afloat off the stern of a factory ship in the Antarctic
(top), and on the deck of a whaling station in western
Canada (bottom). In both, note the numerous ventral grooves (from 55 to 85 or more) extending to the region of the navel and sometimes beyond, and the
light coloration of the undersides of the flippers. Even though grooves are often present above the flippers, and occasionally even on the side of the head,
counts of ventral grooves are usually made between the flippers. (Photos by Japanese Whales Research Institute, courtesy of H. Omura [top]; and G. C.
Pike, courtesy of I. MacAskie [bottom].)
Other Common Names
Finback whale, finner, razorback, common rorqual.
Description
Fin whales have been reported to reach 79 feet (24 m).
Females are slightly larger than males of the same age.
The back is distinctly ridged towards the tail, prompting
the common name "razorback" whale.
The rostrum is narrower and more V-shaped than that of
the blue whale and has the same sort of single distinctive head
ridge. The top of the head is flat, though slightly less than
that of the blue whale.
The dorsal fin is up to 24 inches (61 cm) tall; angled less
than 40° on the forward margin, located slightly more than
one-third forward from the tail, and appears on the surface
shortly after the blow.
All individuals are dark gray to brownish black on the
back and sides with none of the mottling present on blue
whales and are rarely as heavily scarred as sei whales. Along
the back, just behind the head, there is a grayish-white
chevron, with the apex along the midline of the back and the
arms of the chevron oriented posteriorly, which is sometimes
distinctive and may be visible as the animals surface to
breathe. The undersides, including the undersides of the
flukes and flippers, are white. On the head, the dark
coloration is markedly asymmetrical, reaching farther down
on the left than on the right side. The right lower lip,
including the mouth cavity, and the right front baleen
(approximately one-fifth to one-third) are yellowish white.
Occasionally the right upper lip is also white. The remainder
of the plates on the right side and all those on the left side are
striped with alternate bands of yellowish white and bluish
gray. The fringes of the plates are brownish gray to grayish
white.
Natural History Notes
Fin whales are one of the most common baleen whale species
in the world and constitute a major portion of the whaling
catch. They are reportedly one of the fastest of the big whales
(sei whales may be slightly faster) possibly reaching burst
speeds in excess of 20 knots, and were not an important commercial
species until the comparatively recent development of
fast catcher boats and the depletion of blue whale stocks.
A fin whale's blow can be from 15 to 20 feet (4.6 to 6.1 m)
tall and has been described as an inverted cone or an
elongated ellipse.
Fin whales dive to at least 755 feet (230.1 m). This depth is
probably deeper than that of either blue or sei whales, a
factor usually reflected in differences among the surfacing,
blowing, and diving characteristics of these three species.
When they are moving leisurely at the surface, fin whales
expose the dorsal fin shortly after the appearance of the
blowholes, slightly later than that of the sei whales. When
they are surfacing from a deeper dive, however, they surface
at a steeper angle, blow, submerge the blowholes, and then
arch the back and dorsal fin high into the air before beginning
another long dive. In this species it can be generally stated
that the maximum amount of the back in the area of the dorsal
fin which is exposed above the surface as the animal sounds is
approximately 2 times the height of the dorsal fin. Fin whales
do not show their tail flukes when beginning a dive.
Unlike blue or sei whales, fin whales do breach on
occasion. When they do leap clear of the water, fin whales
usually reenter with a resounding splash, like that made by
humpback and right whales and not smoothly, head first, as
minke whales often do.
Fin whales are sometimes found singly or in pairs but
more often occur in pods of six or seven individuals and many
pods consisting of as many as 50 animals may be concentrated
in a small area.
Fin whales calve and breed in winter, mostly in temperate
waters.
Atlantic fin whales eat a wide variety of foods, including
krill, capelin, squid, herring, and lanternfish.
May Be Confused With
Fin whales may be confused with blue whales, sei whales,
and, in the southernmost portion of their range, with Bryde's
whales. They may be distinguished from the blue whales by
differences in overall coloration, coloration and shape of the
head, and the size, position, and time of appearance of the
dorsal fin at the surface (see p. 19). After close examination
they may be distinguished from Bryde's whales by the
presence of three ridges along the head (of the Bryde's whale)
and by the smaller, more sharply pointed falcate dorsal fin of
the Bryde's whale (see Fig. 31). They may be distinguished
from sei whales in the following similar ways:
| Fin Whale |
Sei Whale |
|---|
| DORSAL FIN |
| Slightly falcate, forms angle
of less than 40° with back
slightly more than one-third
forward from tail. |
Sharply pointed and falcate:
forms angle of greater than
40° with back well more than
one-third forward from tail. |
| SURFACING BEHAVIOR |
| Usually rise obliquely so top
of head breaks surface first;
after blowing, animal arches
its back and rolls forward
exposing the dorsal fin on the
long dive; on sounding, the
maximum amount of back in
the area of the dorsal fin
which is exposed is approximately
2 times the height of
dorsal fin. |
Primarily skimmer feeders;
usually rise to surface at
shallow angle so that dorsal
fin and head are visible
almost simultaneously; when
starting the long dive does
not usually arch the back as
much as the fin whale; on
wsounding, the maximum
amount of back in the area of
the dorsal fin which is
exposed is approximately 1
times the height of the dorsal
fin. |
| BLOW |
| Tall (to 20 feet [6.1 m]);
inverted cone (point down)
or elongated ellipse. |
Similar shape but smaller—rarely
taller than 10-15 feet
(3.1-4.6 m). |
| DIVING |
| Dive for 5-15 (usually 6-7)
min; blow 3-7 times or more
at intervals of up to several
minutes, then dive again. |
Dive for 3-10 min; usually
blow at even intervals over
long periods of time; often
visible just below the surface,
even on longer dives. |
| COLOR OF UNDERSIDES |
| White higher up on right
than on left side. |
Mostly gray; irregular whitish
area on belly. |
| COLOR OF LOWER LIP |
| White on right, gray on left. | Gray. |
| BALEEN PLATES |
| Right one-fifth to one-third
in front white; all others
alternate bands of yellowish
white and bluish gray; bristles
grayish white. |
Ash black with a blue tinge
and fine grayish bristles. |
Distribution
Fin whales are probably the most numerous and widely
distributed large whale species in the western North
Atlantic.
Fin whales summer from below the latitude of Cape Cod,
Mass., north to the Arctic Circle. (They are frequently seen
between New York and Bermuda this time of year.) Within
this zone they may sometimes be seen very close to shore and
appear to be concentrated between shore and the
1,000-fathom curve from at least lat. 41°20' to 57°00' N. In
recent years they have been reported in relatively large
numbers in the Gulf of Maine from March through June, off
Newfoundland as early as June but increasing to August, and
entering Davis Straits and beyond in substantial numbers in
midsummer to late summer. There is some evidence that the
animals venturing farthest north are the largest individuals
of the species. Movements of the population(s) southward
have usually begun by October, though some fin whales
sometimes remain in the northern seas sufficiently long to
become trapped in the ice and killed.
During winter the range of fin whales spreads out from
the advancing ice southward, reaching at least to the coast of
Florida, into the Gulf of Mexico, and to the Greater Antilles,
though fin whales are not at all common in tropical waters.
During the winter many fin whales move into offshore
waters. Northward migrations probably begin in midspring.
Fin whales may be found in Cape Cod waters all year
long.
There may be two or possibly three separate stocks of fin
whales in the western North Atlantic, one more northern
cold-adapted stock and another more southern stock. The
ranges of the two stocks appear to overlap, such that the
winter range of the northern stock probably becomes the
spring and summer range of the more southern stock. The
third stock may consist of an isolated population in the
northern Gulf of Mexico.
Stranded Specimens
Stranded fin whales may be most readily identified by 1)
the yellowish-white coloration of the right front baleen and
the right white lower lip; 2) the numerous baleen plates
(262-473 in number); 3) the numerous ventral grooves (56-100
in number) extending to the navel and beyond (Table 2); and
4) the broad, flat sharply pointed head with only a single head
ridge.
Figure 15.—The heads of fin whales surfacing to breathe off Japan and in the northern North Atlantic (inset). When they can be approached from the right
side, fin whales can be positively distinguished from the other large balaenopterine species by the white coloration of the right lower lip and the flat, narrow
head. Note also the single central head ridge. (Photos by Japanese Whales Research Institute, courtesy of H. Omura, and K. C. Balcomb [inset].)
Figure 16.—A small group of fin whales off British Columbia. Fin whales may be found in groups of up to six or seven individuals and these groups may
congregate in feeding grounds. (Photo by G. C. Pike, courtesy of I. MacAskie.)
Figure 17.—The back of a harpooned fin whale in the eastern North Pacific (left) and in the North Atlantic (right). In both note the light grayish-white
chevrons just behind the head. These chevrons are not usually very distinctive in North Atlantic fin whales. In the animal in the left photo note also the
prominent ridge along the back behind the dorsal fin—a characteristic which prompted the common name "razorback." (Photos courtesy of Los
Angeles Examiner [left] and K. C. Balcomb [right].)
Figure 18.—Surfacing fin whales show the head and blow, then the wheellike silhouette of the back, and then the dorsal fin. Note that in this species the
dorsal fin is smaller and located farther back than that of the sei whale and appears on the surface later after the animal's blow. (Photo from the northern
North Atlantic by K. C. Balcomb.)
Figure 19.—As they begin a long dive, fin whales frequently arch the tail
stock high into the air, exposing the dorsal fin. Even on a long dive,
however, this species is not known to throw its tail flukes high into the
air or even to raise them slightly, as blue whales sometimes do when
beginning a long dive. (Photo from off Virginia by J. G. Mead.)
Figure 20.—Probably a fin whale (perhaps a
Bryde's whale) breaching in the eastern tropical
Pacific. This type of behavior has been described
for humpback, minke, and fin whales but is far more
common for the first two species. Breaching fin
whales often reenter the water with a resounding
splash, much like humpback whales, but sometimes
smoothly, head first, as minkes sometimes
do. (Photo by K. D. Sexton, courtesy of National
Marine Fisheries Service.)
Figure 21.—A head-on view of a fin whale stranded
at Ormond Beach, Fla. Note the flat narrow
appearance of the head and the single, central head
ridge. (Photo by F. Essapian, courtesy of Marineland
of Florida.)
Figure 22.—In this partly flensed fin whale, at Blanford, Nova Scotia, note the white lower lip and the white baleen in the right front. [See larger main image.] The inset photo shows
the right upper jaw of a fin whale with the baleen intact. (Photos by H. E. Winn, and from the North Pacific by Japanese Whales Research Institute,
courtesy of H. Omura [inset].)
Figure 23.—A fin whale on the ramp of the whaling station also at Blanford, Nova Scotia. Note the ventral grooves, 56 to 100 and extending at
least to the navel. (Photo by L. Rigley.)
Other Common Names
Pollack whale, sardine whale, Rudolphi's rorqual.
Description
Sei (pronounced "say") whales have been reported to
reach 62 feet (19 m).
The snout is less acutely pointed than that of the fin whale
but when viewed from the side appears slightly arched. In
general, the head is intermediate in shape between that of the
blue whale and that of the fin whale. The dorsal fin, which is
from 10 to 24 inches (25.4 to 61 cm) tall and strongly falcate in
adult animals, is located about two-thirds of the way back on
the back, farther forward than that of the blue or fin whales.
Sei whales are dark steel gray on the back and sides, and on
the posterior portion of the ventral surface. The body often
has a galvanized appearance due to scars possibly resulting
from lamprey bites inflicted during migrations into warmer
waters. These scars may be dark gray to almost white in
color. On the belly there is a region of grayish white that is
confined to the area of the ventral grooves. Neither the
flippers nor the tail flukes are white underneath. The right
lower lip and the mouth cavity, unlike those of the fin whale,
are uniformly gray. The baleen plates are uniformly grayish
black with fine grayish-white fringes. (A small number of sei
whales have been noted to have a few half-white plates near
the front of the mouth, a feature which might result in their
confusion with fin whales.)
Natural History Notes
The blow of sei whales is an inverted cone rarely taller
than 15 feet (4.6 m).
Sei whales are generally skimmer feeders and do not
usually dive very deeply. For that reason they usually surface
at a shallower angle than fin whales. The head rarely
emerges at a steep angle (except when the whales are
chased). Instead, the blowholes and a major portion of the
back, including the dorsal fin, become visible almost
simultaneously and remain visible for relatively long periods
of time. In this species it can be generally stated that the
amount of the back in the area of the dorsal fin which is
exposed above the surface as the animal sounds is
approximately the same height as the dorsal fin. When they
begin another dive, sei whales do not arch the tail stock or
flukes high. Instead, they normally submerge by slipping
quietly below the surface, often remaining in view only a few
feet down and leaving a series of tracks or swirls on the
surface as they move their tail flukes. When they are feeding
in this manner, sei whales may exhibit a highly regular
blowing and diving pattern over long periods of time.
Sei whales usually travel in groups of from two to five
individuals, though they may concentrate in large numbers
on the feeding grounds.
In the northern portion of their range, sei whales feed on
copepods. Throughout the remainder of the range, however,
their food is more varied and also includes krill and a variety
of small schooling fishes. The species derived its common
name, in fact, from its frequent occurrence with or near sei
fish.
May Be Confused With
The sei whale's smaller size and decidedly taller, more
falcate dorsal fin located well more than one-third forward
from the tail should prevent confusion with the blue whale. At
a distance, however, sei whales are difficult to distinguish
from either fin whales or Bryde's whales. The primary clues
for distinguishing them from fins are the differences in
swimming, blowing, and diving characteristics tabularized in
detail on p. 26 and the asymmetrical coloration of the fin
whale.
Sei whales may be distinguished from Bryde's whales only
upon close examination. The dorsal fin of Bryde's whales is
small, to 18 inches (45.7 cm), sharply pointed, and often worn
on the rear margin. If close examination is possible, the sei
whale will be seen to have only a single head ridge. Bryde's
whales have two additional ridges—one on each side of the
main ridge. Bryde's whales are primarily fish feeders and
their diving behavior more closely resembles that of a fin
whale than that of a sei whale. (See p. 37).
Distribution
The distribution and migrations of the sei whale during
most of the year are rather poorly known. The species is
known to avoid the colder regions near the pack ice and to
range from Iceland south to the northeast Venezuelan coast
and the northeast and southwest Gulf of Mexico. There are
also records from Cuba and the Virgin Islands. Along the
northeast United States and eastern Canadian coasts, where
most research on sei whales has been conducted, the species
migrates from New England through the Blanford, Nova
Scotia area in June and July, is found in small numbers off
eastern Newfoundland in August and September (abundant
in Placentia Bay, Newfoundland in August), and continues
northward to the Davis Straits in September and October.
An offshore stock may be found year-round in the Labrador
Sea. The summer range (May to September or October)
extends from New England to southern Arctic waters.
Though some individuals remain behind through November,
the southward movement of the bulk of the population
presumably begins in October. In general, sei whales do not
venture as far north as fin whales but may have a greater
tendency to enter tropical waters.
Stranded Specimens
Stranded sei whales are most likely to be confused with fin
whales or Bryde's whales. The three head ridges of the
Bryde's whale (sei whales have only one) assist in distinguishing
sei whales from Bryde's whales. They may be distinguished
from fin whales and all other rorquals by the following
characteristics: 1) The color of the baleen plates—uniformly
ash black with a blue tinge and fine white bristles
(Table 2). 2) The density of bristles on the plates—sei whales
have from 35 to 60 baleen fringes per centimeter; all other
rorquals have far fewer (less than 35). 3) The relative lengths
of the ventral grooves—the grooves of sei whales end well
before the navel; those of blue, fin, and Bryde's whales
extend at least to the navel. 4) The relatively small numbers
of ventral grooves (38-56)—both blue and fin whales have
more; Bryde's whales have approximately the same number.
If the animal is not in an advanced state of decomposition,
the region of white coloration of the belly may also be visible.
Figure 24.—The head of a sei whale is intermediate in shape between that of the blue whale and that of the fin whale. When
viewed from the side it is slightly arched. Note the single central head ridge, from just in front of the blowholes to near the tip of
the snout. Bryde's whales, with which sei whales are most likely to be confused in the tropical and subtropical portions of their
range, have two auxiliary ridges, one on each side of the top of the head, in addition to this main central ridge. (Photo from the
North Pacific by Japanese Whales Research Institute, courtesy of H. Omura.)
Figure 25.—Sei whales are dark gray on the right lower lip. They can be distinguished from fin whales,
which have a white right lower lip, by approaching them from the right side. (Photo from the North
Pacific by Japanese Whales Research Institute, courtesy of H. Omura.)
Figure 26.—Three views of swimming sei whales. In all three, note the tall, distinctly falcate dorsal fin (which has been described as sickle or scimitar in shape) positioned farther forward on the back
than the fins of either the fin whale or the blue whale. In the photo in the middle, note that the dorsal fin has appeared on the surface while the blowholes are still open. Sei whales, generally skimmer
feeders and rather shallow divers, often show the dorsal fin and much of the back for relatively long periods as they surface to breathe. (Photos from off central California, courtesy of National Marine
Fisheries Service [middle]; northeast of Hawaii by S. Ohsumi [left inset]; and from off Japan by Japanese Whales Research Institute, courtesy of H. Omura [right inset].)
Figure 27.—A freshly dead sei whale from the Pacific (top) and a stranded specimen in an advanced stage of decomposition at Cape Island, S.C. (bottom
and inset). Note that even though the distinctive coloration of the fresh specimen has faded on the rotting specimen, the numbers and lengths of the
ventral grooves (38 to 56 in number and stopping well short of the navel) still permit the specimen to be distinguished from fin, blue, and Bryde's whales,
in all of which the grooves extend at least to the navel. (Photos by Japanese Whales Research Institute, courtesy of H. Omura [top]; and J. G.
Mead [bottom and inset].)
Figure 28.—Dorsal view of a sei whale on the deck of a whaling
ship in the North Pacific. Note the numerous scars on the body and
the otherwise dark gray coloration of the back. (Photo by
Japanese Whales Research Institute, courtesy of H. Omura.)
Figure 29.—The right upper jaw of the sei whale stranded at Cape
Island, S.C. The baleen plates, here partly buried in the sand,
numbering from 318 to 340 per side and uniform dark gray with
fine lighter gray bristles, continue to serve as identifying
characteristics even on a badly decomposed specimen. (Photo by
J. G. Mead.)
Other Common Names
None known.
Description
Bryde's whales reach a maximum length of approximately
46 feet (14 m). They closely resemble sei whales in external
appearance. At a distance, the head of this species is similar
in profile and general appearance to that of the sei whale. The
most distinctive field characteristic of the species, however,
is the presence of three ridges along the head anterior to the
blowhole. In addition to the medial ridge characteristic of all
the other balaenopterid species, Bryde's whales have two
secondary ridges on the top of the head—one along each side
even with the blowhole running forward towards the tip of
the snout. If they can be examined at close range, Bryde's
whales can be positively identified by this character alone.
The dorsal fin of Bryde's whales is up to 18 inches (45.7 cm)
tall, extremely falcate, pointed on the tip, located well more
than one-third forward from the tail, and is often irregularly
notched or frayed on the rear margin from unknown causes.
Bryde's whales are dark gray overall, though some
individuals, like some minke whales, have a small region of
gray on each side just forward of the dorsal fin.
Natural History Notes
Bryde's whales, like minke whales, reportedly often
approach close to vessels as if curious about them. During this
time they may be examined carefully and their identifying
characteristics seen.
Though euphausiids may be an important food for this
species in limited areas, Bryde's whales often feed on
schooling fish (including pilchards, anchovies, herring, and
mackerel). This food preference is reflected in the diving
behavior of the species. Bryde's whales are not "skimmer"
feeders; they are deeper divers. When they surface to
breathe, they often rise more steeply to the surface, exposing
much of the head, roll the body sharply, and hump up the tail
stock before beginning another dive. In this species, as in the
fin whale, it can be generally stated that the amount of the
back which is exposed above the surface as the animal sounds
is approximately twice the height of the dorsal fin. They
apparently do not raise the tail flukes when beginning a dive.
May Be Confused With
At sea Bryde's whales may be confused with sei whales,
fin whales, and perhaps minke whales.
They may be most readily distinguished from sei whales
by the characteristics discussed on p. 32 and by differences in
diving behavior. The shallow-feeding sei whales surface and
blow at regular intervals over long periods of time. Bryde's
whales are deeper divers, less likely to surface, and blow at
evenly spaced intervals. If they are seen only briefly or at a
distance, however, the two species may be impossible to
differentiate.
During the winter months, when fin whales may venture
into tropical waters, they may also be confused with Bryde's
whales. But fin whales seldom exhibit curiosity about boats.
In addition, the dorsal fin of the fin whale is larger, is located
farther back on the back than that of Bryde's whale, and does
not become visible as soon after the blow. It is also less likely
to be worn on the rear margin than that of a Bryde's whale.
The head of the fin whale is more acutely pointed.
Furthermore, the right lower lip and the right front baleen of
the fin whale are white. The baleen and the right lower lip of
Bryde's whales are dark gray. If the animals can be
approached closely from the right side, positive identification
is possible using these differences in color.
Like Bryde's whales, minke whales often approach close
to vessels. But minke whales have an acutely pointed snout, a
single head ridge, and a white band on each flipper. Further,
minke whales rarely reach 30 feet (9.1 m) in maximum length.
Distribution
The distribution of Bryde's whales is rather poorly
known, no doubt in part, because the species is difficult to
positively identify at sea, and records of its occurrence may
have often been confused with those of sei whales, fin whales,
or minke whales. From stranded animals and confirmed
sightings at sea, the species appears to be found primarily
near shore in areas of high productivity in tropical or
subtropical waters, though it ventures into warmer
temperate waters as well. It has been reported from Virginia
south into the northeast Gulf of Mexico and the southeast
Caribbean, and southern West Indies (Curacao and Granada).
To date no migration has been described for the species.
Stranded Specimens
Stranded Bryde's whales can be positively identified by
the three ridges along the top of the head from the area of the
blowhole to the tip of the snout. All other species of
balaenopterid whales, except humpback whales have but a
single ridge. If the head of a stranded specimen is buried in
sand, is decomposed beyond recognition, or is otherwise
inaccessible for identification, Bryde's whales can still be
distinguished from sei whales by differences in the relative
lengths of the ventral grooves (Table 2) and from both the fin
whale and the sei whale by differences in the characteristics
of the baleen plates (Table 2).
Figure 30.—On the head of this Bryde's whale off La Jolla, Calif. two of the three head ridges characteristic of the species, the main ridge and the left
auxiliary ridge, are clearly visible. These ridges permit this animal to be positively identified as a Bryde's whale. (Photo by F. Morejohn.)
Figure 31.—Bryde's whales in the Gulf of California and north of Hawaii (inset). In both, note the tall, sickle-shaped appearance of the dorsal fin, much like
that of the sei whale. In the animal in the larger photo note the ragged rear margin of the dorsal fin, a frequently observed characteristic in Bryde's whales.
In the animal on the left note also the region of gray on the sides in front of the dorsal fin. (Photos by W. C. Cummings and S. Ohsumi [inset].)
Figure 32.—Stranded Bryde's whales at Walnut Point, Va. (top) and Panacea, Fla., Gulf of Mexico (bottom). In both animals note the head shape similar to
that of the sei whale, and the three distinct head ridges. In the animal on the bottom, note that the two outermost ridges have their origin in grooves beside
the blowholes. In the animal on the top, note also the baleen plates, up to at least 300 per side and dark gray with coarse gray bristles. There is infrequently a
rather wide interval at the front of the mouth between the left and right rows of baleen. (Photos by U.S. National Museum, courtesy of J. G. Mead [top]
and M. B. Rank, courtesy of Wide World Photos [bottom].)
Other Common Names
Humpbacked whale, bunch, hump whale, or hunchbacked
whale.
Description
Humpback whales reach a length of 53 feet (16.2 m).
The body is robust, narrowing rapidly on the tail stock.
The head is quite broad and rounded, somewhat like that of
the blue whale. The head ridge characteristic of other
balaenopterid species is indistinct and is replaced in
prominence by a string of fleshy "knobs" or protuberances,
many more of which are randomly distributed on the top of
the head and on the lower jaw. There is a distinctive rounded
projection near the tip of the lower jaw. Humpback whales
carry many barnacles and whale lice. The baleen plates are all
black with black or olive-black bristles.
The flippers are very long (nearly a third as long as the
body), are scalloped on at least the leading edge, and are
nearly all white.
The dorsal fin, located slightly more than two-thirds of the
way back on the back in approximately the same position as
that of the fin whale, is small and varies in size and shape from
a small, triangular nubbin to a more substantial, sharply
falcate fin. The dorsal fin frequently includes a step or hump,
which is quite distinct when the animal arches its back to
begin a dive and from which the species derives its common
name.
Humpback whales are basically black in color with a white
region of varying size on the belly, which upon close
examination may often be seen to be crosshatched with thin
dark lines; the flippers and the undersides of the flukes also
are white.
Natural History Notes
The blow of humpback whales is from 8 to 10 feet (2.4 to
3.1 m) tall and has been described as balloon-shaped. It is
wide relative to its height. Feeding humpback whales
habitually blow 4-8 times at intervals of 15-30 s after a long
dive. In the tropics they habitually blow 2-4 times in
succession when beginning a long dive. In diving, humpback
whales throw the tail flukes high into the air, exposing the
sometimes white undersurface and the rippled rear margin.
Humpback whales often leap clear of the water, raise a
flipper, and slap it against the water, or "lobtail," raising the
tail high into the air and bringing it crashing back to the water
in a loud report. Often, particularly when they are
encountered on their tropical breeding grounds, humpback
whales will be found lying on their sides with a long flipper in
the air.
Humpback whales feed on krill and schooling fish.
May Be Confused With
From a distance humpback whales may be confused with
any of the other large balaenopterid (rorqual) whales—blue,
fin, sei, or Bryde's. Although it is highly variable, the dorsal
fin most closely resembles that of the blue whale. However, it
is located farther forward on the back. Humpback whales
distinguish themselves from the remainder of the rorquals by
their habit of raising the flukes high into the air when starting
a long dive. (In very shallow water they may not raise the
flukes at all.) The only other rorqual to do so—the blue
whale—raises the flukes slightly or not at all.
Under some conditions humpback whales may be
confused with sperm whales at a distance. When arching the
back to begin a dive, both may show a distinct hump. Both
species frequently raise their flukes nearly vertically when
beginning a long dive but differ in several ways. The flukes of
humpback whales show varying amounts of white beneath,
are pointed on the tips, and are distinctly concaved and
irregularly rippled on the rear margin. Those of sperm
whales are all dark and more flattened and even along the
rear margin. Further the species can be distinguished in the
following ways:
| Humpback Whale |
Sperm Whale |
|---|
| BLOW |
| Projects upwards from center
of head. Usually blows
4-8 times (2-4 times in
tropics) before diving. |
Projects obliquely forward
from left side of snout.
Usually blows many times
(20-50 or more) before diving. |
| HEAD |
| Raised area around blowholes,
knobs on upper surface. |
Blunted, long, smooth. |
| FLUKES |
| Often white underneath,
concaved and scalloped on
rear margin, deeply notched. |
Smooth, all black on rear
margin. |
| FLIPPERS |
| Extremely long (to one-third
of body), white and scalloped
on leading edge. |
Short; all black. |
| DORSAL FIN (OR HUMP) |
| Triangular to falcate fin,
including a step or hump in
front of the dorsal fin;
smooth. |
Rounded hump, two-thirds
back on back followed by
knuckles or crenulations. |
When they can be examined at close range, humpback
whales can be easily distinguished from all other large whale
species with a dorsal fin by the tuberosities or knobs on the
head, by the long white flippers scalloped on the leading edge,
by the small distinctive dorsal fin, and by their distinctive tail
flukes.
Distribution
In the western North Atlantic, humpback whales are
widely distributed from north of Iceland, Disko Bay and west
of Greenland, south to Venezuela and around the tropical
islands of the West Indies. They have been reported from the
central and eastern Gulf of Mexico. Summer ranges extend at
least from New England north to the pack ice, and feeding
concentrations may be found in any portion of this region.
During winter, humpback whales migrate southward to the
shallow borderlands of Bermuda, to the Bahamas, and to the
West Indies to calve and mate.
Stranded Specimens
The most distinctive features of stranded humpback
whales are 1) the ventral grooves, 14-22 in number, very wide
and extending to the navel; 2) the tuberosities of the snout
and lower jaw, often the sites of numerous barnacle colonies;
3) the long flippers (to nearly a third of the total body length);
and 4) the distinctive rounded projection near the tip of the
lower jaw.
If these characteristics are not sufficiently clear, the
species may be identifiable by the characteristics of the
baleen plates (Table 2).
Figure 33.—Three views of blowing humpback whales. The blow of this species is usually less than 10 feet (3.1 m) tall, wider than it is high, and has been
described as balloon-shaped. In the photo on the top, the wind has already begun to distort the blow. In the photo on the bottom, two separate columns are
visible. All baleen whales have a bipartite blowhole, and if an observer is directly behind or in front of either the right whale or the humpback whale under
ideal wind conditions, the blows of these two species may appear as two distinct spouts. (Photos from West Indies by H. E. Winn [top and middle] and
from off St. Augustine, Fla. by D. K. Caldwell [bottom].)
Figure 34.—Head views of surfacing humpback whales. Note the rather broad
rounded appearance of the top of the head and the small head ridge, which extends
from just in front of the blowholes to near the tip of the snout. In humpback whales
the single central head ridge characteristic of most balaenopterid species is replaced
in prominence by a series of knobs, some of which are oriented along the same line as
the head ridge. On the animal in the inset photo note also the characteristic rounded
projection below the tip of the lower jaw, heavily encrusted with barnacles. (Photos
from off St Augustine, Fla. by D. K. Caldwell and from West Indies by H. E. Winn
[inset].)
Figure 35.—A mother humpback whale with her newborn calf off the northern West Indies. Newborn humpback whales are from 12 to 15 feet (3.7 to 4.6 m)
long and are colored like the adults. Note the mother's long white pectoral flipper, clearly visible below the surface. (Photo by H. E. Winn.)
Figure 36.—Humpback whales fall back into the water after breaching. Note the long flippers, distinctly scalloped on the leading edge. In the
animal on the top, note also the knobs on the head, visible in profile, the cluster of barnacles located on the rounded projection below the tip of the lower
jaw, and the throat grooves. (Photos off Baja California by K. C. Balcomb [top] and off Bermuda by C. Levenson [bottom].)
Figure 37.—Often, particularly on their tropical breeding grounds, humpback whales lie on their sides at the surface, the long white pectoral flipper in the
air. Note the pronounced scalloping on the leading edge. (Photos near West Indies by C. McCann [top] and H. E. Winn [bottom].)
Figure 38.—A series showing the extreme variability in dorsal fin shapes of humpback whales: (a) a small ridge, (b) slightly falcate, (c) triangular with a
pronounced hump, (d) slightly rounded, (e) distinctly rounded, and (f) taller and more distinctly falcate. (Photos from northern West Indies by H.
E. Winn [a, c, e] and C. McCann [b]; off Baja California by K. C. Balcomb [d]; and off St. Augustine, Fla. by D. K. Caldwell [f].)
Figure 39.—The humpback whale is the only large whale species with a distinct dorsal fin which regularly raises its tail flukes when beginning a long dive.
When it does so, the scalloped trailing edge is often visible (f, g, h). When the diving whale is seen from the rear, the varying degree of white coloration on
the undersides of the flukes aids in identification (h). (Photos from northern North Atlantic by K. C. Balcomb [a-f], from West Indies by C. McCann
[g], and from off Massachusetts by W. A. Watkins [h].)
Figure 40.—Detail of the head of a humpback whale harpooned off Japan. Note the knobs along the top of the head and on the lower jaw, the rounded
projection near the tip of the lower jaw and the wide ventral grooves. The large mass of tissue to the left of the animal is its tongue. In the inset photo from a
Canadian whaling station, note the baleen plates, less than 3 feet (0.9 m) long and dark olive green to black in color. (Photos by Japanese Whales Research
Institute, courtesy of H. Omura; and J. G. Mead [inset].)
Figure 41.—A humpback whale on the deck of a whaling station in western Canada. All of the species' most distinctive characteristics are evident in this
photograph: (1) the hump and the dorsal fin; (2) the knobs on the top of the snout; and (3) the long flipper, with numerous barnacles attached to its
leading edge. (Photo by G. C. Pike, courtesy of I. MacAskie.)
Figure 42.—North Atlantic humpback whales have from 14 to 20 broad, widely spaced ventral grooves which extend about to the navel. Those grooves
remain good diagnostic characters for considerable periods after the animal's death, as evidenced in the freshly killed specimen from Newfoundland (top)
and the badly decomposed stranded animal from New Jersey (bottom). (Photos from U.S. National Museum, courtesy of J. G. Mead.)
Other Common Names
Greenland whale, Arctic right whale, great polar whale.
Description
Bowhead whales, so-called because of the high-arching
jaws and the resultant contour of the head, reach a maximum
length of about 65 feet (19.8 m). They are extremely robust in
form.
When viewed from the side, some swimming bowhead
whales show two characteristic curves to the back: the first
extends from the tip of the snout to just behind the blowholes;
the second, encompassing the entire back, begins just behind
the head and extends all the way to the tail. This character
may be present only in adult animals and may be more
pronounced in males. Younger animals, particularly females,
are often stubbier and somewhat barrel-shaped behind the
head. In all animals the back is smooth, lacking even a trace of
a dorsal fin.
The head of the bowhead whale is smooth, black, and
without the bonnet and the "rock-garden," the colorful
clusters of callosities characteristic of the black right whale.
The blowholes are widely separated, and the blow emanating
from them projects upward as two separate, distinct spouts.
Though two separate columns sometimes may be visible
under windless conditions in the blows of most mysticetes,
this feature is exaggerated and is most characteristic in the
bowhead and right whales.
Bowhead whales are black overall, except for a white
"vest" of uneven coloration on the chin. Within that vest, near
the sides of the white zone, there may be a series of grayish
black to black spots, which on some animals have been likened
to a string of beads. The vest is clearly visible when a
surfacing animal is viewed from the front or the side or when
the animals hang vertically in the water with the head on the
surface and the tail flukes down, as they do during periods of
early spring mating.
Natural History Notes
Bowhead whales are usually found singly or in groups of
up to three animals, though fall concentrations may include
up to 50 animals.
Bowhead whales sometimes breach, throwing most of the
body clear of the surface and reentering with a resounding
splash.
May Be Confused With
Bowhead whales are the only species of large whales
found routinely in Arctic waters. Though other species,
including some of the balaenopterid whales and the right
whale, may venture north as far as the southern limits of the
bowhead whale and beyond, they usually do so in the spring
and summer, at a time when the bowhead whales are farther
to the north. Even if they are encountered together, bowhead
whales can be distinguished from all the balaenopterid whales
by the absence of a dorsal fin. Bowhead whales have neither a
fin nor the slightest trace of a dorsal fin or ridge, while all the
balaenopterids have a dorsal fin; and their back is extremely
smooth, like that of the right whale. The bowhead and right
whales may be readily distinguished from one another by the
characters listed below for stranded specimens.
Distribution
Though bowhead whales in the western North Atlantic
were once distributed from Arctic waters, from the edge of
the ice, south as far as the Strait of Belle Isle and the St.
Lawrence River in such abundance that they were once
referred to simply as "the whale," overwhaling through the
19th century until as recently as 1911 has severely reduced
their numbers and restricted their modern range. Today in
addition to the more abundant populations of the Bering,
Beaufort, and Chukchi seas and the Sea of Okhotsk, there are
populations off eastern Greenland and in Davis Straits, Baffin
Bay, James Bay, and the adjacent waters. Within these
ranges, bowhead whales move southward in front of the
advancing ice floes and may be expected near the southern
limits of their range from September or October through the
early spring months. Populations in the western North
Atlantic appear to be increasing slowly.
Stranded Specimens
In addition to the fact that their ranges may overlap only
slightly if at all, bowhead whales may be distinguished from
the other right whales of the western North Atlantic by
differences in 1) primary distribution, 2) coloration, 3)
lengths of the longest baleen plates, and 4) presence of
callosities.
| Bowhead Whale |
Right Whale |
| DISTRIBUTION |
| Arctic distribution south to
Davis Straits only during
winter. |
Texas, southwest Florida
north to Iceland, reaching
northern limits only during
spring and summer. |
| COLORATION |
| Black with white "vest" on
front part of lower jaw,
sometimes containing a
string of black spots; upper
jaw lacks the "rock garden." |
Sometimes black often
brown or mottled with regions
of white on chin and
belly; patches of yellowish to
pink callosities and lice
encrusting the snout in what
has been called a "rock
garden." |
| BALEEN PLATES |
| 325-360 per side; plates to 14
inches (35.6 cm) at base and
longest plates up to 14 feet
(4.3 m) long. Dark gray or
black with gray fringes;
anterior margin of some
plates whitish, showing
green iridescence in sunlight. |
250-390 per side 12
inches (30.5 cm) at base and
up to 7.2 feet (2.2 m) long.
Dirty gray with black fringes;
some anterior plates
partly or completely white. |
| BONNET AND OTHER CALLOSITIES |
| Not present. |
Present. |
Figure 43.—Swimming adult bowhead whales, particularly males, often
show two characteristic humps or curves to the back—one on the head,
ending just behind the blowholes, and a larger curve from just behind the
blowholes to near the flukes; the second is accentuated when the animal
humps up to begin a dive. (Photo by J. Lentfer.)
Figure 44.—Bowhead whales have no dorsal fin. The back is smooth and black, though often irregularly spaced
white or grayish scars of unknown origin appear. (Photos by J. Lentfer.)
Figure 45.—The unusually shaped head and the broad lower jaw, colored by a broad white vest, are evident in the swimming bowhead whale (left) and in
both members of the copulating pair (right). Also evident on the animal to the far left is the "string of black beads" which is sometimes found in the white
region. (Photos by J. Lentfer.)
Figure 46.—A harpooned bowhead whale (this one from the Alaskan population). Note the high arching upper jaw of the species. Bowhead whales have
up to at least 360 plates per side, far more than the black right whale. The longest plates, located near the middle of each jaw, are reported to reach
12 feet (3.7 m), or more, in length. (Photo by D. R. Patten.)
Other Common Names
Black right whale, Biscayan right whale, Biscay whale,
Nordcaper right whale.
Description
These right whales reach a length of about 53 feet (16.2
m).
The body is rotund and completely lacking a dorsal fin or a
dorsal ridge. The upper jaw is long, narrow, and highly
arched. The lips are similarly highly arched. The top of the
head has a series of bumps or callosities, the largest one of
which is known as the "bonnet," on the upper surface in front
of the blowholes. Yellowish-brown lice and, less frequently,
barnacles grow on the callosities. The color and extent of the
callosities varies from one individual to the next.
The two blowholes are widely separated, resulting in the
projection of the blow upward as two distinct spouts. The
body is dark on the back, sometimes black, more often brown
or mottled, usually has a region of white on the chin and belly,
and sometimes has numerous small grayish-white scars of
unknown origin. The baleen plates are up to 7.2 feet (2.2 m)
long, very narrow, and variable in color from dark brownish
through dark gray to black in color. When the animals swim,
mouth agape near the surface, the baleen sometimes
appears pale yellowish gray in color.
Natural History Notes
Right whales are usually not wary of boats and may often
be approached very closely.
Like sperm and humpback whales, they usually throw
their flukes high into the air when beginning a long dive.
Right whales feed primarily on copepods.
Historically, this whale was nearly exterminated by
hunters, who took advantage of its slow speed and who knew
that its carcass floats, to harvest these animals for their great
yield of whalebone and oil. It was these characteristics which
prompted whalers to dub these animals the "right" whales to
kill (as opposed to the ones that were too fast to catch and
sank when killed).
May Be Confused With
The distinct blow of the right whales and their smooth
dark back, devoid of any traces of a dorsal fin, make it
unlikely that the species will be confused with any other large
whales except, perhaps, the bowhead whale. In the event
that the expansion of their ranges again causes these two
species to overlap in distribution, they can be distinguished
from one another by the characteristics discussed on p. 49.
If only the flukes are seen as the animal begins a dive,
right and bowhead whales may be distinguished from the
other two species of large whales exhibiting this behavior,
the sperm and the humpback, in this way: the flukes of right
and bowhead whales are broad, pointed on the tips, greatly
concave towards a deep fluke notch, and dark below:
those of the sperm whale are more nearly triangular, while
those of the humpback whale have a jagged irregular or
rippled rear margin and are sometimes variously white
below.
Distribution
Like its more northern relative, the bowhead whale, the
right whale was once the object of a widespread and
extensive whale fishery, which reduced the species to
critically low numbers.
Though the former range of right whales is not clearly
known, the species is thought to have been abundant from the
Davis Straits south at least to the Carolinas and Bermuda and
to have occurred in winter to Florida and perhaps into the
Gulf of Mexico.
Currently, right whales are known from Iceland south to
Florida. Animals move north along the eastern Florida coast
between early January and late March. During this time the
species has also been observed in the Gulf of Mexico off
southwestern Florida and Texas. Right whales pass the coast
of New England in fair numbers in spring and continue as far
north as at least Nova Scotia. Right whales are also found off
Iceland, though the migration routes to and from Iceland
waters are not known. The recent apparent increases in
numbers at the northern and southern coastal approaches in
New England and Florida, respectively, lend credibility to
the hopeful contention that the species will again recolonize
its historical range.
Stranded Specimens
Stranded right whales can be easily identified by all the
characters discussed on p. 49 and summarized in Table 2.
Figure 47.—The V-shaped blow characteristic
of right whales. Note the two distinct spouts,
bushy in appearance. (Photo off Cape Cod by
W. A. Watkins.)
Figure 48.—A right whale off the northeastern Florida coast. Note the robust body, the smooth back, completely lacking a dorsal fin, and
the narrow rostrum, bearing the characteristic yellowish callosities. Right whales, primarily mothers with calves, show up on the Florida
coast in the early spring on their slow annual migration to the north. (Photo by N. Fain, courtesy of Marineland of Florida.)
Figure 49.—Closeup views of the heads of right whales off northeastern Florida (top left
and right) and off Cape Cod, Mass. (bottom left) clearly showing the narrow upper jaw,
the bonnet, and the widely separated blowholes. In the photo on the bottom left note the
extremely long baleen plates, characteristic of bowhead and right whales. (Photos by N.
Fain, courtesy of Marineland of Florida [top left and right]; and W. A. Watkins
[bottom left].)
Figure 50.—Right whales frequently throw their tail flukes high into the
air and then slip nearly vertically beneath the surface. Note that the rear
margin of the flukes of this species, unlike that of the humpback whale, is
smooth, broad, and concaved distinctly towards a deep fluke
notch. (Photos from the northern North Atlantic by K. C. Balcomb [a-g]
and off northeastern Florida by N. Fain, courtesy of Marineland of
Florida [h].)
Figure 51.—A stranded right whale at Narragensett Bay, R.I. Note the narrow, highly arched lower jaw; the
extremely long, narrow baleen plates, reaching lengths of 6.5 feet (2.0 m), or more; and the bonnet (the
protuberance near the tip of the upper jaw). (Photo from U.S. National Museum, courtesy of J. G. Mead.)
Figure 52.—A ventral view of a harpooned female right whale at Newfoundland. Note that this species, like the bowhead, lacks the series of ventral grooves
which characterize all other baleen whales of the western North Atlantic. Note also the absence of the vest of white on the chin, a feature which is
characteristic of the bowhead whale. Some right whales, however, do have extensive regions of white on the ventral surface, including the chin. (Photo
from U.S. National Museum, courtesy of J. G. Mead.)
Other Common Names
Cachalot, Sea Wap (St. Vincent).
Description
Male sperm whales have been reported to reach a length
of 69 feet (20.9 m), though today individuals larger than 50
feet (15.2 m) are rare. Females are much smaller, rarely
exceeding 38 feet (11.6 m).
A sperm whale is among the easiest of whales to identify
at sea even when comparatively little of the animal is visible.
It has a huge head, which comprises from a fourth to a third of
the animal's total length. (The proportion is considerably
higher for males than for females.) The blunted "squarish"
snout, which may project up to 5 feet (1.5 m) beyond the tip of
the lower jaw, houses a large reservoir containing a high-quality
oil called spermaceti.
The single blowhole is located well to the left of the
midline and far forward on the head. As a consequence the
small bushy blow, usually less than 8 feet (2.4 m), emerges
forward at a sharp angle from the head and towards the left.
Under good wind conditions this feature alone may permit
positive identification of sperm whales even at considerable
distances.
Sperm whales have a distinct dorsal hump, usually
rounded in its appearance about two-thirds of the way back
from the tip of the snout. Immediately behind the hump is a
series of knuckles or crenulations along the midline. This
hump and the crenulations are clearly visible when the
animals arch the tail before beginning a dive. There is a
ventral keel, which may also be visible as animals "sound"
(dive). The flukes of sperm whales are broad and triangular in
shape, are not concaved, but are deeply notched on the rear
margin.
Sperm whales usually are dark brownish gray in color.
The body has a "corrugated" or "shriveled" appearance. The
belly and the front of the head may be grayish to off-white.
The skin around the mouth, particularly near the corners, is
white. The undersides of the flukes and flippers vary in color
through numerous shades of browns and brownish grays.
Natural History Notes
Sperm whales may dive to depths in excess of 3,270 feet
(996.7 m) for periods of an hour or more. As do most whales
upon surfacing from a deep dive, sperm whales emit a single
explosive blow and then, depending on the length of the dive,
may remain on the surface for over 10 min and blow more than
50 times before beginning the next dive. Shorter periods on
the surface and fewer blows are more common. Females may
dive and remain on the surface for shorter periods of time
than males. When beginning a deep dive, sperm whales
throw their broad triangular flukes, dark on the undersides,
high into the air.
Sperm whales may be found singly or in groups of up to 35
or 40 individuals. Older males are usually solitary except
during the breeding season. During the remainder of the year
large groups may be bachelor bulls (sexually inactive males)
or nursery schools containing females and juveniles of both
sexes. Sperm whales are seldom found in less than 600 feet
(182.9 m) of water.
Sperm whales feed primarily on squid but may occasionally
also take octopuses and a variety of fishes.
May Be Confused With
Because of their distinctive head shape and blow, sperm
whales are unlikely to be confused with any other species
when they can be closely examined. If only the back and tail
flukes are seen, however, sperm whales may somewhat
resemble humpback whales. Both species arch the back when
beginning a dive, raising the fin or hump, and both throw the
tail flukes. The most distinctive differences between the two
species are tabularized on p. 40.
At sea the head of a sperm whale may also somewhat
resemble that of an adult male northern bottlenosed whale,
but this latter species is lighter brown in color, has a distinct
beak and a prominent dorsal fin, and is rarely found south of
lat. 42°N. In addition, the blowhole of the northern
bottlenosed whale is located well back on the head and
not—as in the sperm whale—on the front.
Distribution
Sperm whales are widely distributed in oceanic areas of
the western North Atlantic. They may be encountered from
Venezuela north at least as far as the Davis Straits, though
they apparently avoid the polar ice fields. Distribution and
migrations vary between males and females. Males range
farther to the north, while females and immature males
remain between lat. 30° and 50°N. Both groups shift
northward during spring and summer and return to southern
portions of their range in the fall. Adult males arrive off the
New England coast in August. Those reaching the
Newfoundland and Labrador coasts arrive from the deep sea,
perhaps following the slope contours, in August and
September. Males are abundant as far north as southeast
Greenland and Iceland in summer. Some animals remain as
late as November, but the majority migrate south to temperate
or tropical waters in the early fall.
Historically the primary grounds in the western North
Atlantic were those in all the following areas: the Grand
Banks just southeast of the southern Grand Banks from lat.
30° to 40°N and long. 35° to 55°W, off the Carolinas, around
the Bahamas, around many of the West Indies, and in the
southwestern Caribbean.
Stranded Specimens
Stranded sperm whales should be easy to identify. The
very narrow underslung jaw contains from 18 to 25 functional
teeth, which fit into sockets in the upper jaw. The huge,
distinctly box-shaped head and the position of the single
blowhole to the left front of the head are unmistakable clues.
Figure 53.—An aerial view of 21 sperm whales, including two young calves and several large males, off Japan. Even from an aircraft, the position of the blowhole and the body
shape clearly mark these animals as sperm whales. (Photos by Suisan Koku Company, courtesy of T. Kasuya.)
Figure 54.—A side view of a sperm whale in the West Indies, showing the distinctive blow. Note that the spout projects obliquely forward from
the blowhole, which is displaced to the left front of the head. (Photo by H. E. Winn.)
Figure 55.—Note the distinctive body shape and the position of the
blowhole of these swimming sperm whales, and, in the animal on the left,
the broad tail flukes. (Photos from the North Atlantic by S. Green [left]
and from the North Pacific by S. Ohsumi [right].)
Figure 56.—A sperm whale mother and calf off Baja California, showing the distinct dorsal hump and the extremely long head. In the bottom photo, from
the West Indies, note the dorsal hump and the crenulations of bumps which follow it. Both the hump and the crenulations may be visible as the animal
arches its tail to begin a deep dive. Note also the wrinkled appearance of the body. (Photo by K. C. Balcomb [top] and H. E. Winn [bottom].)
Figure 57.—Sperm whales often show their broad tail flukes as they begin long dives, which may last over an hour and take them to depths of several
thousand feet or more. Note the smooth rear margin and the nearly triangular shape of the flukes. (Photo from off Baja California by K. C. Balcomb.)
Figure 58.—A stranded infant male sperm whale at Melbourne Beach, Fla. (top) and a male adult sperm whale on the deck of a whaling ship in the Pacific
(bottom). Note the bulging forehead, the narrow, underslung lower jaw, the white coloration around the mouth, particularly at the corners, and the
wrinkled appearance of the body. In the bottom photo note also the whitish region on the belly. (Photos by P. Winfield [top] and Japanese Whales
Research Institute, courtesy of H. Omura [bottom].)
Figure 59.—The narrow lower jaw of a sperm whale contains from 18
to 25 large functional teeth, which fit neatly into sockets in the upper
jaw. Occasionally, the upper jaw also contains some teeth. (Photo
from the North Pacific by Japanese Whales Research Institute,
courtesy of H. Omura.)
Figure 60.—The throat and lower jaw of a sperm whale on the deck of an
eastern Canadian whaling station, showing the numerous short throat
grooves, which are most clearly evident on adult animals. (Photo by J.
G. Mead.)
Figure 61.—Detail of the broad, paddle-shaped flipper of a sperm whale
from the North Pacific. (Photo from Japanese Whales Research Institute,
courtesy of H. Omura.)
Other Common Names
Little piked whale, lesser rorqual, little firmer, sharp-headed
finner, grampus (Newfoundland), gibord (Quebec).
Description
Minke whales are the smallest baleen whale species in the
northern hemisphere, reaching maximum lengths of just over
30 feet (9.1 m). One of the most distinctive features of this
species is an extremely narrow, pointed, distinctly triangular
rostrum with a single head ridge, similar to but much sharper
than that of the fin whale (hence the common name
"sharp-headed finner"). Minke whales have a tall, falcate
dorsal fin located in the latter third of the back, in about the
same position as that of the sei whale, which often becomes
visible simultaneously with the low, usually inconspicuous
blow.
Minke whales are black to dark gray on the back and white
on the belly and on the underside of the flippers. Portions of
the underside of the flukes may be steel bluish gray. They
have a diagonal band of white on each flipper, the extent and
orientation of which varies individually.
Like the fin whale, minke whales (at least from the Pacific)
sometimes have a chevron on the back behind the head and
often have two regions of lightish-gray coloration on each
side—one just above and behind the flippers; another just in
front of and below the dorsal fin. These patches may be quite
conspicuous on some animals, indetectable on others. These
markings may also be present on Atlantic specimens, though
they have not yet been documented. The baleen, which may
be visible from close range when the animal is feeding, is
mostly yellowish white with fine white bristles. The posterior
plates (up to half) may be brown to black.
Natural History Notes
Minke whales are frequently found as single animals,
pairs, or trios, though they may congregate in areas of food
concentration in the northern seas during the spring and
summer. They are more likely to be seen up close than their
larger cousins—the blue, fin, and sei whales—because they
often closely approach boats, particularly stationary boats, as
if curious about them.
Minke whales may also approach very close to shore and
often enter bays, inlets, and estuaries.
Like fin whales, they often arch the tail stock high into the
air when beginning a long dive. However, they do not raise
the flukes above the surface when beginning a dive.
Minke whales feed primarily on small shoal fish (herring,
cod, pollack, and capelin).
Minkes sometimes breach, leaping completely clear of the
water and entering smoothly, head first, or with a substantial
splash like humpback whales.
May Be Confused With
When they are seen at relatively close range, minke
whales can be readily distinguished from the other rorquals
that have relatively tall, falcate dorsal fins (fin, sei, and
Bryde's whales) by their considerably smaller size and by
their distinctive white band on each flipper.
At a distance, however, positive identification may be
difficult. Minke whales have a small, low, inconspicuous blow.
Like sei whales, they frequently expose the dorsal fin
simultaneously with the blow, but minke whales hump the
tail stock much higher when beginning a long dive—more like
fin whales.
From a distance, minke whales might also be mistaken for
northern bottlenosed whales (or any of several other beaked
whales with a similar dorsal fin). They can be distinguished
by the differences in head shape, body color and markings,
and behavior, detailed on p. 67.
Distribution
Minke whales are distributed in the polar, temperate, and
tropical waters of the western North Atlantic. They are
found from the pack ice south to at least Anguilla, Lesser
Antilles, and the eastern Gulf of Mexico, though they appear
to be most abundant in temperate waters north of the latitude
of New York and are infrequently reported from tropical
waters. At least some of the population migrates to the
northern portions of their range in spring and back south in
autumn. They often approach close to shore and enter river
mouths, inlets, and estuaries.
Minke whales arrive along the Canadian coast in May or
June. Some migrate as far north as Hudson Strait, where
they remain until the freeze in October, November, or
December. By December the majority of the population has
begun to move to the south, although some animals remain
behind so long as to become entrapped in the ice and die.
Spring and summer concentrations along the Canadian coast
correspond to concentrations of capelin, cod, and herring.
Southern concentrations, also corresponding with concentrations
of herring, extend farther offshore at least to the edges
of the Grand Bank. Minke whales also summer off the south
coast of western Greenland, which they probably reach from
waters southwest of Iceland. Minke whales also occur in
deep pelagic waters.
Stranded Specimens
Stranded minke whales can be most readily identified by:
1) their small size (to just over 30 feet [9.1 m]); 2) the
transverse white bands on the flippers; 3) the yellowish-white
baleen plates (up to half the posteriormost plates may
be brown or black), 300-325 per side in number and having
fine white bristles (the plates are up to 4.75 inches [12 cm]
wide at the base and up to 8 inches [20.3 cm] long); and 4) by
the 50-70 thin ventral grooves, ending well before the navel,
often just even with the flippers.
Figure 62.—The minke whale, at a maximum length of just over 30 feet (9.1 m), the smallest baleen
whale species of the western North Atlantic, is distributed in polar, temperate, and tropical waters.
These animals usually have a low, inconspicuous blow and are sometimes curious enough about
boats that they will alter their course to investigate them. Note the two areas of light gray on the
sides of the body, characteristic of at least Pacific minke whales. (Photo from off British Columbia,
courtesy of Nanaimo Free Press.)
Figure 63.—Three views of minke whales at sea. In all note the transverse
band of white on the flippers and the sharply pointed head. Note the gray
chevron visible on the back (top), the absence of a conspicuous blow and
the appearance of the prominent dorsal fin on the surface while the
blowholes are still exposed (middle), and the distinctive regions of light
gray on the sides (bottom). (Photos from off San Diego, Calif. by G. E.
Lingle [top]; from the northern West Indies by H. E. Winn [middle]; and
from the western Pacific by Japanese Whales Research Institute, courtesy
of H. Omura [bottom].)
Figure 64.—Minke whales are also known as sharp-headed finners. On this animal from the North Pacific,
note the sharply pointed head and the single central head ridge. (Photo by Japanese Whales Research
Institute, courtesy of H. Omura.)
Figure 65.—A minke whale stranded at Santa Barbara, Calif. Note the dark back, the white-banded flipper, and the 60-70 fine ventral grooves extending to
just behind the flippers. The short, white baleen plates are visible in the open mouth. (Photo by S. Anderson.)
Figure 66.—Minke whales have from 300 to 325 short, yellowish-white baleen plates (up to half the
anteriormost plates may be brown or black) with fine white bristles on each upper jaw. (Photo from
Santa Barbara, Calif. by S. Anderson.)
Other Common Names
None known.
Description
Northern bottlenosed whales reach a length of 32 feet (9.8
m) and are robust in form. They are characterized by a
bulbous forehead, which is more pronounced on larger
animals and most distinctive in adult males, and by the
dolphinlike beak displayed in animals of all sizes and ages,
which is sometimes visible as the animals surface steeply to
breathe.
The blowhole is located in an indented area behind the
bulbous forehead, and the blow emanating from it projects
upward or slightly forward to a height of up to 6 feet (1.8 m),
is bushy and is visible from a considerable distance under low
wind conditions. The dorsal fin, located two-thirds of the way
back on the back, reaches at least 12 inches (30.5 cm) in height
and is distinctly falcate. The dorsal fin may be visible from a
distance of several hundred meters.
Northern bottlenosed whales are usually brownish in
color, though the markings change with age. Smaller animals
are a uniform chocolate brown. Larger animals retain the
chocolate brown color on the back but are often lighter on the
sides and the belly and often have irregular patches or
blotches of grayish-white coloration on the back and sides.
Extremely large animals, presumably older males, often
have a white head. The flippers and the undersides of the
flukes are uniformly brown in color.
Natural History Notes
Northern bottlenosed whales often form tightly packed
groups of up to 10 or more animals. This species holds the
anecdotal record for the longest dives, having been reported
by early whalers to remain submerged over 2 h. They are
probably deep divers, feeding primarily on squid (though
they may take fishes as well), and they rarely go in water
shallower than 100 fathoms (183 m).
After a long dive, northern bottlenosed whales will
sometimes remain on the surface for 10 min or more, blowing
at regular intervals before making another dive. After the
last blow of a series or when the animals are startled by a
boat, they may show the tail flukes as they begin to dive. The
flukes are not notched on the rear margin.
Northern bottlenosed whales have been observed to show
curiosity about boats, coming to them from a considerable
distance. They have also been observed to "lobtail," raising
the tail flukes above the water and slapping them against the
surface, and to jump clear of the water.
In the late 19th century, after stocks of bowhead whales
were severely reduced by overwhaling, northern bottlenosed
whales became a prime target of arctic whalers. They were
sought because in addition to whale oil produced from the
body blubber, the forehead of the species yielded quantities
of spermaceti like that obtained from sperm whales.
May Be Confused With
Northern bottlenosed whales have a northerly and
deep-water distribution. Within their range, they may be
confused at a distance with minke whales, with sperm
whales, or perhaps with North Sea beaked whales.
Minke whales (p. 63) have a falcate dorsal fin located in
approximately the same position as that of the northern
bottlenosed whale. However, minke whales have a flathead in
front of their two blow holes and are black to dark gray
on the back.
Sperm whales (p. 57) have a squarish head that may
somewhat resemble that of an adult male northern
bottlenosed whale. However, there are numerous characteristics
which will permit these species to be distinguished even
from a distance:
| Northern
Bottlenosed Whale |
Sperm Whale |
| BLOW |
| Low and bushy; projects
upward from indentation on
top of head. |
Low and bushy, projects
obliquely forward from left
side of head; usually less
than 8 feet (2.4 m). |
| COLORATION |
| Lighter brown; adults splotched
with grayish white;
body smooth. |
Brownish gray; body appears
wrinkled. |
| FLUKES |
| Rarely notched; seldom raised
on long dive. |
Notched; raised on long dive. |
| HEAD |
| Tapering in younger animals;
bulbous in adults;
white in older animals; beaked. |
Squarish, long, all black;
bbeakless. |
A further aid to distinguishing northern bottlenosed
and sperm whales at sea is the fact that the
sperm whales that are found in areas where northern
bottlenosed whales are encountered are usually older,
larger males from 40 to 60 feet (12.2 to 18.3 m) long.
Northern bottlenosed whales do not exceed 32
feet (9.8 m).
Northern bottlenosed whales may also be confused with
the poorly known North Sea beaked whale (p. 82). When
they can be examined at close range, however, northern
bottlenosed whales should be distinguishable on the basis of
the distinctly bulbous forehead.
Distribution
In the western North Atlantic, northern bottlenosed
whales are restricted to Arctic and north temperate waters,
where they most commonly occur in offshore areas. They
have been reported from Davis Straits and the entrance to
Hudson Strait, the Gully southeast of Sable Island, and as far
south as Narragansett Bay, R.I.
In the spring and summer they concentrate near the
northern limits of their range, occasionally visiting deep
channels of the Gulf of St. Lawrence and eastern
Newfoundland in summer. During these seasons they may
extend to the edge of the pack ice.
In the fall and winter the bulk of the population migrates
southward. Many probably winter in the Labrador Sea while
others move farther southward and farther offshore.
Stranded Specimens
Like the beaked whales discussed on p. 70 through 83,
the northern bottlenosed whales have no notch in the tail
flukes, have two throat grooves forming a V-shape on the
chin, and have only two teeth in the lower jaw, with those
teeth emerged from the gums only in adult males. These
teeth may have sometimes fallen out of older males, but the
tooth sockets should still be visible in the gums.
NOTE: Some specimens—both male and female—will be
found to have a series of vestigial teeth the size of toothpicks
in the upper and/or lower jaws. Similar vestigial teeth, 5-40
in number, sometimes occur in goosebeaked whales (p. 70).
Further when they are prepared for museum collections, the
lower jaws of adult northern bottlenosed whales may be
found to contain a second pair of teeth just behind the first.
Northern bottlenosed whales may be distinguished from
the remainder of the beaked whale family, however, by the
extremely robust body, by the bulbous forehead, which is
more extensively developed in larger animals, particularly
males, and by the pronounced dolphinlike beak.
Figure 67.—Northern bottlenosed whales at sea off Nova Scotia. Note the prominent dorsal fin and the blotches of grayish-white coloration on the body.
Northern bottlenosed whales reach 32 feet (9.8 m) in overall length. (Photo by H. E. Winn.)
Figure 68.—Views of the heads of male northern bottlenosed whales off Nova Scotia. Note the distinctive beak (right) and the bulbous forehead, features
which develop with age and are most pronounced in adult males. In the animal on the left, note also the low bushy blow emanating from the indented area on
the top of the head. (Photos by H. E. Winn.)
Figure 69.—Northern bottlenosed whales occasionally raise their tail
flukes when beginning a dive. At close range, these flukes can often be
seen to lack a distinctive notch on the rear margin. (Photo from off Nova
Scotia by J. Hain.)
Figure 70.—A stranded northern bottlenosed whale from Holland. Note the bulbous forehead, the long dolphinlike beak and the frequent absences of a
notch in the rear margin of the tail flukes. (Photo by J. P. Strijbos, courtesy of Rijksmuseum van Natuurlijke Historie te Leiden.)
Other Common Names
Ziphius, Cuvier's beaked whale, grampus (St. Vincent)
(see also p. 96).
Description
Goosebeaked whales reach a length of 23 feet (7 m).
Females are slightly larger than males of the same age.
Calves are probably less than about 6 feet (1.8 m) at birth.
The head is small relative to the body length and, when
viewed laterally, is slightly concaved or scooped on the upper
margin. The cleft of the mouth is small, smaller than in any
other species of beaked whales. The beak is indistinct in
larger individuals. There is a distinct indentation on the back
behind the head. Two teeth are found at the tip of the lower
jaw of adult males only.
The dorsal fin is relatively tall and distinct, to at least 15
inches (38.1 cm), smoothly falcate, and located well behind
the midpoint of the back. The blowhole is located far forward
on the top of the head. The blow, which may project slightly
forward and slightly off to the left, is usually low and
inconspicuous. Though the first blow after a long dive may be
more distinct, even it is rarely visible even under good wind
conditions for more than a few hundred yards.
Descriptions of the color pattern vary. Individuals may be
dark rust brown, slate gray, or fawn colored on the back and
generally lighter on the belly. Some appear dark in both
regions, still others—particularly youngsters—appear lighter
gray or tan on the belly. The body is frequently covered
with white or cream-colored blotches (particularly on the
belly). The tail flukes are dark on the bottom. The head is
frequently paler in color. Old males have a distinct white head
and are frequently extensively scarred.
Natural History Notes
Goosebeaked whales frequently occur in groups of from 10
to as many as 25 individuals. They have been reported to
jump clear of the water. They are presumably deep divers
and are known to stay down for more than 30 min. When they
begin a deep dive, they often raise their tail flukes above the
surface and dive nearly vertically. Goosebeaked whales feed
primarily on squid.
May Be Confused With
So little is known of the external appearance and behavior
of the living beaked whales at sea that all the species may
easily be confused.
Goosebeaked whales are larger than all other beaked
whale species with the exception of the northern bottlenosed
whale. Upon close examination they may be distinguished
from the northern bottlenosed whale by the lighter coloration
of the head, reaching an extreme in the white head of adult
males. (See p. 67 and Fig. 75.)
Distribution
As with other species of beaked whales seldom
encountered or at least seldom positively identified at sea,
the distribution of goosebeaked whales is poorly known and
must be constructed from records of stranded specimens.
Such records, often involving sick individuals that may have
washed ashore from considerable distances, may give an
inaccurate picture of normal ranges.
In general, stranding reports suggest that goosebeaked
whales are sparsely but widely distributed in nonpolar
latitudes. They appear to be primarily tropical in
distribution, though they venture into temperate areas in
summer. They have been reported from Massachusetts and
Rhode Island south to Florida and thence to the islands of the
West Indies. They are frequently stranded along the Florida
coast and are not an uncommon species in the extant whale
fishery of the Antillean Islands. The fact that goosebeaked
whales strand more frequently than other beaked whales
may reflect either a greater abundance or a greater tendency
to approach close to shore.
They are probably primarily an offshore species.
Stranded Specimens
To be positively identified, stranded goosebeaked whales
in an advanced state of decomposition may require museum
preparation and examination of the skull and teeth. Fresh
specimens may be tentatively identified by the characters
illustrated in the figures.
Figure 71.—Goosebeaked whales have been rarely seen at sea. In these photos from the eastern tropical Pacific, note the white head of the animal on the
left. Goosebeaked whales are wary of boats and may dive for 30 min or more. When they surface, their blow, usually very indistinct, may project forward
and slightly to the left. (Photos by K. D. Sexton, courtesy of National Marine Fisheries Service.)
Figure 72.—A beaked whale, probably a goosebeaked whale, jumps
beside a research ship off northwestern Baja California. Note the position
and shape of the dorsal fin and the depression just behind the
head. (Photo by S. Leatherwood.)
Figure 73.—A goosebeaked whale stranded in Delaware. Goosebeaked whales are primarily tropical in distribution, though they apparently venture into
temperate areas in summer. Note the prominent dorsal fin, the lighter coloration of the head, and the depression just behind the head. (Photo from U.S.
National Museum, courtesy of J. G. Mead.)
Figure 74.—A closeup of the dorsal surface of the
flukes of a juvenile goosebeaked whale stranded in the
northeastern Gulf of Mexico. Like other members of
the beaked whale family, goosebeaked whales lack a
distinctive notch in the rear margin of the flukes.
(Photo courtesy of Florida's Gulfarium.)
Figure 75.—Stranded goosebeaked whales, an adult male from northern California (top) and an
immature female from the northeastern Gulf of Mexico (bottom). Note the brownish color of the
back, marked in the adult animal by blotches of lighter gray and numerous scratch marks,
presumably tooth rakes. Note also the mouth cleft, shorter in this species than in any other beaked
whale species, and the slightly concave appearance to the upper margin of the head. The beak is
usually less developed in large animals. The inset photo shows a ventral view of the tip of the lower
jaw of an adult male from the east coast of Florida. The two teeth of the species are emerged above
the gum only in adult males. (Photos by W. J. Houck [top], Florida's Gulfarium [middle], and W.
A. Huck, courtesy of Marineland of Florida [inset].)
Other Common Names
Grampus (St. Vincent) (see also p. 96).
Description
In addition to the northern bottlenosed whale (p. 67) and
the goosebeaked whale (p. 70), four other species of beaked
whales have been reported from the western North Atlantic.
All four species are known primarily from stranded
specimens and have been rarely encountered at sea.
Therefore statements of range are usually limited to
inferences from locations of strandings, and information on
appearance and habits of the species in the wild is almost
totally lacking.
The infrequent encounters with beaked whales at sea may
result from such factors as 1) a low inconspicuous blow, 2)
avoidance of ships, and/or 3) distribution in small groups in
offshore areas well outside the normal boating lanes.
The following descriptions will aid primarily in identifying
stranded specimens. Though subtle differences in ranges,
color patterns, and dorsal fin shapes and positions may be
helpful in narrowing the choices of living animals, the species
will continue to be extremely difficult to distinguish from one
another in the brief encounters typical at sea until additional
data are collected.
The beaked whales have the following characteristics in
common: 1) two small creases forming a V-shape on the throat,
2) the absence of a conspicuous notch on the rear margin of the
tail flukes (some specimens have a slight indentation), and 3)
the absence of functional teeth in all except adult males.
Adult males have a single pair of teeth in the lower jaw, the
position and description of which help to identify the species.
The teeth of females are not functional and only rarely
emerge from the gums. Therefore, if a stranded animal is an
adult male, its species can be determined by the position and
description of the teeth. For example, in Mesoplodon mirus,
the teeth are located near the tip of the lower jaw; in M.
europaeus, they are located about a third of the way from the
tip of the snout to the corner of the mouth; in M. bidens, they
are nearly half way from the tip of the snout to corner of the
mouth; and in M. densirostris, they are located in large
prominences near the back of the mouth.
If the animal is a female or an immature male, however,
museum preparation and examination might be required
before the species can be positively determined. The
following four sections summarize characters of western
North Atlantic beaked whales.
Figure 76.—An unidentified beaked whale from the mid-Pacific. Note the marks along the back, presumably tooth rakes, consisting of scratches that are
paired and close together. A beaked whale in the western North Atlantic marked in this manner would be a northern bottlenosed whale (p. 67), a goosebeaked
whale (p. 70), or a True's beaked whale (p. 77). These are the only three species in which the teeth are located close together near the tip of the
lower jaw. (Photo by K. C. Balcomb.)
Figure 77.—Various views of a herd of five or six unidentified beaked whales, possibly dense-beaked whales, 12 miles off Pokai Bay, Oahu, Hawaii. The
animals were very shy and had low indistinct blows, making them difficult to spot and track. As they surfaced, individuals frequently bucked their heads
and slapped the chin against the surface, rather than rolling. They did not raise their tail flukes when beginning their long dives. (Photos by E.
Shallenberger, Sea Life Park, Hawaii.)
(Because so little is known of beaked whales every encounter should be recorded in as much detail as possible.)
Figure 78.—Adult male beaked whales,
showing the body profile and the relative
positions of the teeth. Remember that the
teeth of females and immature males are
concealed beneath the gums. (Drawing by
L. Winn.)
Other Common Names
None known.
Description
True's beaked whales reach a length of at least 16 feet (4.9
m) long. They are chunky in midbody and narrow rapidly
towards the tail, closely resembling goosebeaked whales
(p. 70). In overall body shape, the head is small with a slight
indentation in the area of the blowhole, a slight bulge to the
forehead, and a pronounced beak. The flippers are small
(from one-fourteenth to one-tenth the body length). The
dorsal fin is small, slightly falcate, located in the latter third
of the back, and followed by a pronounced ridge on the tail
stock. The flukes, which sometimes contain a very slight
notch, are broad (to almost one-fifth the body length).
True's beaked whales are dull black to dark gray on the
back, lighter slate gray on the sides, and white on the belly.
The body is frequently covered with light colored spots or
splotches and bears numerous pairs of scratch marks,
presumably tooth rakes (Fig. 76).
The flippers are all black and are attached in the dark coloration
of the animal's side. The flukes are dark above and
below.
May Be Confused With
True's beaked whales are most likely to be confused with
goosebeaked whales (p. 70) but may also be confused with
any of the other beaked whales species (p. 74 and Fig. 78).
Distribution
True's beaked whales appear to be primarily temperate in
distribution. They have been reported from Cape Breton
Island, Nova Scotia south as far as Flagler Beach in Florida.
Northernmost records are for summer months.
The range of True's beaked whales overlaps with that of
the Antillean beaked whale but is more northerly.
Stranded Specimens
The teeth of adult male True's beaked whales may be
visible near the tip of the lower jaw, a characteristic shared
with the goosebeaked whale (p. 70) and the northern
bottlenosed whale (p. 67). Both these other species reach
substantially greater maximum lengths than True's beaked
whales, however, and should be readily distinguishable by
this and the number of other highly distinctive characteristics
of each species.
Females and subadult males may be confused with any of
the beaked whales species (p. 74 and Fig. 78).
Figure 79.—Two views of the body of a stranded True's beaked whale from
northeastern Florida. This species reaches at least 16 feet (4.9 m) and closely
resembles the goosebeaked whale in general body shape. It is distributed in
temperate waters from Nova Scotia to Florida. (Photos courtesy of Marineland of
Florida.)
Figure 80.—The head of a True's beaked whale stranded in North Carolina. Note
the small head, the pronounced beak, and the position of the blowhole in the
indentation behind the forehead. The teeth, visible above the gums only in adult
males, are in the position indicated by the arrow. The photo on the right shows
the two V-shaped throat grooves characteristic of beaked whales. (Photos from
U.S. National Museum, courtesy of J. G. Mead.)
Other Common Names
Gulfstream beaked whale, Gervais' beaked whale.
Description
Antillean beaked whales reach a length of at least 22 feet
(6.7 m). They are slender in form and appear somewhat
laterally compressed (i.e., taller than they are wide). The
head is extremely small and tapers rapidly to a narrow beak.
The flippers are small (to about one-twelfth the body length)
with their origin well down on the sides of the body. The
dorsal fin is small, located behind the midpoint of the back,
and variable in shape from falcate to triangular. The flukes
are less than one-fifth the body length and are not notched.
Antillean beaked whales are dark grayish black on the
back and sides, slightly lighter on the abdomen. The flukes
are dark gray above and below.
Natural History Notes
Antillean beaked whales are probably primarily oceanic in
distribution and are known to feed on squid.
May Be Confused With
Antillean beaked whales may be confused with any of the
other beaked whales though they are larger than all except
the northern bottlenosed whale (p. 67) and the goosebeaked
whale (p. 70).
Distribution
Antillean beaked whales have been reported stranded
from the latitude of Long Island, N.Y. south to Florida,
thence into the Caribbean and the Gulf of Mexico.
Stranded Specimens
The teeth of Antillean beaked whales are located at the
suture of the mandible, about one-third of the way from
the tip of the snout to the corner of the mouth (Fig.
78).
Figure 81.—Two views of an Antillean beaked whale stranded in New Jersey in 1899. Note the very small head, the prominent
back-curved dorsal fin, and the slightly concave rear margin of the tail flukes, which lack a distinct notch. (Photos by F. W.
True, courtesy of U.S. National Museum.)
Figure 82.—Two views of an Antillean beaked whale stranded in Jamaica. This
species reached at least 22 feet (6.7 m) in length. Compared to the smaller True's
beaked whale, Antillean beaked whales have a smaller head, a narrower beak, and a
taller, narrower body. Furthermore, the teeth of this species are located about
one-third of the way back from the tip of the snout to the corner of the
mouth. (Photos by J. J. Rankin.)
Other Common Names
None known.
Description
Dense-beaked whales reach a length of at least 17 feet (5.2
m). The body is distinctly spindle-shaped. The head, the
contour of which is the most distinctive characteristic of this
species, is marked by a prominent rise, located near the angle
of the gape on each side. This rise, which bears the teeth,
gives a peculiar high, arching contour to the mouth (Fig. 84),
particularly in adult males.
The flippers are small (one-eleventh to one-tenth the body
length) and have their origin in the lighter color of the lower
sides. The dorsal fin varies from small and triangular to
nearly falcate and pointed on the tip. It is located behind the
midpoint of the back. The flukes are from one-sixth to
one-fifth the body length, are seldom notched, and
occasionally even bulge slightly backwards near the center of
the rear margin.
Dense-beaked whales are black or charcoal gray on the
back, slightly lighter on the abdomen. They are somewhat
blotched with grayish white and are often extensively
scratched or scarred. The flippers are lighter than the back.
The flukes are dark above, light below.
Natural History Notes
From stomach contents of stranded animals dense-beaked
whales are known to feed on squid.
May Be Confused With
Adult male dense-beaked whales can be separated from
the other beaked whales by the high, arching contour to the
corners of the mouth. If there is no adult male in the group,
however, dense-beaked whales may be confused with any of
the other beaked whales species.
Distribution
Dense-beaked whales have been reported from Peggys
Cove, Nova Scotia south to Florida. From all accounts, this
species appears widely but sparsely distributed in warm
temperate seas.
Stranded Specimens
Adults of this species should be distinguishable by the
highly distinctive contour of the mouth. The teeth, located in
the high rise of the mouth, are oriented slightly backwards.
Figure 83.—A dense-beaked whale in the tank at New York Aquarium. Note the position of the prominent dorsal fin, just breaking the surface. The blow of
beaked whales is usually small and inconspicuous and reportedly projects markedly forward from the head. (Photo by J. G. Mead.)
Figure 84.—Views of the heads of dense-beaked whales. Females
(bottom) and immature males have a slight curvature to the rear of the
mouth. As they mature, males (middle and top) begin to display the two
arching prominences near the corners of the mouth which give the
characteristic contour to the mouth. The teeth are located in these
prominences and are oriented slightly backwards. (Photos from
northeastern Florida by W. A. Huck, courtesy of Marineland of Florida
[top and middle] and by J. G. Mead [bottom].)
Figure 85.—A dense-beaked whale stranded in northeastern Florida. This species reaches about 17 feet (5.2 m) and is black or charcoal gray on
the back, lighter gray on the sides, and frequently marked with grayish-white blotches and often extensively scarred. (Photo by W. A. Huck,
courtesy of Marineland of Florida.)
Other Common Names
Sowerby's beaked whale.
Description
North Sea beaked whales reach a length of at least 16.5
feet (5 m). The body is distinctly spindle-shaped, but
apparently more robust near midbody than that of the
dense-beaked whale. The head is characterized by a
pronounced bulge in front of the blowhole, a slightly concave
forehead, and a moderate to long beak. The flippers are
relatively long (one-eighth to one-ninth the body length). The
dorsal fin is reportedly tall and variable in shape from
triangular to slightly falcate and is located just behind the
midpoint of the back. The flukes are not notched but are
sometimes quite concave on the rear margin.
Adult North Sea beaked whales are dark charcoal gray on
the back with white spots overall. Young animals are also
dark charcoal gray on the back but are lighter on the belly and
are unspotted. The flukes of adults are dark above and below.
Those of young are dark above, lighter below.
Natural History Notes
North Sea beaked whales are known to feed on squid.
May Be Confused With
North Sea beaked whales are the most northerly species
of beaked whales. No other species is very likely to be
encountered in the same area.
Distribution
North Sea beaked whales have been reported in the
offshore waters from the latitude of New England north
perhaps to the pack ice. Individuals are occasionally drawn to
the coasts of Newfoundland in summer, presumably by
concentrations of squid, a known food item.
Stranded Specimens
The teeth of North Sea beaked whales are located about
midway between the tip of the snout and the corner of the
mouth. Except for this characteristic and their northerly
distribution, however, this species might easily be confused
with any other of the beaked whales species.
Figure 86.—North Sea beaked whales are the most northerly of the beaked whale species, extending north as far as the pack ice.
They reach at least 16.5 feet (5.0 m) and can be identified on the beach by the position of the teeth near the middle of the lower jaw.
Little is known of the species at sea. (Drawing by L. Winn.)
Figure 87.—A female North Sea beaked whale (16.5 feet [5.0 m]) stranded in Hjertuika in 1957. (Photo courtesy of A. Jonsgard.)
Other Common Names
Blackfish (see also pilot whales, p. 91 and 94), sword fish
(Canada), grampus (see p. 96), whitefish (St. Vincent),
Espladon (Quebec).
Description
Killer whales are the largest member of the dolphin
family. Adult males reach a length of at least 30 feet (9.1 m)
and are robust in form. One specimen of 31 feet (9.5 m) was
recorded for the western North Pacific. Females are
considerably smaller and less stocky. Newborn are
approximately 7-8 feet (2.1-2.4 m) long. Killer whales have
large paddle-shaped flippers.
The most distinctive field character of the species is the
dorsal fin. In adult males it is extremely erect and may be as
much as 6 feet (1.8 m) tall. Though the fin of females and
immature males is less than 3 feet (0.9 m) tall, it is
nonetheless taller even in these animals than in any other
cetacean species and is distinctly falcate and pointed on the
tip.
Killer whales are basically black with an extensive region
of white on the undersides extending from the lower jaw to
the anal region with a branch extending onto the flanks
behind the dorsal fin. There is an oval white patch on the side
of the head just above and behind the eye. In newborn and
very young calves, these regions may be tan to lemon yellow
in color. Most animals have a light-gray saddle marking just
behind the dorsal fin. The undersides of the flukes are
usually white. Both all-black and all-white animals have
been reported.
Natural History Notes
Killer whales travel in groups of from a few to 25 or 30
individuals, though herds of 150 have been reported. Males
appear polygamous, and females and young may form groups
separate from young bachelors and bulls.
Killer whales are extremely fast swimmers, capable of
reaching top speeds of 25 knots or more, and have been
reported "porpoising" and breaching. Individuals and entire
groups have also been reported "spy-hopping," or
"pitchpoling," behaviors which consist of hanging vertically
in the water with the head and much of the body (to just
behind the flippers) exposed above the surface.
Killer whales feed on squid, fishes, sea turtles, seabirds,
and marine mammals.
Controversy still continues over whether or not killer
whales pose a threat to man. Documented attacks of killer
whales on boats are rare and have usually been provoked
(i.e., harpooning or attempts to capture). Only two uncertain
instances of attacks in the wild have been reported, but all
divers and mariners should be cautioned that this powerful
animal is perfectly capable of doing tremendous damage and
should not be provoked.
May Be Confused With
Because of its very distinctive dorsal fin, body shape, and
coloration, the killer whale is not likely to be confused with
any other whale when it can be examined at close range or
when an adult male is present in the group. Pods of females
and immature animals, however, may be confused with false
killer whales or with grampus. The killer whales may be
distinguished from false killers by the following differences:
| Killer Whale |
False Killer Whale |
| BODY SHAPE |
| Chunky. |
Slender. |
| BODY COLOR |
| Black with white on belly,
flank, and head. |
All black with some gray on
belly. |
| DORSAL FIN |
| Very tall and erect in adult
males; tall and slightly back
curved in female. |
Shorter, slender, strongly
falcate. |
| HEAD SHAPE |
| Broad, rounded. |
Tapered, slender. |
| FLIPPER SHAPE |
| Paddle-shaped. |
Moderately long with
characteristic hump near
middle on forward margin. |
| LENGTH |
| To at least 30 feet (9.1 m). |
To at least 18 feet (5.5 m). |
Furthermore, false killer whales are the only "blackfish"
which are known to ride the bow wave of a ship.
Grampus have a tall dorsal fin (15 inches [38.1 cm]) which
is very similar in appearance to that of adult female and
juvenile killer whales. But grampus have much lighter
coloration, from slate gray to nearly all white, and larger
animals are covered with numerous scratches. Upon closer
examination they can be further distinguished from killer
whales by a crease in the front of the head dividing the melon
into two distinct sections. Grampus are considerably smaller,
to about 13 feet (4 m) maximum length.
Distribution
In the western North Atlantic killer whales have been
reported from the polar pack ice south to Florida and St.
Vincent, Lesser Antilles, and into the Gulf of Mexico at least
as far as Texas, though they are far more common in the
cooler waters from about New Jersey north. Throughout
their range, killer whales seem to prefer coastal areas and
often enter shallow bays, estuaries, and river mouths in
search of food.
Migrations of the species are probably closely tied to
movements of their food supply. They annually arrive on the
coast of New England with the tuna. Along the Canadian
coasts, where distribution and migrations have been
described in some detail, killer whales appear to move
inshore in spring and summer. Many arrive off the east coast
of Newfoundland in June, the Strait of Belle Isle in June and
July, and slightly later along the Labrador coast and Arctic
waters. They are found around the loose ice in April,
presumably feeding on harp seals, Pagophilus groenlandicus,
and hooded seals, Cystophora cristata, and are frequent in
the St. Lawrence estuary in spring and autumn following the
movements of the white whales. The northward movements
in spring also coincide with migrations of balaenopterine
whales, which have also been reported among the food items.
Killer whales may remain in arctic or subarctic waters until
driven out by new forming ice in October and November.
Though the migration has not been as thoroughly described,
killer whales apparently begin shifting southwards in
autumn.
Stranded Specimens
Stranded killer whales should be readily identifiable by
the robust body, the distinctive body markings, and in larger
animals the tall dorsal fin. Killer whales have from 10 to 12
large, prominent teeth on each side of the upper and lower
jaws.
Figure 88.—A small herd of killer whales off southern California (top) and details of an adult male from that herd (middle) and of females or immature
males off Islas San Benito, Baja California (bottom). Adult males have a tall erect dorsal fin, which may be more than 6 feet (1.8 m) tall, while the fins of
females and immature males are less than 3 feet (0.9 m) tall, distinctly falcate, and pointed on the tip. Both sexes frequently have a grayish-white region,
called a "saddle," behind the dorsal fin. (Photos by T. Dohl [top and middle] and S. Leatherwood [bottom].)
Figure 89.—Killer whales are often distributed very close to shore. In these photos from Baja California, they are shown in two characteristic
behaviors—breaching (top) and "spy-hopping" or "pitchpoling" (bottom). (Photos by S. Leatherwood.)
Figure 90.—A leaping killer whale in California aquarium. Note the
distinctive coloration of the species, white on the lower jaw, the belly and
the anus, and on both sides above the anus. Note also the distinctive white
eye patch often visible on animals at sea. (Photo by D. K. Caldwell.)
Figure 91.—Killer whales have from 10 to 12 large prominent teeth,
curved slightly backwards and inwards on each side of each jaw. (Photos
from Point Mugu, Calif. by S. Leatherwood.)
Other Common Names
Mongoose (St. Vincent).
Description
False killer whales in the western North Atlantic reach a
length of at least 18 feet (5.5 m). Males are slightly larger
than females. Calves from 5 to 7 feet (1.5 to 2.1 m) may be
seen at any time throughout the year.
The dorsal fin, located just behind the midpoint of the
back, is from 7 to 16 inches (17.8 to 40.6 cm) tall, falcate, and
variable to sharply pointed on the tip. The flippers are
characterized by a broad hump on the front margin near the
middle, a characteristic which is diagnostic for the species.
The body of the species is all black except for a blaze of
gray on the belly between the flippers. This blaze varies from
barely visible to light grayish white similar to but generally
fainter than that of pilot whales. The body is long and slender,
and the head is narrow and gently tapered from the area of
the blowhole forward.
Natural History Notes
False killer whales are a social form and may occur in
herds of up to at least 100 individuals. They often jump clear
of the water and frequently ride the bow waves of vessels.
They are the only "blackfish" which are known to do so. False
killer whales feed primarily on squid and large fishes and are
notorious for their habit of stealing fish from the lines of
fishermen. The large prominent teeth may be visible on a
swimming animal.
May Be Confused With
False killer whales may be confused with killer whales,
pilot whales, or the smaller, poorly known pygmy killer whale
(p. 138) and many-toothed blackfish (p. 142).
The characteristics distinguishing the species from the
killer whale are tabularized on p. 84; its differences from the
pilot whales are summarized on p. 92.
At sea, false killer whales are distinguishable from the
other two species primarily by their larger size and
differences in coloration. False killer whales are up to 18 feet
(5.5 m) in length. Pygmy killer whales and many-toothed
blackfish reach only 8-9 feet (2.4-2.7 m) in length. Pygmy
killer whales have an extensive region of white on the belly
which may extend onto the sides and both pygmy killer whales
and many-toothed blackfish have a distinctive white region
on the lips, usually lacking or indistinct on false killer whales.
Neither of the smaller species of blackfish has been
reported to ride bow waves.
Distribution
False killer whales are widely distributed in the pelagic
tropical, subtropical, and warm temperate waters of the
western North Atlantic. They have been reported from off
Maryland south along the mainland coasts of North America,
in the Gulf of Mexico from Cuba and the Lesser Antilles, and
from the southeast Caribbean Sea. The species has been
reported from Venezuela.
Stranded Specimens
Stranded false killer whales can be positively identified
by: 1) the large size (to 18 feet [5.5 m]); 2) the slender body
tapering rapidly to a long slender head; 3) the markedly long
mouth, with from 8 to 11 large, conspicuous teeth in each side
of each jaw recalling those of the killer whale, but circular and
not, as in killer whales, elliptical; 4) the unusually shaped
flipper bulging conspicuously on the forward margin.
For comparison with "blackfish" of similar size (the pilot
whales) see p. 92 and 94.
False killer whales do not appear to occur frequently in
coastal waters, sandy bays, or estuaries, though entire herds
have stranded in such areas. Records from throughout the
range suggest that the species has an oceanic distribution.
Figure 92.—False killer whales at sea 600 miles (968.0 km) off northeastern Florida. Note the smoothly falcate
dorsal fin, pointed on the tip, and located near the midpoint of the back. Dorsal fins of this species may also be
rounded on the tip but all are sharply concaved on the rear margin. (Photo by H. E. Winn.)
Figure 93.—False killer whales are the only "blackfish" that routinely
ride the bow waves of vessels. On this animal riding on the bow wave of a
research ship, note the all-black coloration of the back, head, and sides
and the broad "hump" near the middle of the flippers on the leading edge.
(Photo 600 miles [968 km] off northeastern Florida by H. E. Winn.)
Figure 94.—A false killer whale stranded in northeastern Florida. Note
the narrow tapering head, overhanging the lower jaw by several inches,
the position and shape of the dorsal fin and the distinctive "hump" on the
leading margin of the flippers. (Photo by W. A. Huck, courtesy of
Marineland of Florida.)
Figure 95.—Entire herds of false killer whales sometimes strand themselves. In this dorsal view of an animal stranded in southeastern Florida,
note the extremely distinctive "hump" on the forward margin of the flippers and the narrow head, tapering towards the tip of the snout. (Photo
by J. Krol.)
Figure 96.—False killer whales have from 8 to 11 large, conspicuous teeth in each side of
each jaw. These teeth are often visible in swimming animals, particularly when they are
engaged in their obnoxious habit of stealing fish from the lines of fishermen. The teeth are so
distinctive that they can also be used to identify even a badly decomposed stranded
specimen. (Photo, courtesy of Sea Life Park, Hawaii.)
Other Common Names
Northern pilot whale, long-finned pilot whale, pothead,
blackfish, calling whale, caa'ing whale.
Description
Male Atlantic pilot whales reach an average length of at
least 20 feet (6.2 m). Females are slightly smaller, probably
not exceeding 18 feet (5.5 m). Young are 5-7 feet (1.5-2.1 m) at
birth.
The head is thick and bulbous, a characteristic which
reaches an extreme in the development of the head of adult
males (prompting the common name "pothead"). The flippers
are long (to one-fifth of the body length, or more) and
sickle-shaped. The tail is dorsally thickened just in front of
the flukes.
The dorsal fin of this species is one of its most distinctive
characteristics. It is low in profile, has a long base, is set far
forward on the animal's back, and is falcate to "flaglike" in
appearance. The dorsal fin of adult males reportedly has a
thicker leading edge and a rounder form than that of the
female.
Atlantic pilot whales are black on the back and sides
(prompting the common name "blackfish") but have an
anchor-shaped patch of grayish white on the chin and a gray
area on the belly, both of which are variable in extent and
intensity. Some larger animals have a gray saddle behind the
dorsal fin, though this zone of color is found more frequently
in short-finned pilot whales. Young animals are often a lighter
medium gray.
Natural History Notes
Atlantic pilot whales may occur in herds of 200 animals or
more, though herds of 50 or fewer (4-6) are more common.
They are sometimes found in association with Atlantic
white-sided dolphins.
Pilot whales are sometimes found hanging vertically in
the water with the head and part of the back out of the water
in what has been called "spy-hopping" or "pitchpoling."
Individuals frequently lobtail. Pilot whales infrequently
breach, a behavior which is usually confined to younger
animals. They do not ride bow waves.
Atlantic pilot whales feed primarily on squid but also take
cod and other fishes. A Pacific pilot whale, a closely related
species, was found by radio telemetric studies to be capable of
diving to 2,000 feet (609.6 m).
Atlantic pilot whales were formerly the object of an active
shore fishery off Newfoundland (1950-1971). In addition,
entire herds and, less frequently, individuals are sometimes
stranded.
May Be Confused With
Atlantic pilot whales are most likely to be confused with
false killer whales, with which they share the waters from off
Virginia to those off Maryland. The two species may be
distinguished by the following characteristics:
| Atlantic Pilot Whale |
False Killer Whale |
| SHAPE OF HEAD |
| Thick and often squarish in
larger animals. |
Slender, gently tapering
mouth long. |
| SHAPE OF BODY |
| Robust. |
Long and slender. |
| DORSAL FIN |
| Broad-based and falcate. |
Slender, tall, falcate, and
pointed on tip. |
| COLORATION |
| Black with gray saddle
sometimes evident behind
dorsal fin and gray region
on chin and belly. |
Mostly black with gray blaze
of variable extent and
intensity on belly between
flippers. |
| BEHAVIOR |
| Will not ride bow waves;
seldom breaches. |
May ride bow waves, often
"porpoises" and breaches. |
| RANGE |
| Temperate waters from at
least North Carolina north. |
Temperate seas from at least
Maryland south. |
In the extreme southern portion of their range, Atlantic pilot
whales may be confused with short-finned pilot whales with
which they have only a limited seasonal common range. Characters
distinguishing these species are subtle and may not be
adequate to permit them to be distinguished at sea. For purposes
of this guide it is generally that pilot whales living north
of lat. 38°N (Virginia coast) are Atlantic pilot whales and
those living south of lat. 38°N are short-finned pilot whales.
Distribution
Atlantic pilot whales, the northernmost of the two pilot
whales species, are found in winter from the Grand Banks
south as far as North Carolina and in summer from Iceland
and Greenland south to the New Jersey coast. Winter
concentrations of pilot whales may be found off the
Newfoundland coast and near Cape Cod, Mass. Atlantic pilot
whales are distributed both in coastal waters and in deep
waters off the continental shelf.
Stranded Specimens
As discussed above, individuals and groups of pilot whales
frequently strand themselves for still incompletely understood
reasons. They may be identified as pilot whales
primarily by: 1) the robust body and bulbous head, which is
often squarish in adult animals, and 2) the broad-based,
falcate dorsal fin located far forward on the back. Accurate
determination of the pilot whale species involved in the
stranding may require museum preparation of the skull and
detailed examination of its characteristics. Preliminary
identification may be made, however, based on the following:
| Atlantic Pilot Whale |
Short-Finned Pilot Whale |
| FLIPPER LENGTH |
| To one-fifth body length,
or more. |
To one-sixth body length, or
less. |
| NORMAL RANGE |
| From North Carolina north. |
From North Carolina south. |
| TEETH |
| 8-11 per row. |
7-9 per row. |
Figure 97.—A herd of Atlantic pilot whales off Massachusetts. The most distinguishing field characteristic of this species, and of their southern
cousins, the short-finned pilot whales, is the highly distinctive dorsal fin, extremely long based, low in profile, and set well forward on the animals'
backs. (Photo by W. A. Watkins.)
Figure 98.—Atlantic pilot whales frequently "lob
tail" (raise the tail flukes above the surface and slap
them against the water) (top) and pitchpole or
spy-hop (hang vertically in the water with the head
up and the tail down) (bottom). (Photos from the
North Atlantic by H. E. Winn.)
Figure 99.—North Atlantic pilot whales on the deck of a whaling station in Newfoundland. The anchor-shaped patch on the chin and the gray color of the
belly are apparently more vivid and extensive in this species than in the short-finned pilot whales. Further, the flipper is longer, measuring one-fifth of the
body length, or more, in adult animals. The flippers of short-finned pilot whales (see Fig. 102) measure one-sixth of the body length or less. (Photo by J. G.
Mead.)
Other Common Names
Blackfish (see also p. 84, 91, and 94).
Description
Male short-finned pilot whales of the western North
Atlantic reach lengths of at least 17.5 feet (5.3 m). Females
are reportedly slightly smaller than males (recorded only to
15.5 feet [4.7 m]).
The head, somewhat like that of the Atlantic pilot whales
(p. 91), is thick and bulbous, a characteristic which reaches
its extreme in the development of a flattened or squarish
appearance to the front of the head in mature males (see
Fig. 101). In very old males the melon may overhang the
mouth up to several inches. The flippers are shorter than
those of the other pilot whale species of the western North
Atlantic (thus the common name short-finned pilot whale),
reaching only one-sixth of the body length or less. The tail is
dorsoventrally thickened just in front of the flukes.
The dorsal fin, like that of the Atlantic pilot whale, is one
of the species' most distinctive characteristics. It is low in
profile, has a long base, and is set far forward on the animal's
back.
Short-finned pilot whales are all black on the back sides
and most of the belly with an anchor-shaped patch of gray on
the chin and a gray area of varying extent and intensity on the
belly. These areas are less vivid and extensive than those on
Atlantic pilot whales. Younger animals are lighter, often
medium gray.
Natural History Notes
Short-finned pilot whales are known to occur in groups of
60 animals or more, though smaller groups are more common.
They have been reported pitchpoling (spy-hopping), lobtailing,
and—rarely—breaching.
Short-finned pilot whales feed on squid and fish.
May Be Confused With
In the tropical portion of their range, short-finned
pilot whales may be confused with pygmy killer
whales (p. 138) and many-toothed blackfish (p. 142).
They may be distinguished from both species primarily
by their distinctive dorsal fin and the bulbous-to-squarish
head. Both pygmy killer whales and
many-toothed blackfish have dorsal fins, which are
more falcate, slender, and pointed on the tip, and have
longer, slenderer heads.
Throughout their range short-finned pilot whales may be
confused with false killer whales. The two species may be distinguished
by the same differences which distinguish Atlantic
pilot whales from false killer whales (p. 91).
In the extreme northern portion of their range,
short-finned pilot whales may be confused with Atlantic pilot
whales. The two species may be distinguished by differences
itemized on p. 93.
Distribution
Though short-finned pilot whales are known from
Delaware Bay, their normal range appears to extend from
Bermuda and Cape Hatteras (Virginia in summer) south
to the Venezuelan coast. They have been reported for
the Gulf of Mexico, the Caribbean, and the islands of the
West Indies.
Stranded Specimens
Stranded short-finned pilot whales may be confused with
any of the species itemized under living animals. They may be
identified as pilot whales primarily by the robust body and
bulbous head, often squarish in adult animals, and the
broad-based, falcate dorsal fin located well forward on the
animal's back. Accurate determination of the pilot whale
species involved may require museum preparation of the
skull and detailed examination of its characteristics.
Preliminary identification may be made, however, on the
basis of the following:
| Atlantic Pilot Whale |
Short-Finned Pilot Whale |
| DISTRIBUTION |
| Primarily North Carolina
north. |
Primarily North Carolina
south. |
| FLIPPERS |
| To one-fifth body length,
or more. |
To less than one-sixth body
length. |
| TEETH |
| 8-11 per row. |
7-9 per row. |
Figure 100.—Short-finned pilot whales stranded in northeastern Florida, shown here swimming in the lagoon at Marineland of Florida. This
species, like their northern cousins, the Atlantic pilot whales, have a highly distinctive dorsal fin and a bulbous head (see Figs. 97, 99). In these
photos note the variation in the shape of the head. Those of females and immature males are more rounded. Those of adult males are far more
blunted. (Photo courtesy of Marineland of Florida.)
Figure 101.—Short-finned pilot whales have from 7 to 10 teeth in each side of each jaw. The bulbous forehead of the species is far less pronounced in females
and immature males (left). The head of mature males is extremely "squarish" and may overhang the lower jaw by several inches (right). (Photos from
Aquatarium [left] and southeastern Florida by D. K. Caldwell [right].)
Figure 102.—The flippers of short-finned pilot whales reach
only about one-sixth of the body length, while those of the
Atlantic pilot whale may be one-fifth the body length or more.
Note the length of the flippers of the pilot whale in the
background, relative to its overall length. (Photo from South
Carolina by J. G. Mead.)
Other Common Names
Risso's dolphin, gray grampus, white-headed grampus,
mottled grampus, Risso's porpoise, hard knocks (St.
Vincent), white blackfish (Cape Cod).
Description
Grampus reach a maximum length of about 13 feet (4 m).
The body is robust, particularly in front of the dorsal fin, and
lacks a distinct beak. The head is somewhat bulbous and is
marked on the front by a V-shaped crease with the point
downwards, which divides the melon into two parts. The
flippers are long and pointed on the tips. The dorsal fin,
located at about the midpoint of the body, is tall, to 15 inches
(38.1 cm) or more, and distinctly falcate. The body narrows
rapidly behind the dorsal fin and the tail stock is quite
narrow. The flukes are broad, concaved on the rear margin,
and deeply notched.
The bodies of grampus are a uniform light gray at birth.
As the animals age, their color darkens to almost black with
distinctive regions of grayish white on the belly and chest.
The body of older adults is cream white or silver gray,
particularly on the head, with numerous scars, presumably
from encounters with other grampus and perhaps with the
squid, which are one of the species' major food items.
The flippers, dorsal fin, and tail flukes usually remain
dark even in adults.
Natural History Notes
Grampus are found in herds of up to several hundred
individuals and may be seen "porpoising" (leaping from the
water) as they surface to breathe, and breaching. They
sometimes ride the bow waves of a boat.
Grampus feed on fish and squid.
May Be Confused With
From a distance grampus are most easily confused with
Atlantic bottlenosed dolphins. They may be most readily
distinguished by the following differences:
| Grampus |
Atlantic Bottlenosed Dolphin |
| SIZE |
| To 13 feet (4 m). |
Rarely to 12 feet (3.7 m);
usually less than 10 feet
(3.1 m). |
| BODY COLOR |
| Young are uniform light
gray; older animals dark
with grayish regions on
chest and belly; very
old animals white and
scarred. |
Dark gray on body; lighter
gray on sides; white or pink
on belly; may appear brownish
in water. |
| DORSAL FIN |
| To 15 inches (38.1 cm);
sharply falcate; pointed
on tip |
To 12 inches (30.5 cm) less
sharply falcate; pointed on
tip. |
| HEAD COLOR AND SHAPE |
| Blunted and creased on
front; frequently all
white in larger animals. |
Uniformly brownish to gray
distinctly bottlenosed. |
| MARKINGS |
| Very often extensively
scarred. |
Less frequently scratched
and scarred. |
Distribution
Grampus are known to be distributed in temperate and
tropical seas from at least eastern Newfoundland, south at
least to St. Vincent, Lesser Antilles, and in the eastern and
northern Gulf of Mexico. The species may not be as rare as the
paucity of records suggests. Though they have been seen in
Buzzards Bay on several occasions, grampus generally have
an oceanic range and, along the Atlantic coast of North
America, may be distributed from the Gulf Stream seaward,
outside the theater of normal boating traffic.
Stranded Specimens
Stranded grampus are most readily identifiable by 1) the
presence of only seven, or fewer, teeth in each side of the
lower jaw (many of those teeth may have dropped out in older
animals and remaining teeth may be extensively worn) and
the absence of teeth in the upper jaw; 2) the presence of a
distinct crease or bifurcation in the melon on the extreme
front of the head; 3) the presence of numerous scratches and
scars all over the body; and 4) the tall, slender, sharply falcate
dorsal fin which may be more than 15 inches (38.1 cm) tall.
Figure 103.—Grampus are frequently found in small tight groups "porpoising." From a distance they may resemble the Atlantic bottlenosed dolphins,
though grampus have taller dorsal fins, blunted beakless heads, and lighter coloration. (Photo off Washington State by C. Fiscus.)
Figure 104.—Grampus off Fistler, Scotland
(top) and from Baja California in the tank of Sea
World, Inc., San Diego, Calif. (bottom). Note
the tall pointed dorsal fin, which remains dark
even in adult animals, the blunted head, which
lacks a beak, and the extensive scarring of the
body. In the photo on the right, note also the
long pointed flippers and the white head
characteristic of older animals. (Photos by
A. S. Clark [top] and courtesy of D. K. Caldwell
[bottom].)
Figure 105.—Grampus, particularly younger animals, have two regions of
grayish-white on the ventral surface, one in front of the flippers and another
beginning on the belly narrowing towards the tail. These markings closely
resemble the ventral marking of pilot whales. (Photos courtesy of Marineland
of Florida.)
Figure 106.—Stranded grampus can be readily identified. On this captive
animal note the blunted head, the distinct crease on the front of the head
(see also Fig. 107), and the extensive scarring of the body. (Photo
courtesy of D. K. Caldwell.)
Figure 107.—Grampus have seven or fewer teeth in each side of the lower
jaw. (None in the upper jaw.) Many of these teeth may have fallen out of
older specimens, and the remaining teeth may be extensively
worn. (Photo courtesy of Marineland of Florida.)
Other Common Names
White porpoise, white whale, belukha, sea canary,
marsouin blanc (Quebec).
Description
Belugas reach a maximum overall length of about 16 feet
(4.9 m). Males are slightly larger than females. In the western
North Atlantic they have been found to grow to greatest
lengths in oceanic environments near the southern
extremities of their ranges, though they are found in far
greater abundance in estuarine areas of the Arctic. Belugas
have extremely robust bodies tapering to a distinct "neck"
region and a very small head relative to body size.
They do not have a dorsal fin. Instead, along the back just
behind the midpoint there is a narrow ridge notched laterally
to form a series of small bumps. These ridges may be clearly
visible on a swimming animal.
Newborn belugas are brown. As they age, they gradually
lighten through slate gray, and by their sixth or seventh year
have assumed the all-white coloration characteristic of adult
animals.
Natural History Notes
Belugas feed on a variety of fishes (including cod and
capelin), on squid, and on a variety of benthic crustaceans.
They are frequently found in shallow bays and river
mouths, where the young are born, and occasionally ascend
rivers.
May Be Confused With
Because of their limited distribution, all-white coloration
and lack of a dorsal fin, belugas are unlikely to be confused
with any other species of cetacean.
Distribution
Belugas have been reported from the Arctic Circle south
as far as eastern Connecticut, typically in estuarine habitats,
though they do range into oceanic regions. They are most
abundant from the north shore of the Gulf of St. Lawrence
northward. They remain near the Arctic Circle and in Hudson
Bay to northern Greenland during winter, undertaking
migrations to the south in autumn, straggling to the Maritime
Provinces and as far as Connecticut. Belugas are regularly
seen in the St. Lawrence and Saguenay rivers throughout
late spring and summer. Return migrations to the north take
place in spring.
A small population in the estuary of St. Lawrence is
resident throughout the year.
Stranded Specimens
Stranded belugas are unlikely to be confused with any
other species of cetaceans. The all-white coloration, the
robust body shape with a rather small head and a distinct
neck region, and the presence of 8-11 teeth in each of the
upper jaws and 8-9 in each of the lower jaws permit positive
identification.
Figure 108.—A group of three belugas surfacing to breathe off northwestern Alaska. The animal to the right has just begun to exhale, the middle animal is
in the midst of his inhalation, and the animal on the left has completed his blow and is preparing to dive. Note the all-white coloration and, on the center
animal, the small dorsal ridge just emerging from the water. Details of the dorsal ridge are clearly visible in the inset photograph. (Photos by G. C. Ray
and K. G. Hewlett [inset].)
Figure 109.—Note the robust form and the small head of this swimming beluga off northwestern Alaska. (Photo
by G. C. Ray.)
Figure 110.—Captive belugas at Vancouver public aquarium. Note the dorsal ridge, the shape of the head and body, and the unusually shaped flippers.
(Photo by K. C. Balcomb.)
Figure 111.—Ventral view of a beluga harpooned in the northeastern Canadian Eskimo Fishery. Note the very narrow tail, just in front of the flukes, and
the robust form of the species. Belugas have 8-9 teeth in each of the lower jaws, and 8-11 in each of the upper jaws. (Photo by P. F. Brodie.)
Other Common Names
Unicorn whale (historical name not currently in use).
Description
The narwhal, also known as the unicorn whale because of
the long tusk found on adult males, is one of two
medium-sized whales found in the Arctic waters of the
northwestern Atlantic. They reach a maximum length of
from 15 to 16 feet (4.6 to 4.9 m) excluding the tusk. Newborn
calves are approximately 5 feet (1.5 m) long. Narwhals have
small rounded heads and a small mouth. Like the other
medium-sized whale in the same region, the beluga or white
whale, the narwhal has no dorsal fin. Instead, it has a series of
bumps, approximately 2 inches (5.1 cm) high along the
midline of the back in the half nearest the tail. The ridge
created by these bumps may be readily seen on a swimming
animal.
The basic coloration of the species changes slightly with
age. Young animals are uniformly dark bluish gray on the
back but rapidly begin to develop the numerous leopardlike
spots on the back and sides characteristic of adults. Those
spots rarely extend onto the belly even in old animals.
Narwhals have only two teeth. In the females, these teeth
rarely emerge from the gums. In males, one and sometimes
both of those teeth grow out the front of the snout, spiraling
in a left-hand or sinistral direction, and may reach a length
of 9 feet (2.7 m). One or two tusks may also be exposed,
however, in females.
Natural History Notes
The function of the tusk in male narwhals is unknown, but
it was this feature of the animal that earned it the name
"unicorn whale" and resulted in its extensive hunting by
whalers. During their annual migrations narwhals may
congregate but are commonly found in groups of 10 or fewer
during the rest of the year.
Narwhals feed on a variety of organisms, including cod,
rockfish, flounder, and crabs, but their diet consists primarily
of squid.
Distribution
Narwhals are found in the high arctic seas of the western
North Atlantic, primarily in Lancaster Sound and its fringes.
It has been noted that they are found in isolated pockets
within that range and are not, like the beluga, widely
distributed.
Narwhals make annual migrations in response to the
movement of the ice. During the fall as the ice begins to
form, the whales migrate to the south, sometimes reaching
the Labrador coast. In the spring they return to the
pack ice.
May Be Confused With
Narwhals are so different in coloration from the only
medium-sized cetacean which shares its range and
habitat—the beluga—that the two are highly unlikely to be
confused. Belugas are usually all white or light slate gray in
color, while narwhals are very much darker, ranging from
bluish gray to brownish, and are often covered with light
leopardlike spots. Furthermore, the body of the beluga is
more robust.
Further, swimming narwhals frequently buck their heads
up to breathe, a behavior which makes the tusk of adult males
visible and permits positive identification.
Stranded Specimens
Stranded narwhals should be easily identifiable by the
distinctive coloration and the unique characteristics of the
teeth. In adults, one or two of the teeth may develop into the
long, left-hand spiraling tusk, shown in Figures 112 and 114.
Immature animals have no teeth which are emerged.
Figure 112.—In this photo of narwhals, the origin of the name "unicorn whale" is apparent. The animal at the right, an adult male, exposes his tusk
as he surfaces aggressively to breathe. Even when this feature is not observed, however, the narwhals' mottled gray coloration makes them easy to
distinguish from the all-white belugas, with which they share a common range. Note also the dorsal ridge on the animal to the left. (Photo by D.
Lusby, courtesy of the Sea Library.)
Figure 113.—A juvenile narwhal in a tank at New York Aquarium. Though newborn animals are dark bluish
gray on the back, fading to white on the belly, note that the mottled gray coloration characteristic of adults is
well developed even in relatively young animals. The white region on the head is lanolin cream, applied to
protect the animal's skin during transport. (Photo by H. E. Winn.)
Figure 114.—A stranded male narwhal. The long unicorn tusk is the spiral extension of one of the two teeth, though the other may be exposed above the
gums in males and may even develop into a second long tusk; both teeth of females are normally buried in the gums and rarely emerge. Note the highly
distinctive dorsal ridge, near the midpoint of the back. (Photos by D. Lusby, courtesy of the Sea Library.)
Other Common Names
Spotter, Gulf Stream spotted dolphin, spotted porpoise,
long-snouted dolphin.[11]
Description
Atlantic spotted dolphins reach a maximum adult length
of 7.5, perhaps 8 feet (2.3 to 2.4 m). They are generally more
robust in body shape than the other species of Stenella,
closely resembling Atlantic bottlenosed dolphins in that
regard, though the Atlantic spotted dolphins tend to be more
slender.
The dorsal fin is distinctly back-curved and pointed on the
tip, also closely resembling that of the Atlantic bottlenosed
dolphin.
As the common name suggests, the Atlantic spotted
dolphins are marked dorsally with numerous grayish-white
spots on a darker background and ventrally with dark spots
on a lighter background, though the extent of the spotting
and the additional details of coloration change with age.
Immature animals lack spots completely. They are dark
gray or purplish gray on the back, becoming lighter gray on
the sides and white on the belly. The cape along the back is
distinctly separated from the lighter gray coloration of the
sides. The flippers and the trailing edge of the flukes are
darker than the rest of the body.
As they age, the Atlantic spotted dolphins develop
grayish-white spots, first low on the sides, spreading
upward. During this stage, the cape becomes less distinct,
and dark spotting begins to develop on the belly, the spots
increasing in number with increasing age. In adult animals,
the belly is often extensively covered with dark blotches but
never becomes completely black. The lips may be white, and
the beak is characteristically tipped with white, a feature
which may aid in identification at sea.
The Atlantic spotted dolphins have a spinal blaze and a
light line which extends from the flipper to the eye.
Natural History Notes
Little is known of the natural history of the Atlantic
spotted dolphins. The species occurs in herds of up to several
hundred individuals, though groups of 50 or fewer (6-10) are
more common. They are often seen jumping clear of the water
and habitually ride the bow wave of moving vessels. As they
do, the distinct cape or band of purplish gray on the back of
younger animals and the spotting pattern of older animals
may be visible.
Atlantic spotted dolphins feed primarily on squid but may
also take carangid fishes, small eels, herring, or anchovies.
May Be confused With
Atlantic spotted dolphins, particularly young animals,
may be easily confused with Atlantic bottlenosed dolphins
because of the similarities in color pattern and general body
shape. However, the Atlantic spotted dolphins have
considerable purplish gray in their background colors and the
Atlantic bottlenosed dolphins are more dark gray to brownish
gray. This along with considerable differences in the overall
sizes of the two species should permit positive identification.
In general, the key differences between spotted and
bottlenosed dolphins are as follows:
| Atlantic Spotted Dolphin |
Atlantic Bottlenosed Dolphin |
| MAXIMUM SIZE |
| To 7.5-8 feet (2.3-2.4 m). |
To 8-10 feet (2.4-3.1 m)
inshore, to as much as 12 feet
(3.7 m) offshore. |
| BODY COLOR |
| Dark purplish gray on back;
lighter gray on sides and
belly; body becomes
increasingly spotted with age. |
Dark gray on back; lighter
gray on sides; white or pink
on belly (old animals may
have a few spots on belly,
but most are not spotted). |
| HEAD AND BEAK |
| Head more slender; beak
longer; lips and top of snout
often white. |
Head robust; beak short;
beak usually uniformly gray
(older animals' beak may be
white at tip). |
| NORMAL DISTRIBUTION |
| Usually found more than 5
miles offshore; most common
inside 100-fathom curve. |
Usually more coastal, often
ascending rivers and entering
lagoonal and estuarine
areas. |
Young Atlantic spotted dolphins are so similar in
appearance to the Atlantic bottlenosed dolphins that the
frequent reports of mixed schools of the two species are
probably occasioned by groups of spotted dolphins which
include some young, still unspotted animals.
Atlantic spotted dolphins might also be confused with
bridled dolphins. The two can be most readily distinguished
by the following characteristics:
| Atlantic Spotted Dolphin |
Bridled Dolphin |
| BODY SHAPE |
| Usually robust, often like
that of the Atlantic
bottlenosed dolphin. |
More slender, more like
that of the Atlantic striped
dolphin. |
| BODY COLOR |
| Spotted; purplish gray on
back; lighter gray on sides
and belly becoming
increasingly spotted with age.
As animals becomes more
spotted, cape become less
distinct. Body has spinal
blaze and light line from
flipper to eye. |
Spotted; side of head light
gray; body has stripe from
flipper to corner of mouth,
though the stripe tends to
fade as spotting increases.
Cape on top of head more
distinct that on Atlantic
spotted dolphin. Body has no
spinal blaze. |
At sea the Atlantic spotted dolphins may also be confused
with rough-toothed dolphins (p. 135).
Distribution
Atlantic spotted dolphins are a common species in the
continental waters of the tropical and warm temperate
western North Atlantic. Although they are far more
abundant south of Cape Hatteras, they have been reported
from the latitude of Cape May, N.J. (some fishermen claim to
have seen them even further north) south through the Gulf of
Mexico and the Caribbean to Venezuela. Atlantic spotted
dolphins may be replaced around the West Indies by the
bridled dolphin.
Within this range, the Atlantic spotted dolphins appear to
be generally restricted to the waters outside the 100-fathom
curve, most commonly more than 5 miles offshore. However,
populations in the Gulf of Mexico move inshore in the late
spring, and may approach close to shore during spring and
summer.
Stranded Specimens
Stranded Atlantic spotted dolphins may be difficult to
distinguish from bridled dolphins. If the color pattern is still
clearly visible, the differences in coloration described above,
particularly those of the head, and the presence or absence of
a spinal blaze may be used. But since external appearance
other than coloration are often very similar, specimens
should be photographed from as many aspects as possible and
the entire specimen or the roughed-out complete skeleton
transported to a museum for preparation and examination.
Tooth counts recorded for the two species to date are also
very similar.
Figure 115.—Atlantic spotted dolphins beside a research vessel off Beaufort, N.C., September 1965. Adults of this species can be identified by
the spotting pattern and the white coloration of the lips. (See also bridled dolphin, p. 108.) Young animals which lack spots may be confused
with the Atlantic bottlenosed dolphins though they are smaller and are purplish gray on the back. (Photo by G. T. Green.)
Figure 116.—A side view of two female Atlantic
spotted dolphins from off St. Augustine, Fla. in the
tank at Marineland of Florida. Note the tall falcate
dorsal fin, pointed on the tip and varying slightly in
shape between the two individuals, and the spots on
the body. (Photo by S. Leatherwood.)
Figure 117.—A series showing the development of the color pattern of the Atlantic spotted dolphins from Florida. Newborn or young animals are dark
purplish gray on the back, grading to immaculate white on the belly. As they mature, animals develop light spots, first on the lower sides, then higher on the
back, and dark spots on the belly. As spotting increases, the cape becomes less distinct. (Photos by A. Solis [a], D. K. Caldwell [b, c], and courtesy of
Marineland of Florida [d, e, f].)
Figure 118.—Juvenile Atlantic spotted dolphins at
sea in the southeastern Caribbean. Although
spotters can be either relatively short-snouted and
chunky or long-snouted and slightly built, the
spinal blaze, flipper-to-eye stripe, white lips, and
falcate dorsal fin can be used to identify
them. (Photo by D. Poppe.)
Figure 119.—A captive Atlantic spotted dolphin
from off St. Augustine, Fla. This species has from
30 to 36 teeth in each upper jaw and from 28 to 35 in
each lower jaw, fewer than all other Stenella except
perhaps the bridled dolphin, fewer than the
saddleback dolphins, but more than the Atlantic
bottlenosed dolphins. (Photo by S. Leatherwood.)
Other Common Names
Bridled spotted dolphin, Cuvier's dolphin, gamin (St.
Vincent), bridled porpoise.
Description
Bridled dolphins, the second species of spotted dolphins in
the western North Atlantic, reach an adult length of at least
7 feet (2.1 m). Like the other, the Atlantic spotted dolphin
(p. 104), bridled dolphins are characterized by light grayish-white
spots on the dark dorsal portions of the body and dark
spots on the light ventral surface. Other details of the
coloration differ somewhat. Bridled dolphins are dark gray
on the back, fading to lighter gray on the sides and belly.
They lack the spinal blaze characteristic of Atlantic spotted
dolphins. Except on the head, the border between the back
and side colors is indistinct. On the head, the cape (the dark
color of the top of the head) is distinct. In the light gray of
the side of the head are the markings from which the species
derives its common name, "bridled dolphin." These are a
black circle around the eye with an extension to the junction
(apex) of the rostrum and the melon (present in nearly all
dolphins) and a broad black stripe from the origin of the
flipper to the corner of the mouth. This mouth-to-flipper
stripe tends to fade as spotting increases. Both the upper
and lower lips are white or pinkish.
Natural History Notes
Virtually nothing is known of the natural history of
bridled dolphins except that they have been observed in small
herds of from 5 to 30 individuals and sometimes ride the bow
wave of a vessel.
May Be Confused With
At sea, bridled dolphins may be confused with Atlantic
spotted dolphins or spinner dolphins. Differences by which
they may be distinguished from the first are tabularized on
p. 105. Differences between spinner and bridled dolphins
permitting identification at sea are as follows:
| Bridled Dolphin |
Spinner Dolphin |
| COLORATION |
| Distinct cape on top of head;
side of head light gray;
distinct stripes from flippers
to corner of mouth and from
dark circles around eye to
apex of melon. |
Dark gray on back; tan or
yellowish tan on sides; white
on belly. |
| BEAK |
| Shorter and more slender; all
black; lips white. |
Extremely long and slender;
dark gray to black on top,
white below; lips black. |
| DORSAL FIN |
| Uniformly dark gray. |
Often lighter gray in middle,
dark around border. |
Distribution
Bridled dolphins occur in tropical and subtropical waters
primarily near coastal areas and islands, but are best known
from the West Indies. They have been reported from the
Antilles, from Texas, and from Florida north to North
Carolina. It has been speculated that this species replaces the
Atlantic spotted dolphin around the West Indies.
Bridled dolphins have not yet been described from the
South American coast.
Stranded Specimens
Bridled dolphins have from 29 to 34 teeth in each upper
jaw and from 33 to 36 in each lower jaw. They can be
distinguished from spinner dolphins, which have 46-65 teeth
in each jaw, by this character alone.
They may be distinguished from spotted dolphins only if
the color pattern of the head is clearly visible. If it has faded,
the specimen will probably require museum preparation and
examination before it can be positively identified.
Figure 120.—A bridled dolphin harpooned in the commercial whale fishery off St. Vincent, Lesser Antilles. If the color pattern has faded, bridled dolphins
cannot be readily distinguished from the Atlantic spotted dolphins and must be sent to a museum for preparation and examination of the skull and
skeleton. (Photo by W. A. Huck, courtesy of Marineland of Florida.)
Figure 121.—A bridled dolphin from St. Vincent, Lesser Antilles. Note the dark cape of the back, the
lighter side, and the dark stripes from the eye to the snout (found in most dolphin species) and the flipper to
the gape, a feature which fades as the animal's spotting increases. Together these two features comprise
the "bridle" from which the common name derives. Note also the white lips and the white lower jaw.
(Photo by J. R. Sullivan.)
Other Common Names
Long-snouted dolphin, long-beaked porpoise, spinner
porpoise, rollover (St. Vincent).
Description
Spinner dolphins reach a maximum length of about 7 feet
(2.1 m). The body is slender. The beak varies from extremely
long and slender (Fig. 123) to relatively short (Fig. 125); the
beak is usually dark on top and clean white below, though
there may be some white above. The tip of the snout and the
lips are distinctly black, while those of both species of spotted
dolphins are light. The back is dark gray to black, the sides
are tan to yellowish brown, and the belly is white. Some of the
larger animals appear almost all black with faint, light
speckling. The dorsal fin is generally moderately falcate, but
may be almost triangular in adult males. It is often a lighter
gray near the middle, bordered by black or dark gray.
Natural History Notes
Spinner dolphins derive their common name from
their habit of leaping clear of the water and spinning
on their longitudinal axis. The reasons for this behavior
are unknown. Individuals may rotate 2 times, or more,
in one leap but spinning behavior is not observed as
frequently in the western North Atlantic as it is in the
eastern tropical Pacific.
Spinner dolphins occur in herds of up to several hundred
individuals and are often seen jumping clear of the water,
working the sea surface into a froth. They frequently come to
the bow of a boat from considerable distances to ride in the
bow wave and may ride for protracted periods.
May Be Confused With
Spinner dolphins may be confused with saddleback
dolphins. Both species occur in large herds and often come to
moving vessels to ride the bow wave. The two can be
distinguished, however, by these differences:
| Spinner Dolphin |
Saddleback Dolphin |
| COLORATION |
| Dark gray on back; tan or
yellowish tan on sides; white
on belly; lacks crisscross
pattern on sides; distinct
black stripe from flipper to
eye. |
Dark gray to brownish gray
on back; white on belly with
crisscross or hourglass pattern
of tan to yellow on sides;
distinct black stripe from
flipper to middle of lower
jaw. |
Spinner dolphins might also be confused with bridled
dolphins, but may be distinguished by the differences
summarized on p. 108.
Distribution
Spinner dolphins are distributed in oceanic and coastal
tropical waters. Though one specimen was collected from
South Carolina, they have been more frequently reported
from both coasts of Florida, the Gulf of Mexico, the
Caribbean, and the West Indies. They have also been
reported from Venezuela. They are said to be the most
abundant dolphin species from the southeastern Caribbean.
Some Pacific spinner dolphins are distributed in oceanic
zones. Atlantic spinners may be abundant in offshore tropical
waters as well.
Stranded Specimens
Stranded spinner dolphins are most readily identified by
the extremely long rostrum and the 46-65 teeth, far more
than any other species of dolphin. Note that the striped
dolphins may have from 43 to 50 teeth per side in each jaw.
However, striped dolphins are decidedly larger (to about 9
feet [2.7 m]), have a shorter beak, and are distinctly marked
with dark stripes from the eye to the flipper, from the eye to
the anus, and from the area behind the dorsal fin forward,
towards but not reaching the head.
Saddleback dolphins also have from 40 to 50 teeth on each
side but are also easily distinguishable by the differences in
coloration discussed above for living animals at sea.
Figure 122.—Spinner dolphins occur in large herds
in tropical waters. As illustrated by these photos of
animals off Venezuela in 1969, spinner dolphins
often leap clear of the water and may come to a
moving vessel from considerable distances away to
frolic in its bow wave. (Photo by M. Bartlett.)
Figure 123.—A spinner dolphin jumping
close beside a research vessel off the Virgin
Islands. The distinctive color pattern (gray
on the back, tan on the sides, and white on
the belly) is clearly visible. The black-tipped
rostrum and the black lips are key
characters to this species. (Photo by C.
McCann.)
Figure 124.—Spinner dolphins are active bow
riders and may stay with a vessel for long periods of
time. (Photo from off the Virgin Islands by H. E.
Winn.)
Figure 125.—Although all spinner dolphins so far examined have the same basic characteristics, the degree of expression of those characteristics varies
from individual to individual or area to area. These small short-snouted dolphins (those on bottom stranded near St. Petersburg, Fla. and maintained
alive by the Aquatarium in that city, and those on top photographed at sea, off the northwestern Africa coast in 1972) are spinners, although their
classification is uncertain. There may be several species or geographical races of spinners in the Atlantic. (Photos courtesy of W. F. Perrin [top] and
Aquatarium [bottom].)
Figure 126.—A spinner dolphin harpooned in the fishery at St. Vincent, Lesser Antilles. Even after subtle aspects of the color pattern have faded, this
species can be readily identified by the 46-65 teeth in both upper and lower jaws and by the distinctly black lips and black-tipped rostrum. (Photo by W. A.
Huck, courtesy of Marineland of Florida.)
Other Common Names
Euphrosyne dolphin (Stenella styx), Meyen's dolphin,
blue-white dolphin, Gray's dolphin, striped porpoise,
streaker porpoise.
Description
The striped dolphin is a widely distributed relative of the
spinner and the Atlantic spotted dolphins, though it more
closely resembles saddleback dolphins than either of these
two species. It reaches a maximum length of about 9 feet (2.7
m) and is characterized by a series of distinctive black stripes.
One band of black begins near the eye and extends down the
side of the body to the area of the anus. (A small secondary
stripe originating with this band turns off and disappears in
the white coloration of the side just above the flippers.) A
second band of black extends from the eye to the flipper.
Some workers have contended that striped dolphins are
separable into distinct species depending on whether the
eye-to-flipper stripe has one (S. coeruleoalba) or two (S. styx)
components.
Most individuals have an additional distinctive finger of
black coloration which extends from the black coloration
behind the dorsal fin forward towards and about halfway to
the eye. It is this feature which is most distinctive in animals
riding the bow or leaping clear of the water. The back is dark
gray to bluish gray, the sides are lighter gray, and the belly is
white.
Natural History Notes
Though little is known of this species, it has been reported
in herds of up to several hundred individuals and apparently
exhibits behaviors very similar to those of the saddleback
dolphins (p. 116), frequently jumping clear of the water.
Atlantic and Mediterranean animals have been reported to
bow ride.
May Be Confused With
This species is most likely to be confused with the
saddleback dolphin, which it closely resembles. The two may
be distinguished by the following characteristics:
| Striped Dolphin |
Saddleback Dolphin |
| LENGTH |
| To about 9 feet (2.7 m) or
more. |
Seldom greater than 7.5 feet (2.3 m). |
| COLORATION |
| Back from light gray to dark
gray to bluish gray; sides
gray; belly gray or white;
distinctive black lateral
stripping from 1) eye to
flipper, 2) eye to anus, and 3)
dark color behind dorsal fin
forward, towards but not
reaching head. |
Back basically black or
brownish; distinct white
chest or belly patch;
hourglass or crisscross
pattern on the sides;
distinct black stripe from
flipper to middle of lower
jaw. |
Distribution
Striped dolphins are widely distributed in the temperate,
subtropical, and tropical seas of the western North Atlantic.
They have been reported from at least Halifax, Nova Scotia,
south as far as Jamaica. (Additional records, purportedly
from southern Greenland, involved a museum specimen.
Since striped dolphins of the eastern North Atlantic are rare
north of England, the species occurrence near Greenland
would be highly improbable.) Individuals have recently been
reported from the Gulf of Mexico.
Despite this wide distribution, striped dolphins appear to
prefer warmer waters and are probably normally confined to
the Gulf Stream or the waters off the continental slope.
Individuals appearing to the north of the range seem to have
ventured northward with fingers of warm water.
Stranded Specimens
Stranded striped dolphins should be readily identifiable
by the highly distinctive patterns of lateral striping
discussed above for living animals. If the color pattern has
faded, they may still be identified by their size, larger than
other dolphin species of similar appearance, and the
relatively large number of teeth (43-50 per side in both
upper and lower jaws). Only the spinner dolphin, much
smaller in body length and having a much longer beak, has
more teeth (46-65 per side in each jaw).
Figure 127.—Despite some similarities in appearance and behavior to saddleback dolphins, striped dolphins can be readily
identified by the prominent dark stripes on the side of the body. These striped dolphins were photographed between the
Caribbean Islands of Curacao and Bonaire in 1972. (Photo by D. Poppe.)
Figure 128.—When they ride the bow, the most apparent characteristic of striped dolphins is usually the dark streak beginning in
the black coloration behind the dorsal fin and extending forward towards but not reaching the head. This stripe is not always
present, however, and the species may sometimes appear uniformly pale gray from a distance. (Photo from the tropical Atlantic
by H. E. Winn.)
Figure 129.—Stranded striped dolphins. Note the distinctive black stripes 1) eye to flipper, 2) eye to anus, and 3) (on top animal) from black behind
dorsal fin forward towards but not reaching the head. Some workers contend that striped dolphins are separable into two species, depending on
whether the eye-to-flipper stripe has one (Stenella coeruleoalba) or two (S. styx) components. Others contend that the two belong to the same species
(S. coeruleoalba). Striped dolphins have from 43 to 50 teeth in each upper and lower jaw. (Photos from Japan by W. E. Schevill [top] and from Indian
Rocks Beach, Fla. by W. A. Huck, courtesy of Marineland of Florida [bottom].)
Other Common Names
Saddleback porpoise, common dolphin, crisscross
dolphin.
Description
Saddleback dolphins reach a maximum overall length of
about 8.5 feet (2.6 m) though most individuals are less than
7.5 feet (2.3 m) long. Males are slightly larger than females of
the same age.
The body shape varies slightly but usually closely resembles
that of the striped dolphin (p. 113). The dorsal fin
varies from nearly triangular to distinctly falcate and is
pointed on the tip. It is sometimes all black and sometimes
black on the borders with a lighter grayish region of varying
size near the middle.
The back is basically black or brownish black, but this
coloration and the extent of the striping patterns that form
the impression of a saddle and the degree of color distinction
between the different zones are highly variable.
The chest and belly are cream white to white and are the
most distinctive features from a distance. Up close, the sides
will be seen to be distinctly marked with an hourglass or
crisscross pattern of tan or yellowish tan. This crisscross
pattern is diagnostic for the species.
The rostrum is intermediate in length and shape between
that of the spinner and that of the striped dolphin and is often
black with a white tip.
Natural History Notes
Saddleback dolphins are often seen in herds of a thousand
or more and are often very active, many animals leaping clear
of the water at any time. Like spinner dolphins, saddleback
dolphins are active bow-riders and often come to the boat
from considerable distances. Once on the bow they often ride
for extended periods of time.
Saddleback dolphins feed on squid and on a variety of
fishes, including anchovies, myctophids, and hake.
May Be Confused With
Saddleback dolphins might easily be confused with
striped dolphins and must be examined closely to be
distinguished from them. Primary differences apparent in
encounters at sea are as follows:
| Saddleback Dolphin |
Striped Dolphin |
| COLORATION |
| Back basically black or
brownish; distinct white
chest or belly patch; hourglass
or crisscross pattern on
sides, some tan to yellowish
tan; distinct black stripe
from flipper to middle of
lower jaw. |
Back from light gray to dark
gray to bluish gray; sides
gray; belly gray or white;
distinctive black lateral
striping from 1) eye to
flipper, 2) eye to anus, and
3) dark color behind dorsal
fin forward, towards but not
reaching head. |
| LENGTH |
| To 7.5 feet, rarely to 8.5 feet
(2.3-2.6 m). |
To 9 feet (2.7 m). |
From a distance, saddleback dolphins might also be
confused with spinner dolphins because of the habits of both
species of congregating in large schools with much jumping
and splashing. Both species ride the bow wave, and close
examination should permit positive identification using the
following characteristics:
| Saddleback Dolphin |
Spinner Dolphin |
| COLORATION |
| Dark gray to brownish gray
on back; white on belly with
crisscross or hourglass pattern
of tan to yellowish tan
on side; distinct black stripe
from flipper to middle of
lower jaw. |
Dark gray on back; tan or
yellowish tan on sides; white
on belly; lacks crisscross
pattern on sides; distinct
black stripe from flipper to
eye. |
Distribution
Saddleback dolphins are widely distributed in the
temperate, subtropical, and tropical waters of the western
North Atlantic Ocean. They have been reported off
Newfoundland, Iceland, Nova Scotia, and the coast of
Massachusetts, south along the coast of North America to the
Caribbean (West Indies and Jamaica), in the Gulf of Mexico,
and from South American waters at least to Margarita Island,
Venezuela.
The species' occurrence in the more northerly portions of
this range during the summer and early fall months appears
to coincide with the intrusion of warm waters into those
areas. They are not uncommon off Nova Scotia in summer
and fall and are casual members of the marine mammalian
fauna of the remaining Maritime Provinces during
that period.
In previous years, saddleback dolphins were not
uncommonly encountered by collectors of Marineland of
Florida working the northeast coast of Florida, but the
species has been conspicuously absent since about 1960.
Reasons for this apparent shift of range are unknown.
Stranded Specimens
Saddleback dolphins have from 40 to 50 small, sharply
pointed teeth in each side of both the upper and lower jaws.
These numbers overlap with only those of the striped and
spinner dolphins (with 43-50 and 46-65, respectively).
Saddleback dolphins should be readily distinguishable from
both these species by the features outlined under the
descriptions of living animals and distinguishable from the
bridled dolphins by the distinctive markings on the head of
the two species (see Figs. 121 and 134).
Figure 130.—Saddleback dolphins captured off St. Augustine, Fla., shown in the tank at Marineland of Florida. The highly distinctive crisscross
or hourglass pattern of tan or yellowish tan on the sides is clearly visible. Note also the light tip of the snout and the dark line from the center of
the lower jaw to the flipper. This last characteristic readily distinguishes the saddleback dolphin from the striped dolphin, in which the black
stripe begins at the corner of the mouth rather than near the center of the lower jaw. (Photos courtesy of Marineland of Florida.)
Figure 131.—Saddleback dolphins on the bow of a ship off Massachusetts in 1966. The color pattern, including the dark brownish-gray back, the
crisscross pattern on the sides, and the white belly, are clearly visible. The light tip of the snout helps distinguish this species from the spinner
dolphins, which have a black-tipped snout. (Photo by E. Wheeler.)
Figure 132.—The distinctive crisscross pattern of the sides of the saddleback dolphins is clearly visible even when comparatively little of the animal is
seen. Note the falcate dorsal fin, which often, as here, is dark on the border, lighter near the center. (Photo by R. K. Brigham, courtesy of National
Marine Fisheries Service.)
Figure 133.—Saddleback dolphins frequently jump clear of the water and may reenter in a variety of ways: 1) smoothly, head first; 2) with a chin slap; 3)
with an accompanying tail lob; or 4) on the sides or back with a splash. This habit enables them to be spotted from a considerable distance. When stressed,
herds bunch tightly together, like the group in the bottom photo. (Photos from off Virginia by J. G. Mead [top] and off San Diego, Calif. by S. Leatherwood
[bottom].)
Figure 134.—A saddleback dolphin stranded on Westerly Beach, R.I. The origin of
the common name "crisscross dolphin" is evident in the color pattern of the side. Note
also the distinctive black stripe from the center of the lower jaw to the origin of the
flipper. (Photo courtesy of H. E. Winn.)
Other Common Names
Sarawak dolphin, Bornean dolphin, Fraser's porpoise.
Description
Fraser's dolphins reach an overall length of at least 8 feet
(2.4 m). They are extremely short-beaked and have a
pronounced dark stripe, similar to that found on the striped
dolphin, extending from the rostrum to the area of the anus.
They are robust in build and have rather small flippers and
dorsal fin relative to body size. The dorsal fin is slender,
falcate, and pointed on the tip. The body is gray on the back
and white on the belly. The color of the side is dominated by
the striping pattern. A cream-white band beginning high on
the rostrum extends above and past the eye, continues
towards the tail, and finally dissipates in the body color above
the anus. Just below and parallel to this cream-white band is a
black one extending from the area of the eye to the anus. A
second cream-white band below and parallel to this dark strip
separates the darker gray coloration of the side from the
white coloration of the belly. The flippers are dark above and
below.
Natural History Notes
The little that is known of the natural history and behavior
of the species may be summarized as follows: Fraser's
dolphins occur in groups of up to at least 500 animals and in
the Pacific are occasionally seen with spotted dolphins
(Stenella attenuata). From all accounts, they are not
uncommon in certain areas of the tropical Pacific and off
South Africa.
Fraser's dolphins appear to be deep divers. They are
aggressive swimmers and, when they surface to breathe,
often charge to the surface, creating a spray from their heads.
They have also been reported leaping clear of the water.
May Be Confused With
Fraser's dolphin is intermediate in form between
Lagenorhynchus and Delphinus delphis (thus the composite
name Lagenodelphis). Because the species is apparently
limited to tropical waters, however, and because of the
prominent stripe on the side of the body, Fraser's dolphins
are more likely to be confused with the striped dolphins
(p. 113). The two species can be distinguished at sea by
several characteristics:
| Fraser's Dolphin |
Striped Dolphin |
| COLORATION |
| Single broad black stripe
from beak and eye back to
area of anus. |
Color dominated by series of
stripes from: 1) eye to anus;
2) eye to flipper, and 3)
black behind dorsal fin
forward, towards but not
reaching the head. |
| BEAK |
| Extremely short and indistinct. |
Longer, much more distinctive. |
| BODY SHAPE |
| Robust, particularly in front
of dorsal fin. |
Slenderer. |
| FLIPPERS |
| Small, dark in color, and
originating in light color of
sides. |
Longer, sometimes lighter
on upper surface; note stripe
from front of flippers to eye. |
| DORSAL FIN |
| Small, slender, slightly
falcate, and pointed on top. |
Taller dorsal fin, broader at
base. |
Distribution
Although Fraser's dolphins have yet to be described for
the western North Atlantic Ocean, they are included here as
"possibles" because of the recent discovery that their range is
far more extensive than previously known. Records to date
have been limited to offshore tropical waters.
The species was first described in 1956 from the remains
of a beach-washed specimen from Sarawak in the South China
Sea. Since that time specimens have been collected from the
eastern tropical Pacific, and others have stranded in such
widely divergent localities as Australia, South Africa, and
Japan. Recent summaries have added sighting records from
the Central Pacific, near the Phoenix Island, from northwest
of the Galapagos Islands, and from South African
waters.
Stranded Specimens
Stranded Fraser's dolphins should be readily identifiable
by 1) distinctive coloration of the body; 2) short, indistinctive
beak; and 3) robust form. The only other species of small
dolphins with beaks of similar length and general appearance
are the Atlantic white-sided and white-beaked dolphins (p.
123 and 126); these dolphins, both with far more northerly
ranges, have 30-40 and 22-28 teeth in each side of each jaw,
respectively, while Fraser's dolphins have from 40 to 44
teeth in the upper jaw and from 39 to 44 in the lower jaw.
Figure 135.—Fraser's dolphins, like these photographed off the Phoenix Islands in the Pacific (top) and this one off the Philippines (bottom), are definitely
identifiable in their tropical range by the short snout, the dark flank stripe and the small dorsal fin and flippers. They may reach 8 feet (2.4 m), or more, in
length and occur in herds of at least 500 animals, sometimes with spinner dolphins or Atlantic spotted dolphins. (Photos by K. C. Balcomb [top] and T.
Hammond [bottom].)
Figure 136.—Fraser's dolphins from the eastern tropical Pacific: adult (top and inset)
and calf (bottom). Note the distinctive black lateral strip and the extremely small
flippers and dorsal fin. (Photos by R. Garvie [top and inset] and S. Leatherwood
[bottom].)
Other Common Names
Atlantic white-sided porpoise, jumper (Newfoundland).
Description
Atlantic white-sided dolphins reach about 9 feet (2.7 m) in
maximum length and are robust in form with a small but
distinct beak (less than 2 inches [5.1 cm] long).
The dorsal fin is tall, distinctly back curved, and pointed
on the tip. The tail stock is extremely thick and does not
narrow laterally until very near the tail flukes.
The back is distinctly black, the belly white. The sides
have zones of gray, tan, and white.
The single most distinctive feature of Atlantic white-sided
dolphins is an elongated oval zone of white and yellowish
white along the sides from just below the dorsal fin to the area
above the anus. These patches of lighter coloration, clearly
demarcated from each other and from the surrounding
coloration, are frequently visible simultaneously with the
dorsal fin as the animals roll at the surface to breathe. Even
alone this feature permits positive identification of the
species. The dorsal fin is often part gray, part black. The beak
is all black.
Natural History Notes
Atlantic white-sided dolphins are known to congregate in
herds of perhaps a thousand animals, though smaller herds
are far more common. The species is often wary of ships and
does not ordinarily ride the bow wave. Like a number of other
species, white-sided dolphins have been reported in
association with Atlantic pilot whales.
May Be Confused With
At sea, Atlantic white-sided dolphins are most likely to be
confused with the white-beaked dolphins, with which they
overlap in distribution. Though they are very similar in
general appearance, the two can be distinguished in the
following ways:
| Atlantic White-Sided Dolphin |
White-Beaked Dolphin |
| COLORATION |
| Elongated band of yellowish
white and white along side,
visible behind and below
dorsal fin as animal rolls. |
Two grayish areas—one in
front, the other below and
behind dorsal fin, visible as
animal rolls. |
| BEAK |
| All black. |
Sometimes white in parts of
range though western Atlantic
animals are usually dark. |
| MAXIMUM SIZE |
| To 9 feet (2.7 m). |
To 10 feet (3.1 m). |
| DORSAL FIN |
| Often part black, part lighter
gray. |
Uniformly dark. |
Distribution
Atlantic white-sided dolphins are distributed, primarily
offshore, in the cool waters between the Gulf Stream and the
Labrador Current. They have been observed from Hudson
Canyon, off New York City, north to southern Greenland and
perhaps Davis Straits. Their normal range shares a southern
boundary with the white-beaked dolphin but does not extend
as far to the north.
Stranded Specimens
In addition to the features described above for living
animals at sea, stranded Atlantic white-sided dolphins can be
distinguished from white-beaked dolphins by the following:
| Atlantic White-Sided Dolphin |
White-Beaked Dolphin |
| NUMBER OF TEETH |
| 30-40 per side per jaw,
sometimes more in upper. |
22-28 per side per jaw; have
larger individual teeth—to 6
mm in diameter. |
| FLIPPERS |
| Lower portion of forward
margin more curved. |
Lower portion of forward
margin less acutely curved. |
| VENTRAL COLOR |
| White coloration of belly
extends high onto sides of
body. |
White coloration of belly
extends to lower jaw but not
above flippers on sides. |
| CAUDAL CRESTS |
| Tail stock strongly compressed
laterally; taller, narrows
rapidly just in front of flukes. |
Tail stock less laterally
lcompressed, tapers more
gently towards tail flukes. |
Figure 137.—Atlantic white-sided dolphins at sea between Cape Cod, Mass. and Nova Scotia. This species can be positively identified by the
elongated zone of white and the adjacent region of tan or yellowish tan below and behind the dorsal fin, visible even in the fast-swimming animal in
the bottom picture. The top photo illustrates the origin of the Newfoundland common name "jumper." (Photos by K. C. Balcomb [top] and H.
E. Winn [bottom].)
Figure 138.—An Atlantic white-sided dolphin off the eastern Canadian coast. These
animals do not usually ride the bow wave, but when they can be examined at close
range, they can be readily distinguished from their more northerly cousins, the
white-beaked dolphins, by their highly distinctive color pattern. (Photo by P. B.
Beamish.)
Figure 139.—The highly distinctive pattern of the Atlantic white-sided
dolphins is clearly visible in this animal stranded in Scotland. Even if the
color pattern has faded, however, this species should be easy to identify.
The 30-40 teeth in each of the upper and lower jaws permit distinction
from the white-beaked dolphins, which have only about 22-28 per side in
each jaw. (Photos by B. Tullock, courtesy of A. S. Clarke.)
Other Common Names
White-beaked porpoise, squidhound (Newfoundland).
Description
White-beaked dolphins reach a maximum overall length of
about 10 feet (3.1 m). The body is robust in form with a tall,
uniformly dark-gray dorsal fin, and a short but distinct beak
which, as the common name implies, is often light gray to
white above and below, at least in European waters. The
beak of animals in the western Atlantic populations is less
frequently white. The back and sides are basically dark gray
to black, and the belly is white to light gray.
Swimming white-beaked dolphins can be most readily
identified by the two areas of pale coloration on the sides, one
in front of and another below and behind the dorsal fin. These
areas are clearly visible from a ship or aircraft as the animals
roll at the surface.
Natural History Notes
White-beaked dolphins may sometimes occur in herds of
up to 1,500 individuals. Like their cousins, the Atlantic
white-sided dolphins, they do not commonly ride the bow
waves of vessels.
White-beaked dolphins feed on squid, octopus, cod,
herring, capelin, and sometimes on benthic crustaceans.
May Be Confused With
In their northerly range white-beaked dolphins are likely
to be confused with only the Atlantic white-sided dolphins.
The most distinctive features of white-beaked dolphins are 1)
the two areas of paleness described above, 2) the prominent,
dark gray dorsal fin, and sometimes 3) the white beak. Other
features by which the two species may be distinguished in the
brief encounters typical at sea are tabularized on p. 127.
Distribution
White-beaked dolphins are the more northerly of the two
species of Lagenorhynchus in the western North Atlantic.
They are found from Cape Cod, Mass., north to western and
southern Greenland and Davis Straits, though they are
apparently far more numerous to the north of this range.
They appear in Davis Straits in spring and summer and leave
that area in autumn, sometimes as late as November, to move
southward. They winter as far south as Cape Cod, where they
are the common dolphin species in April, May, and June
(sometimes to July). Their migrations are poorly known.
Stranded Specimens
Stranded white-beaked dolphins can be most readily
distinguished from white-sided dolphins by the substantial
differences in coloration and the differences in numbers of
teeth.
| White-Beaked Dolphin |
Atlantic White-Sided Dolphin |
| TEETH |
| 22-28 per side per jaw. |
30-40 per side per jaw,
sometimes more in upper
jaw. |
| COLORATION |
| Beak sometimes gray or
white above and below; two
pale areas visible on living
animals not visible on stranded
specimens. |
Beak all black; side marked
with elongated areas of
white with streaking patterns
of yellow and tan. |
Additional characteristics by which the two species may
be distinguished are summarized on p. 123.
Figure 140.—Two views of white-beaked dolphins off Newfoundland. This species is characterized by a prominent uniform dark gray dorsal fin and two
areas of paleness on the sides, one in front of and one below and behind the dorsal fin. White-beaked dolphins are distributed from Newfoundland north,
extending to more northerly waters than Atlantic white-sided dolphins. (Photos by H. E. Winn [bottom] and W. A. Watkins [top].)
Figure 141.—White-beaked dolphins reach nearly 10 feet (3.1 m) in length. Stranded animals, such as this specimen from Scotland, should be
distinguishable from Atlantic white-sided dolphins by their differences in coloration. This species sometimes has a white beak and always lacks the
elongated white patch and tan or yellow streaking found on the side of Atlantic white-sided dolphins. (Photos by A. S. Clarke.)
Other Common Names
Bottlenosed porpoise, gray porpoise, common porpoise.[12]
Description
Atlantic bottlenosed dolphins reach a maximum overall
length of about 12 feet (3.7 m) and weigh in excess of 1,430
pounds (650 kg). They have relatively stubby snouts and
dorsal fins, which are broad at the base, tall, and falcate.
Coloration varies slightly, but individuals are usually dark
gray on the back, lighter gray on the side, grading to white or
pink on the belly. Old females may have spots on the belly.
The dark coloration of the back often appears as a highly
distinct cape, particularly on the head.
Natural History Notes
Atlantic bottlenosed dolphins often occur in groups of up
to several hundred individuals which usually consist of
aggregations of small groups of no more than a dozen animals
each. They frequently associate with the Atlantic pilot
whales and are frequently found accompanying the right and
humpback whales travelling along the Atlantic coast of
Florida.
Atlantic bottlenosed dolphins have catholic tastes,
feeding on shrimp, eels, catfish, menhadden mullet, and
miscellaneous trash fish, to mention only a few. They are
frequently found near shrimp boats, feeding on fish stirred up
by the trawls or on discarded trash fish.
They sometimes move in to ride the bow wave of a vessel,
turning on their sides, sometimes spinning completely
around on their longitudinal axis when doing so. Individuals
may also turn their heads downward or to the side. They are
often found close to shore, in bays and lagoons, and
sometimes venture up the larger rivers. Some individuals,
especially the larger animals, are found as far offshore as the
edge of the continental shelf. Atlantic bottlenosed dolphins
sometimes ride the surf. Individuals may jump clear of the
water as high as 15-20 feet (4.6-6.1 m), a behavior on which
aquarium shows have capitalized.
Members of this species are the dolphins most commonly
maintained in captivity at zoos, aquariums, marine parks,
and research institutions. For that reason, they are perhaps
more familiar to the general public than any other species of
porpoise, dolphin, or whale.
May Be Confused With
From at least Cape Hatteras southward, the range of the
Atlantic bottlenosed dolphins distributed in inshore areas
may overlap with that of Atlantic spotted dolphins,
particularly during the spring and summer, when the
Atlantic spotted dolphins move inshore. There the two
species may be confused. The Atlantic bottlenosed dolphins
and the Atlantic spotted dolphins can be distinguished,
however, by the following characteristics:
| Atlantic Bottlenosed Dolphin |
Atlantic Spotted Dolphin |
| MAXIMUM SIZE |
| 8 feet to as much as 12 feet
(2.4 to 3.7 m). |
7.5-8 feet (2.3-2.4 m). |
| COLORATION |
| Not spotted (old females may
have spots on belly); dark
gray on back; light gray on
sides; white or pink on belly. |
Dark purplish gray on back;
lighter gray on sides and
belly; body becomes increasingly
spotted with age. |
| HEAD AND BEAK |
| Head robust; beak relatively
short. |
Head more slender; beak
longer. |
Some Atlantic bottlenosed dolphins are distributed well
offshore as far as the edge of the continental shelf. Those
individuals may be confused with either rough-toothed
dolphins (p. 135) or with grampus (p. 96). They may be
distinguished from rough-toothed dolphins by the following:
| Atlantic Bottlenosed Dolphin |
Rough-Toothed Dolphin |
| BODY COLOR |
| Dark gray on back; light
gray on side; white or pink on
belly. |
Dark gray, almost purplish
with yellow spots; lighter on
belly. |
| SNOUT |
| Relatively short and stubby,
and clearly demarcated from
forehead; usually all gray;
some older individuals have
white-tipped snouts and/or
white lips. |
Long and slender; not
clearly demarcated from
forehead; lower jaw and lips
speckled white. |
Distinguishing differences between the Atlantic bottlenosed
dolphins in offshore areas and grampus are tabularized
on p. 96.
In northeastern South America the range of the Atlantic
bottlenosed dolphin apparently overlaps with that of the
Guiana dolphin, which, except for size, it closely resembles
(see p. 132).
Distribution
The Atlantic bottlenosed dolphins are widely distributed
in the temperate and tropical waters of the western North
best known from New England southward to Florida,
westward in the Gulf of Mexico, and thence throughout the
West Indies and Caribbean to Venezuela.
In the northern portion of that range, Atlantic
bottlenosed dolphins are distributed offshore. In the
southern portions of their range from at least North Carolina
southward, the majority are found nearshore and often enter
bays and lagoons, and sometimes venture up the larger
rivers. Daily migrations in these areas may follow tidal flow.
In these same southerly areas some Atlantic bottlenosed
dolphins are distributed as far offshore as the edge of the
continental shelf.
Stranded Specimens
Within their range, stranded Atlantic bottlenosed
dolphins should be readily identifiable by 1) the robust body,
2) relatively short beak, and 3) the 20-26 teeth in each upper
jaw and 18-24 in each lower jaw.
Figure 142.—Atlantic bottlenosed dolphins leaping on the bow of a research vessel between Cape Cod, Mass. and Nova Scotia. Note the
robust body, the falcate dorsal fin, and the gradation of color in three zones—dark gray on the back, to lighter gray on the sides, to white or
pink on the belly. (Photo by A. Taruski.)
Figure 143.—A side view of the Atlantic bottlenosed dolphins off St. Augustine, Fla. Note the dark grayish coloration of the back, the lighter
coloration of the side, and the tall, sharply angled dorsal fin, pointed on the tip. Though dorsal fin shapes are highly variable, dorsal fins of
the Atlantic bottlenosed dolphin are usually more falcate and less pointed on the tip than on these animals. (Photo courtesy of Marineland
of Florida.)
Figure 144.—Atlantic bottlenosed dolphins frequently ride the bow wave, often turning on their sides as they do so. Note the distinctive color zones, the characteristic shape of the head and beak,
and the smooth lines of the flippers. (Photo by L. Rigley.)
Figure 145.—An Atlantic bottlenosed dolphin taken at Isla La Blanquilla, off Venezuela. Because they inhabit shallow waters, Atlantic bottlenosed
dolphins are infrequent victims of strandings. (Photo courtesy of F. Cervigon.)
Figure 146.—Atlantic bottlenosed dolphins have from
20 to 26 teeth in each side of the upper jaw and from 18
to 24 in each side of the lower jaw. These teeth, sharply
pointed in younger animals, may wear substantially as
the animal ages. (Photo courtesy of Wometco Miami
Seaquarium.)
Other Common Names
None known.
Description
Guiana dolphins are the second smallest cetacean species
in the western North Atlantic, reaching a maximum length of
only about 5.6 feet (1.7 m).
Their body shape is very similar to that of the Atlantic
bottlenosed dolphin, though the beak is less clearly
demarcated from the forehead.
The rather prominent dorsal fin is nearly triangular,
curving only slightly backwards near the tip.
Guiana dolphins are steel blue to dark brown on the back
and white on the belly. There is sometimes a brownish band
extending from the dark color of the back in front of the dorsal
fin back towards but not reaching the anus.
Natural History Notes
Guiana dolphins are usually found in groups of fewer than
10 individuals.
May Be Confused With
Because of their limited range and specialized habitats,
Guiana dolphins are unlikely to be confused with any other
cetacean species except perhaps Atlantic bottlenosed
dolphins (p. 128). These two species can be distinguished by
the following characteristics:
| Guiana Dolphins |
Atlantic Bottlenosed Dolphins |
| SIZE |
| To only 5.6 feet (1.7 m). |
8 to as much as 12 feet
(2.4 to 3.7 m). |
| DORSAL FIN |
| More nearly triangular; curved
only slightly backwards
near tip. |
Broad-based, tall, and
falcate. |
| DISTRIBUTION |
| Found in rivers and estuaries,
extend into only very
shallow nearshore waters on
limited area of South American
coast. |
Sometimes found nearshore
and in bays, river mouths,
and estuaries, but extend
farther offshore. |
Distribution
Guiana dolphins are found in Lake Maracaibo, in the
rivers of Guyana, and in the nearshore coastal waters of the
northeastern portion of the Guianas.
Stranded Specimens
In their very limited range, stranded Guiana dolphins can
be readily identified by their extremely small size (to 5.6 feet
[1.7 m]) and nearly triangular dorsal fin. Furthermore, in
addition to the characteristics listed above distinguishing
living Guiana dolphins from Atlantic bottlenosed dolphins,
the species can be distinguished by differences in the
numbers of teeth:
| Atlantic Bottlenosed Dolphins |
Guiana Dolphins |
| TEETH |
| 20-26 in each upper jaw;
18-26 in each lower jaw. |
26-35 in each jaw; often
ragged in arrangement. |
Figure 147.—A Guiana dolphin from Kartabo, British Guiana. In the coastal portion
of its range along the northeastern South American coast, this species is most likely
to be confused with the Atlantic bottlenosed dolphin. Guiana dolphins are much
smaller, rarely exceeding 5.6 feet (1.7 m), have a more triangular dorsal fin, and
tend to be found more frequently in estuaries and rivers. (Photo by A. B. Van
Beneden from Zoologica VII(4), by permission of the New York Zoological Society.)
Figure 148.—Guiana dolphins harpooned in Kartabo, British Guiana. Guiana dolphins have from 26 to 35 teeth in each jaw. Atlantic
bottlenosed dolphins, which are larger but somewhat similar in appearance, have from 20 to 26 teeth in each upper jaw and from 18 to 26
in each lower jaw. (Photo by A. B. Van Beneden from Zoologica VII (4), by permission of the New York Zoological Society.)
Other Common Names
Rough-toothed porpoise, goggle-eyed porpoise.
Description
Rough-toothed dolphins reach a length of at least 8 feet
(2.4 m). The coloration of the rough-toothed dolphins is quite
variable. Individuals are often dark gray to dark purplish
gray on the back with pinkish-white blotches on the sides
and belly. The flippers and flukes are dark and the belly is
white. Individuals are frequently scarred with numerous
white streaks.
The most distinctive characteristic of the rough-toothed
dolphin is its beak, which is quite long and slender, may be
white or pinkish white along both sides, including one or both
lips and the tip of the snout, and is not separated from the
forehead by the transverse groove present in other long-snouted
dolphins. Because the forehead and the sides of the
head slope smoothly into the rostrum, when this animal is
seen from above or from the side, its entire head appears very
long and nearly conical.
Natural History Notes
Rough-toothed dolphins occur in small groups of 50
animals or fewer and are usually found off the edge of the
continental slope. They may ride the bow waves.
May Be Confused With
In their offshore habitat, rough-toothed dolphins are most
likely to be confused with Atlantic spotted dolphins (p. 104)
and with Atlantic bottlenosed dolphins (p. 128). They may
be distinguished from Atlantic spotted dolphins by the
following:
| Rough-Toothed Dolphin |
Atlantic Spotted Dolphin |
| SNOUTS |
| Long and slender; not clearly
demarcated from forehead. |
Moderate in length and
clearly demarcated from
forehead. |
They may be distinguished from Atlantic bottlenosed
dolphins by the characteristics tabularized on p. 128.
Even at a distance the blotched coloration of the side and
the white coloration of the rostrum of rough-toothed dolphins
may be visible. If closer examination is possible, the
distinctive shape and coloration of the beak make positive
identification easy.
Distribution
Though records of rough-toothed dolphins from the
western North Atlantic are scant, the species is assumed to
be widely distributed in deep tropical to warm temperate
waters. It has been reported from Virginia, Georgia, Florida,
the Gulf of Mexico, the West Indies, and off the northeastern
coast of South America.
Stranded Specimens
In addition to the characteristics listed above for
distinguishing living animals, stranded rough-toothed
dolphins can be readily identified by the fact that the 20-27
fairly large teeth per jaw per side have a series of fine vertical
wrinkles on the crown, a characteristic from which the
species derives its common name. (These wrinkles are often
difficult to detect.)
Figure 149.—Captive rough-toothed dolphins in Japan. Note the distinctive, smoothly tapering head and the white
coloration of the sides and front of the snout. Rough-toothed dolphins are probably widely distributed in the offshore
waters of the tropics. The streamers on the backs of the animals are marker tags (see Appendix A.) (Photo courtesy of
Japanese Whales Research Institute.)
Figure 150.—Closeups of the highly distinctive head of a
rough-toothed dolphin showing the white lips and the lack
of a clear demarcation between the snout and the forehead.
This species has from 20 to 27 fairly large teeth in each side
of both the upper and lower jaws. (Photos at Sea Life
Park, Hawaii, by K. C. Balcomb [top] and S. Leatherwood
[bottom].)
Figure 151.—A rough-toothed dolphin stranded near New Smyrna Beach, Fla. This species has from 20 to 27 fairly large teeth in each side of both the upper
and lower jaws. Those teeth are sometimes marked by many fine vertical wrinkles along the crown, a characteristic from which the species derives its
common name. (Photos by D. K. Caldwell.)
Other Common Names
Slender blackfish, slender pilot whale.
Description
Pygmy killer whales reach a length of about 8-9 feet
(2.4-2.7 m). They are usually relatively slender-bodied with a
rounded head, an underslung jaw, and no beak.
The falcate dorsal fin, located about the center of the back,
is usually between 8 and 12 inches (20.3 and 30.1 cm) tall
(though it may reach 15 inches [38 cm] in some individuals), is
sometimes very distinctive, and resembles that of the
Atlantic bottlenosed dolphin. The flippers are slightly
rounded on the tips.
The color has been described as dark gray or black on the
back, often lighter on the sides, extending higher in front of
the dorsal fin and with a small zone of white on the
underside, often a lighter gray area on the sides, and
distinctive white regions around the lips. The chin may be
completely white. This white zone on the chin, described as
a "goatee," is often clearly visible in swimming animals.
May Be Confused With
The pygmy killer whale resembles the false killer whale
but is much smaller and can be distinguished at close range by
the zones of white coloration. False killer whales are almost
all black and reach a length of up to at least 18 feet (5.5 m).
Pygmy killer whales are dark gray on the back, often lighter
on the sides, and show a region of white on the belly which
may extend so high up onto the sides that it is visible on a
swimming animal. Further, they reach only 8-9 feet (2.4-2.7
m).
Pygmy killer whales may also be confused with the
similarly sized and colored many-toothed blackfish. So little is
known of the two species' appearance and behavior at sea that
it is doubtful that they can be successfully distinguished,
though many-toothed blackfish apparently lack the white
region often seen on the sides of pygmy killer whales.
Further, pygmy killer whales have rounded flippers and
smoothly tapered heads, while those of the many-toothed
blackfish are pointed on the tip and more sharply pointed
(often described as a parrot beak).
Distribution
Pygmy killer whales are probably distributed in the
tropical and subtropical waters of the western North
Atlantic. They have been reported from Texas, the Atlantic
coast of Florida, and St. Vincent Island, Lesser Antilles.
Records of the species from the other oceans of the world
suggest that its distribution is limited to tropical and
subtropical waters.
Stranded Specimens
Stranded pygmy killer whales can be clearly distinguished
from both the false killer whale and the many-toothed
blackfish. In addition to the differences discussed above, the
following are key differences between the pygmy and false
killer whales:
| Pygmy Killer Whale |
False Killer Whale |
| TEETH |
| 10-13 in each side of upper
and lower jaws; lower teeth
smaller. |
8-11 per jaw per side,
prominent. |
| VENTRAL COLORATION |
| White from anus to under tail
stock, white may extend up
sides. |
Dark from anus to tail stock;
lighter pale gray area forward
between flippers. |
| FLIPPERS |
| Smoothly rounded. |
Characteristic hump on forward
margin. |
Pygmy killer whales can be distinguished from many-toothed
blackfish on the basis of the second species' larger
number of teeth. (Many-toothed blackfish have from 22 to 25
teeth in the upper jaw and from 21 to 24 in the lower jaw.)
Figure 152.—Pygmy killer whales at sea northwest of Hawaii (top) off the island of
Oahu, Hawaii (middle), and from southeastern Florida in the tank at the Wometco
Miami Seaquarium (bottom). When swimming rapidly, pygmy killer whales may
closely resemble the much larger false killer whales. In addition to their much smaller
size, rarely exceeding 9 feet (2.7 m), however, pygmy killer whales can be
distinguished by their more rounded head, the white coloration of the lips and chin, and
the white zone on the belly, sometimes extending up the sides. (Photos by S. Ohsumi
[top]; J. Naughton, National Marine Fisheries Service and courtesy of E. Shallenberger,
Sea Life Park [middle]; and courtesy of Wometco Miami Seaquarium [bottom].)
Figure 153.—Pygmy killer whales 5 miles off Kaena Point, Oahu, Hawaii. These individuals were dark on the back with varying degrees of lighter
coloration on the sides, extending high onto the sides in front of the dorsal fin. Many had a white "goatee" on the chin and lower jaw. The prominent dorsal
fin is characteristic. (Photos by E. Shallenberger, courtesy of Sea Life Park, Hawaii.)
Figure 154.—Side and belly views of a pygmy killer whale from South Africa. Note the slight white coloration of the lips, the white region on the
ventral surface (extending up onto the sides just below the dorsal fin), and the falcate sharply pointed dorsal fin. Note also the flippers, which
lack the hump on the forward margin characteristic of false killer whales. (Photos courtesy of P. B. Best.)
Figure 155.—Pygmy killer whales have from 8 to 11 teeth in each side of
the upper jaw and from 11 to 13 in each side of the lower jaw. Many
specimens reportedly have one fewer on the right than on the left side.
The teeth are smaller than those of the false killer whale and far less
numerous than those of the more closely sized many-toothed blackfish.
Note also the white lips. (Photo courtesy of P. B. Best)
Other Common Names
Hawaiian blackfish, melon-headed whale.
Description
Many-toothed blackfish reach lengths of at least 9 feet (2.7
m) and are similar in body shape to the larger false killer
whale and the similar-sized pygmy killer whale. The body is
elongated and slim with a rather slim tail stock. In general,
the head is shaped like that of the false killer whale but has a
sharper appearance to the snout, sometimes described as
a parrot-beak. The forehead is rounded, slightly overhanging
the lower jaw, and has no beak. The dorsal fin is up to 10
inches (25.4 cm). It is probably very distinctive as the animals
surface to breathe. Many-toothed blackfish are black on the
back and slightly lighter on the belly. The areas around the
anus and genitals and the lips are unpigmented. Many-toothed
blackfish are presumably rare.
May Be Confused With
Many-toothed blackfish may be confused with either the
false killer whale or the pygmy killer whale. They are
considerably smaller than the false killer whale, have a
slightly more pointed snout, and lack the prominent humplike
forward margin on the flippers which is characteristic of the
false killer whale.
They are approximately the same size as pygmy killer
whales, but the white area around the genitals which extends
up onto the side in pygmy killer whales may be lacking in
many-toothed blackfish. This species has pointed flippers,
while those of pygmy killer whales are rounded on the tips.
Many-toothed blackfish also have a slightly more pointed
snout. Otherwise, the two species are virtually indistinguishable
in encounters at sea.
Distribution
Although many-toothed blackfish have not yet been
reported in the western North Atlantic, they are included
in this guide because of a record from the eastern tropical
North Atlantic and the known tropical distribution in
other areas.
Stranded Specimens
Stranded many-toothed blackfish can be distinguished
from false killer and pygmy killer whales by the number of
teeth alone. Many-toothed blackfish have more than 15 per
side per jaw (usually 21-25); both other species have
less than 15.
Figure 156.—A live many-toothed blackfish in a holding pen
in the Philippines. At sea these animals will be virtually
impossible to distinguish from pygmy killer whales. (Photos
by T. Hammond.)
Figure 157.—A many-toothed blackfish stranded in Hawaii. This species is smaller than the false killer whale and can be positively identified by the number of teeth, larger than any other
blackfish. Many-toothed blackfish have from 21 to 25 teeth per side in both the upper and lower jaws. Other blackfish species have fewer than 15; otherwise, with the exception of differences in
flipper shape (those of this species are pointed while those of pygmy killer whales are rounded on the tip), coloration and body shape of the two species are similar. (Photo courtesy of T. Dohl.)
Other Common Names
None known.
Description
Pygmy sperm whales reach a length of at least 11 feet (3.4
m). They are characterized by 1) an extremely robust body
that rapidly tapers near the tail, 2) a squarish head, and 3) a
narrow, underslung lower jaw which is located well behind
the tip of the snout. Along the side of the head, in
approximately the same position where gill slits would be
located on a fish of comparable size, there is a crescent-shaped
bracket mark, often called a false gill.
The flippers, which are smoothly curved on the forward
margin and may reach a length of 18 inches (45.7 cm) or more
on an adult specimen, are located well forward on the body,
just below and behind the bracket mark.
The dorsal fin is very small, falcate, and located in the
latter half of the back.
Though coloration can be described only from stranded
specimens and a few encounters with living animals, pygmy
sperm whales appear to be dark steel gray on the back,
shading to a lighter gray on the sides, and gradually fading to
a dull white on the belly. The outer surface of the flippers and
the upper surface of the tail flukes are also steel gray.
Natural History Notes
From the few accounts, the following may be summarized
about the behavior of pygmy sperm whales at sea: They
reportedly usually rise slowly to the surface to breathe,
produce a blow that is inconspicuous, and do not normally roll
aggressively at the surface like most other species of small
whales. They reportedly fold their flippers flat against their
bodies when swimming. They have been reported to lie
motionless in the water with the back of the head on the
surface and the tail hanging loosely down in the water. (A
similar behavior in sperm whales has made them a minor
hazard to shipping, since it has resulted in some collisions
with ships.) When they are startled in this posture, they may
defecate, issuing a cloud of reddish brown to rust-colored
fece. Beached pygmy sperm whales have also been observed
to defecate a fine chocolate feces.
Pygmy sperm whales apparently feed primarily on squid,
but do take fish as well.
May Be Confused With
In general, when they can be examined at close range,
pygmy sperm whales are so distinctive that they are unlikely
to be confused with any other species except perhaps the
dwarf sperm whales. At a distance, they might be confused
with small individuals of any of the beaked-whale species
(p. 78) that also have a relatively small, falcate dorsal fin
located in the latter third of the back. Closer examination
should permit easy separation, however, since the pygmy
sperm whale has a blunted head, while the beaked whales, as
the name implies, have elongated "dolphinlike" beaks and are
considerably larger. At sea, pygmy sperm whales are most
likely to be confused with their cousins the dwarf sperm
whales (p. 148 and Fig. 160). The two species can be distinguished
as follows:
| Pygmy Sperm Whale |
Dwarf Sperm Whale |
| MAXIMUM SIZE |
| To 11 feet (3.4 m). |
To 9 feet (2.7 m). |
| DORSAL FIN |
| Small to 8 inches (20.3 cm),
falcate; located in latter third
of back. |
Taller, more like that of
bottlenosed dolphins; located
near the midpoint of the
back. |
| COLORATION |
| Both species are dark steel gray on the back, grading to
lighter on the belly. |
Distribution
Because they have been rarely observed at sea, normal
ranges for this species are not known. Based on stranding
records, however, the following can be stated. In the western
North Atlantic, pygmy sperm whales have been found as far
north as Sable Island, Halifax, Nova Scotia, as far south as
Cuba, and as far west as Texas in the Gulf of Mexico. They are
frequently found stranded along the Atlantic coast of Florida
and throughout the eastern and northern Gulf of Mexico.
Stranded Specimens
Because of the distinctive characters of the genus,
stranded pygmy and dwarf sperm whales are unlikely to be
confused with any other species of cetacean, though the
rather narrow underslung jaw and the blunted head may
result in their casual dismissal by some beach walkers as
stranded sharks. The two species of Kogia may be
distinguished by the following:
| Pygmy Sperm Whale |
Dwarf Sperm Whale |
| TEETH |
| 12-16 (rarely 10-11) in lower
jaw are larger; no teeth in
upper. |
8-11 (rarely 13) small and
extremely sharp teeth in
lower jaw; sometimes have
up to 3 teeth in each upper
jaw. |
| THROAT |
| No creases or grooves on
throat. |
Several short irregular creases
or grooves on throat. |
Figure 158.—In this rare photograph of a pygmy sperm whale at sea in the Pacific, the animal
was startled by the approaching vessel, circled quickly, and then dived out of sight. The trail
of material visible in the water in front of and to the right of the animal is feces, reddish brown
to rust in color. Startled whales and porpoises often defecate in this manner. (Photo by S.
Ohsumi.)
Figure 159.—A young pygmy sperm whale swimming in a tank at the New York Aquarium. Note the shape and position of the dorsal fin and the shape of the
head. (Photo by H. E. Winn.)
Figure 160.—On the beach the two species of Kogia can be readily distinguished. The pygmy sperm whale, K. breviceps, (top) reaches a length of about
11 feet (3.4 m); its dorsal fin is a small nubbin located in the latter half of the back. The dwarf sperm whale, K. simus, (bottom) reaches only about 9 feet
(2.7 m); its dorsal fin, much taller and more "dolphinlike" in appearance, is located near the middle of the back. Coloration of fresh specimens is probably
similar for both species—the lightened areas in the lower photograph are the result of decomposition. (Photos from Jekyll Island, Ga. [top] and Atlantic
Beach, Fla. [bottom] by D. K. Caldwell.)
Figure 161.—Ventral view of a female pygmy sperm whale from Jekyll Island, Ga. Note the position and shape of the flippers and mouth, and the abrupt
tapering of the body at the tail stock. (Photo by D. K. Caldwell.)
Figure 162.—Head of a pygmy sperm whale from northeastern Florida showing gill-like, lightly
pigmented "bracket marks." (Photo by F. G. Wood.)
Figure 163.—A detailed view of the mouth of a pygmy sperm whale from
the east coast of Florida. In both species of Kogia these long, curved,
needle-sharp teeth, found in only the lower jaw, lock into sockets in the
upper jaw. Pygmy sperm whales have from 12 to 16 (rarely 10 or 11) pairs
of teeth; dwarf sperm whales have from 8 to 11 (rarely 13) pairs. (Photo
by D. K. Caldwell.)
Other Common Names
Rat porpoise (West Indies).
Description
Dwarf sperm whales reach an overall length of
approximately 9 feet (2.7 m). Like the other species of Kogia,
the pygmy sperm whale (p. 144), the dwarf sperm whales are
characterized by 1) a squarish head, 2) an extremely robust
body which tapers rapidly near the tail stock, 3) a narrow,
underslung lower jaw, and 4) a bracket mark or false gill on
the side of the head.
The dorsal fin of this species is tall and falcate, closely
resembling that of the Atlantic bottlenosed dolphin, and is
located near the midpoint of the back. There are several
short, irregular creases or grooves on the throat similar to
those found on the sperm whale (see Figs. 60, 165).
Dwarf sperm whales are dark steel gray on the back,
grading to lighter gray on the sides, and fading to dull white
on the belly.
May Be Confused With
Because of their tall, falcate dorsal fin, dwarf sperm
whales may be confused at a distance with any of the small
dolphin species. Their all-black or dark steel-gray coloration
and the blunted head increase the likelihood that they can be
confused with pygmy killer whales or many-toothed
blackfish. They will have to be examined at close range before
they can be distinguished.
Dwarf sperm whales may also be confused with pygmy
sperm whales (p. 144 and Fig. 160). The two species can
be differentiated by the characteristics tabularized on p. 144.
Distribution
Since it has only recently been recognized as a species
distinct from the pygmy sperm whale and even more recently
given a common name, records of dwarf sperm whales may
have been confused with those of its close relatives. The
dwarf sperm whale has been reported from at least Georgia
south to St. Vincent, Lesser Antilles, and throughout the
eastern and northern Gulf of Mexico. It is highly likely that
this species, like the pygmy sperm whale, extends further to
the north.
Stranded Specimens
Because of the distinctive characteristics of the genus,
neither species of stranded Kogia is likely to be confused with
any other species. They can be distinguished from one
another by the characteristics tabularized on p. 144.
Figure 164.—A dwarf sperm whale stranded near St. Augustine, Fla., shown swimming in the tank at Marineland of Florida. In this species
the dorsal fin is taller than that of the pygmy sperm whale and is located near the midpoint of the back (see Figs. 159 and 160).
(Photo courtesy of Marineland of Florida.)
Figure 165.—Dwarf sperm whales have several
short creases on the throat, similar to those
found on the sperm whale (see Fig. 60); pygmy
sperm whales lack these creases. To compare
other features of the two species, refer back to
Figure 160. (Photo by D. K. Caldwell.)
Figure 166.—Closeup of the tail flukes of a
dwarf sperm whale from the Florida east coast.
Note that the dorsal ridge extends almost to
the notch in the flukes. (Photo by W. A. Huck,
courtesy of Marineland of Florida.)
Other Common Names
Common porpoise, herring hog, puffing pig (Newfoundland
and New England), Pourcils (Quebec), harbour porpoise.
Description
The harbor porpoise is the smallest cetacean species in the
western North Atlantic Ocean, reaching a maximum overall
length of about 5 feet (1.5 m). Its most distinctive identifying
features in encounters at sea are 1) the small, chunky body; 2)
the coloration, dark brown or gray on the back, fading to
lighter grayish brown on the sides, often with speckling in the
transition zone, and white on the belly extending farther up
on the sides in front of the dorsal fin; 3) the small rounded
head, lacking a distinctive beak; 4) the small, triangular
dorsal fin; and 5) the shallow, inshore northerly
distribution.
Natural History Notes
As the name implies, the harbor porpoise inhabits bays,
harbors, river mouths, and all the relatively shallow inshore
water between. Though it may travel in schools of nearly a
hundred individuals, it is more often seen in pairs or in small
groups of from 5 to 10 individuals. It often swims quietly at
the surface. It will not ride the bow wave and is very difficult
to approach closely by boat.
May Be Confused With
The harbor porpoise is not known to associate with
dolphins but is sometimes seen in close proximity to fin
whales and humpback whales off the Canadian coast in spring
and summer. Because of its northern inshore habitat, the
harbor porpoise is not likely to be confused with any other
cetacean.
Distribution
Harbor porpoises are restricted to the colder waters of the
western North Atlantic Ocean. They have been reported
from North Carolina north to the Davis Straits and the waters
of southwestern Greenland. Within this range they are
probably most common in the Bay of Fundy and off southwest
Greenland.
Stranded Specimens
In addition to the characteristics described above for
living animals, stranded harbor porpoises can be readily
identified by the small spade-shaped teeth, 22-28 per jaw.
Figure 167.—Two views of a harbor porpoise just offshore from Rio del Mar, Seaside, Calif. Note the small size (usually less than 5 feet [1.5 m]), the small
triangular dorsal fin, the dark brownish color of the back, and the lighter color of the sides and belly intruding higher up in front of the dorsal fin. Harbor
porpoises frequent inshore areas, shallow bays, estuaries and harbors, and reportedly do not approach moving vessels nor ride bow waves. (Photos by J.
D. Hall.)
Figure 168.—A harbor porpoise harpooned in Passamaquoddy Bay, New Brunswick. Harbor porpoises have from 23 to 28 small, spade-shaped teeth
in each upper jaw and from 22 to 26 in each lower jaw. Note the rounded head, the absence of a beak, and the triangular dorsal fin. (Photo by D. E.
Gaskin.)
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