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Humpback
Whale
The
Humpback whale is known for its spectacular breaching,
flipper-slapping and tail-slapping. It is easily identified at
close range by its knobby head and long flippers. The black and
white coloration on the underside of the flukes (tail) allows
scientists to distinguish and name individuals all around the
world. No two Humpback whales are exactly alike.
During breeding season the Humpback males are
known for singing the longest and most complex songs in the animal
kingdom. Humpbacks are highly inquisitive and will approach quite
closely, showing little fear of boats.
The Humpback whale has a more robust body than
other similar whales. It's back and flanks are grey or black with
an area of white on the throat and belly. It has a slender head
which constitutes up to one-third of its total body length. The
top of the head is flattened and covered by a number of fleshy
knobs or tubercles. The lower jaw has a rounded protuberance near
the tip and is covered with similar tubercles to those on the
head. Baleen plates numbering between 270 to 400 are found on each
side of the upper jaw. The plates are relatively short and black
or dark grey.
The Humpback has exceptionally long flippers
with knobs along the leading edges. While the underside of the
flipper is usually white geographical differences have altered the
upper side. On the flipper of Pacific Humpback the upper side is
usually black whereas in populations of the Atlantic Humpback the
upper side is mostly white with black markings.
Blue Whale
The
Blue whale is, and always has been, the largest animal ever to
exist on earth. This whale can grow to a length of 110ft and weigh
190 tons but on the average it is much smaller. The Blue whale is
called a "rorqual" a Norwegian word for "furrow" and refers to the
pleated grooves running from its chin to its navel. The throat
grooves, in addition to streamlining the shape of the whale, allow
the throat area to expand tremendously during feeding, and can
hold 1,000 tons or more of food and water when fully expanded. By
taking tons of water into its mouth and filtering out the fish or
krill with its baleen plates a medium-sized Blue whale can eat
over 4 tons of krill a day.
Gray
Whale
The Gray Whale is one
of the most active of all large whales with spy-hopping,
tail-slapping and breaching commonly observed. The Gray can grow
to a length and weight of 50ft and 35 tons for the female and 46ft
and 16 tons for the male. This whale is well known for the 12,000
mile round trip between its northern feeding grounds in the
Beaufort, Bering and Chukchi seas and its southern breeding
grounds in Baja California and off the Korean coast. Primarily a
bottom feeder, the Gray will dive to 400ft deep, but prefers much
shallower water.
The Gray whale
is mottled grey over it's entire body including the flippers and
tail flukes (though albino individuals are not uncommon). This
grey body is covered with white, yellow or orange patches of
barnacles and associated parasites (whale lice), particularly on
top of the head, around the blowhole and on the anterior part of
the back. The head is narrow and arched along the upper surface
giving it a conical shape. It's mouth contains small hairs along
the upper jaw with 130-180 relatively small baleen plates on each
side.
Sperm
Whale
The
Sperm whale is the largest of all the toothed cetaceans and has
the largest brain of any animal upon earth. Named Sperm whale for
the spermaceti oil found in its head, this whale was heavily
hunted particularly for its oil. Before the advent of synthetic
oils, the spermaceti oil was the finest oil known for running
machinery.
The Sperm whale, like the Gray whale, exhibited revenge when
hunted, and has destroyed small vessels killing many whalers. The
famed Moby Dick was a Sperm whale. Inhabiting every ocean in the
world, this species somehow survived the whaling days in fairly
large numbers and at present there may be between half a million
and a million sperm whales alive.
Sperm whales are very deep divers and can probably dive as deep as
10,000 feet, which is astonishing considering the fact that they
are air breathing mammals; the pressure alone at this depth is
unimaginable. They can remain submerged for over one hour. Here
they hunt giant squid, which seems to be their favorite food. They
emit a rapid series of clicks and noises that sound like gunshots,
the clicks become faster and faster as they home in on their prey.
Among this species, males are considerably larger than females,
the difference being 34-37 feet for females and 55-60 feet for
males. The Sperm whale, along with the dwarf and pygmy sperm
whales, are the only cetaceans to have their blowholes not in the
center on top of their heads, but displaced to the left side, so
that the spout is low and bushy and goes off to the left side of
its body. This allows for an easy field identification even from a
great distance, especially on calm days when a spout would
otherwise go straight upwards. Large males can weigh up to 50 tons
making them a very large and fierce predator. Adult Sperm whales
are an awesome sight. They will occasionally breach and also swim
close attempting to interact with boats. They often bring their
tails high out of the water while diving and the distinct shape of
each tail is the best type of individual identification available
to the researcher.
Orca
(Killer) Whale
The
Killer whale is the largest member of the dolphin family. This
distinctive jet-black, brilliant white and grey marked, huge
dorsal finned male, makes this animal relatively easy to identify.
The Orca can grow to a length of 23ft and weigh 4 tons in the male
and 21ft and 3.3 tons in the female.
Despite it's name, the Killer whale has never hurt a person in the
wild. It is inquisitive and approachable and aggression within a
pod is rare. The pod is a close-knit family group and is stable
from one generation to the next. It's members usually stay
together for life. When two or more pods come together temporarily
the group is called a "superpod" and may number more than 150
whales. Usually larger groups split up into two or more smaller
ones as the population grows. These groups of closely related pods
(clans) often develop their own dialects.
The head of the Killer whale is conical-shaped.
It has an indistinct beak with a conspicuous white oval patch
above and behind the eye. It's jaw is broad with relatively few
large conical teeth, 10-12 pairs in each jaw, and very powerful
muscles to the rear of the upper jaw. These aid the retainment of
large prey that would normally resist capture.
The Orca is a versatile predator and has one of
the most varied diets of all whales. Although it has been observed
feeding upon penguins, seals, porpoise and large baleen whales
it's reputation for doing so is probably exaggerated. For most
populations of Killer whales the diet appears to be primarily fish
such as salmon and cod, and squid. It's consumption of birds,
penguins, sea turtles, seals, and porpoise undoubtedly depends
upon local availability. |
