Connecting With Other Classrooms
To contribute to the discussions below send e-mail to: JN-Talk@Learner.org
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Teacher Connecting With Other Classrooms To contribute to the discussions below send e-mail to: JN-Talk@Learner.org
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The Humpback Whale
The humpback whale is probably the most common of the giant
baleen whales. It was also once the most endangered. The species
developed around 10 million years ago and because its ability to
change, it continued to grow.
Humpback whales are seen in coastal waters all over the world.
In the summer they feed on the polar regions. In the winter they breed
in the tropics, with the exception of those in the Arabian sea. These
whales appear to stay the whole year in the same place. There are
humpbacks in the north Atlantic, north Pacific, and some scattered
throughout the southern hemisphere.
For centuries the oceans have been used as universal dumping
grounds. It was thought that toxic-waste would be diluted and
dropped in the sea and never seen again. How wrong we were! First they are
taken by the plankton, which in turn are eaten by the small fish or shrimps.
these are engulfed in huge quantities by the giant whales. The
whales throughout their own lives have been storing substances in their
blubber and in their livers.
Baleen whales are some of the largest animals. Their large size
allows for protection from predators, and is an advantage in species
that compete for mates. On land, animals must support their weight.
In the aquatic environment water helps support an animals body
weight allowing for the potential for greater size. Large size allows whales
to take advantage of high food productivity and store that energy in the
form of blubber.
All baleen whales show some variation of a characteristic torpedo
shaped body shape. this body shape reduces drag and is energy
efficient for swimming.
Most baleen whales change skin color changes of black and gray.
Some species show some extent of countershading; the top surface is
darker than the bottom surface. This coloration typical of many
marine animals, provide camouflage. The results is that predators or prey do
not see a contrast between the countershaded animals and the
environment.
Each lobe of their tale is called a fluke. Flukes are flattened
pads of tough fibrous connective tissue, completely without bone or
muscle. Flukes are oriented horizontally. Longitudinal muscles of
the back and caudal penducle move the flukes up and down. Humpback
whales also have a small dorsal fin located on a hump. The shape of the
dorsal fin varies among the humpback whales.
Baleen whales have two blowholes located on the top of their
head. Blowholes are covered by muscular flaps. These flaps provide a water
tight seal. There is a "splash guard" in the front of the blowhole
region in some species. This prevent water from entering the
blowholes upon surfacing to breathe. Each blowhole leads to an air passage
that leads to baleen whale's trachea and then to its lungs.
Baleen whales have a smooth skin surface with no oil glands or
pores. Many species have several hairs located on the snout jaws and
chin.
By Margot Seidman
Mrs. Berger Class
Right Whales
Right whales have a thick and solid body and an unusually large
body. The head of most right whales makes up about a third of the
total body length. Right whales swim an average of 3 miles per hour.
They feed by swimming into a mass of plankton with their mouths
open. Water flows through the baleen, and the plankton becomes
entangled into the baleen fibers. There are three kinds of right
whales, the bowhead whale, the black right whale, and the pygmy
right whale.
The right whale got its name form the fact that it was the
"right" whale to hunt. This is because it had a large amount of
blubber and fat. It was so easy to hunt that it soon became so
common that whalers did not have to go after other preys.
It is estimated that when the pilgrims landed, in what it is
known as Plymouth, there were about 20,000 right whales in the
Atlantic Ocean. Now there are about 320-340 whales left in this
sector. Many people wonder if this specie will survive from a low
population and a weak genetic pool.
The right whale had no dorsal fins. It has extremely long
baleen plates, about 60 feet, in its arch upper jaw. It is hard to see in
the water because it moves slowly.
A striking feature of the right whale is its pattern of
callosities,
which are patches of thickened skin often colored by whole lice a
type of crustacean. These white patches are on its head, over its
eyes, and around its mouth., and are different in each whale. These
patches are used by scientists to identify individual whales. But
since a right whale doesn't often get much of its head out of the
water, it makes it hard for researchers to identify them.
right whales have their calves in the water off the coast of
Georgia and Florida. Many spend the spring in the waters around
Cape Cod, including the stellwagon bank area. In the summer
researchers believe most of the right whales congregate in waters in
and near Bay of Funky to breed. Although females and calves go to
the south during winter, it is nit know where young males and non-
pregnant females go during the winter. This is one of the many
unknown facts about the right whale's life.
By Tina Galani
Mrs Berger class
K12robzj@hofstra.edu or jberger@dorsai.org
Joan Berger
Internet Educational Consultant * * * * * * * * * * * * * * * *
Roslyn Public Schools * "...for the world is hollow *
Roslyn, NY 11577 * and I have touched the sky!"*
FAX (516)826-0358 * * * * * * * * * * * * * * * * *
**Visit the East Hills School WEB SITE at http://www.dorsai.org/~jberger/
© Journey North 1996