There are eight species of whales that frequent the cold and icy waters of
Alaska. The Beluga, Humpback, Grey, Orca,
Bowhead, Blue, Right, and Minke whales. Like all mammals, whales breathe air into lungs, are warm-blooded, breast-feed their young, and have some (although very little) hair. The whales' ancestors lived on land, and their adaptions to a fully aquatic life are quite striking. The body is fusiform, resembling the streamlined form of a fish. The forelimbs, also called flippers, are paddle-shaped. The end of the tail holds the fluke, or tail fins, which provide propulsion by vertical movement. Although whales generally do not possess hind limbs, some whales (such as sperm whales and baleen whales) sometimes have rudimentary hind limbs; some even with feet and digits. Most species of whale bear a fin on their backs known as a dorsal fin.
Beneath the skin lies a layer of fat, the blubber. It serves as an energy reservoir and also as insulation. Whales have a four-chambered heart. The neck vertebrae are fused in most whales, which provides stability during swimming at the expense of flexibility.
Whales breathe through blowholes, located on the top of the head so the animal can remain submerged. Baleen whales have two; toothed whales have one. The shapes of whales' spouts when exhaling after a dive, when seen from the right angle, differ between species. Whales have a unique respiratory system that lets them stay underwater for long periods of time without taking in oxygen. Some whales, such as the Sperm Whale, can stay underwater for up to two hours holding a single breath. The Blue Whale is the largest known animal that has ever lived, at up to 93ft long and 180 tons.
Their skin has evolved hydrophilic properties. Its surface is covered with microscopic pores surrounded by nanoridges. Between these ridges there is a rubber-like gel which is excreted from the gaps between the skin cells. This gel contains enzymes that attacks microbes, and the edge of the ridges makes it hard for smaller organisms to get attached.
Beluga
Whale:
Beluga whales are not born white. It takes about
6 years until they gradually turn white. Belugas
are one of the three whales that spend all their
lives in arctic waters. Beluga are special among
all whales because they can turn their heads.
Maybe this is so that they can communicate with
each other better! Beluga are very social and
make a wide variety of sounds.
Humpback
Whale:
Graceful and magnificent, humpback whales inspire
awe in young and old alike. These marine mammals
travel great distances to take advantage of the
best breeding grounds and feeding spots. North
Pacific humpbacks, for example, mate and give
birth in Hawaii and then travel to Alaska each
summer to feed.
Gray
Whale
Whalers used to call them "devilfish" because of
the fierce defense they put up when hunted. In
its lifetime, the average gray whale commutes
over 400,000 miles – the equivalent of a
trip to the moon and back. Each year, gray whales
go back and forth between their feeding grounds
in the Arctic to breeding grounds off the coast
of Baja California. They spend six months of the
year just traveling!
Orca - Killer Whale:
Killer whales are social animals that live in
stable family-related groups. Killer whales
display a high level of care for their offspring.
In addition to the mothers, various pod members
(mainly adolescent females) perform most of the
care for the calves. As with most mammals, killer
whales are very protective of their young. Killer
whales are often compared to wolves because both
species are top predators, maintain complex
social relationships, and hunt
cooperatively.
Bowhead
Whale:
Bowhead whales were hunted
by commercial whalers for over four centuries,
beginning in the North Atlantic in the 1500s and
ending in the North Pacific by the mid-1900s.
Bowhead whales are capable of breaking through
sea ice at least 8 inches thick; some Eskimo
hunters have reported whales surfacing through 2
feet of thick ice.
Blue Whale
:
Everything about the blue
whale is enormous. It is the largest animal on
earth, ever. A big blue whale can be 100 feet
long and weigh up to 150 tons. That's as large as
a Boeing jet. Its heart is as large as a small
car. Fifty people could stand on its tongue. Its
spout shoots up at least 30 feet when it surfaces
for air.
Right
Whale:
Right whales prefer
coastlines and sometimes large bays, but may
spend a lot of time on the open sea. The Northern
right whale populations are considered to be
close to extinction. Right whales are baleen
whales, they filter their food through their long
baleen plates. Right whales open their great
mouths and graze along the surface of the water.
Right whales mostly eat small crustaceans
including copepods and small shrimp-like animals
called euphausiids.
Minke Whale:
The minke is the smallest
of the baleen (filter-feeding) whales and is
found throughout the world's oceans, from the
Arctic to the Antarctic. This is an inquistive
cetacean and will frequently approach and linger
around ships. The natural life span of minke
whales is about fifty years.
Some information gathered
here from Discovery.com
