The Marine
Friends Project :: Life
in the Ocean ::
 More
Whale Facts
by Sallie K. Riggs
Are Whales Fish?
Whales are not fish? But how do you know? You can tell the difference
by watching the animal and asking yourself three questions:
Does its body move sideways or up and down when it swims?
Fish, including sharks, propel themselves through the water by
using their body muscles to push their tails side-to-side.
Whales and dolphins push their tails up and down. The dolphin's
body muscles can generate enough power to push it through the water
at speeds up to 20-30 miles per hour. That's faster than you ride
your bike, even at top speed.
Does it have gills or a nose?
Both fish and whales need oxygen. Fish use gills, open flaps along
the sides of their bodies, to take oxygen from the water. A whale
uses its nose and lungs, like you do. It's hard to see a whale's
nose. It doesn't stick out the way yours does because whales need
streamlined bodies to help them swim fast. And they need a nose
on the top of their head so they can breathe while the rest of their
bodies are in the water.
So when you're on a whale watch boat, look carefully. If you see
something with gills, it's a fish; If you see either one or two
holes on the top of the head, it's a whale and those are the "blowholes."
Does it have a baby swimming with it?
Fish lay eggs and then leave the baby fish to grow up on their
own. Whales and dolphins give birth to babies, just like people
do. And then they feed and care for their babies for several months,
sometimes even for several years. So now that you know the questions
to ask, you should be able to tell that a whale is not a fish.
How Do Whales Breathe?
Because whales live in the ocean, many people think they are fish.
But do you know that whales and dolphins are not fish? They are
mammals. People are mammals too. Mammals are the group of animals
that breath air using lungs, give birth to live young (rather than
laying eggs), and feed their young with mother's milk. All animals,
including people, need oxygen, a chemical found in the air and in
water. Fish use their gills to take oxygen from the water that they
live in. But people get the oxygen we need by breathing air, using
our lungs. Whales and dolphins use their lungs to breathe air also.
That's one reasons why they come to the surface of the ocean. Sometimes
they lie right at the surface of the water, with just a part of
their back sticking out. Look closely at a picture of a whale or
dolphin: can you see a nose on the whale? You can't, because whales
don't have noses like you and me. Instead they have a hole in the
flat part of the middle of their heads. Those holes are called "blow
holes." Sometimes when a whale breathes air out of its hole,
it shows up as a spray or mist - or a spout - that can be seen many
miles away. Blow holes are surrounded by muscles that keep the hole
closed when the whale or dolphin is under water and open it when
the animal is at the surface and needs to breathe.
In fact, some of the animals have two blow holes next to each other
and others have only one. So when you see a picture of a whale,
see if you can tell the difference. Pilot whales and dolphins have
one blow hole; humpbacks, minkes and right whales have two.
What is a Whale's Spout?
Is a whale's a fountain of water? Both wWhales and people use lungs
and noses to breathe air. But because whales live in the water their
noses and lungs work differently from yours. Whales don't breathe
as often as you do, only when they are on the surface of the ocean.
That means they , have to take in and let out a lot of air quickly.
Their lung muscles are strong enough to force almost all the air
out at once. One breath just about empties their lungs. In contrast,
But one of your breaths empties only part of your lungs. When a
whales comes to the surface after a dive, ithe breathes yleout the
"old" air quickly, all in one breath. Because the whale
empties its lungs with such force, the air travels a great distances
- 10, 20, even 40 feet. And because its nose is on the top of its
head, the air goes straight up. This air is usually warmer than
the air just above the surface of the ocean, so the water vapor
(small particles of water carried in the air) condenses.
This condensed water vapor looks like steam - the same thing happens
when you "see your breath" on a cold winter day. So the
"spout" you see is not a fountain of water. It's a stream
of warm air being forced out of the whales lungs -- - its his breath.
Some whale watch guides can tell you the kind of whale that has
just come to the surface, even before they see the animal, based
on the height and shape of their spout.
How Can You Tell Which Whale You are Looking At?
We use the name whale for about 70 kinds of animals. So how can
you tell who is who? Not all 70 kinds live in the area around Cape
Cod. In fact, some don't even live in the Atlantic Ocean. But even
the dozen or so that live are found in the northeast are different
and easy to identify.
Remember, the category whale includes dolphins and porpoises. First
- look at the animal's size. Most dolphins are less than ten feet
long; porpoises are not much more than six feet. Whales are much
bigger, some are as long as a large airplane. Next - look at its
mouth. Dolphins and a few whales have teeth for catching their food.
All the other whales have baleen - plates with fringe that hang
from their upper jaws and trap their food, like a sieve. An easy
way to tell if a whale uses teeth or baleen to catch food is to
count the number of blowholes - breathing holes - on the top of
their heads. Toothed whales have only one blow hole, baleen whales
have two. Near Cape Cod the toothed whales that you'll see most
often are dolphins, smaller animals with patterns on their sides,
or pilot whales, black animals with a white patch under their chins
and a square head. The baleen whales you'll most likely see are
humpbacks, large animals with exceptionally long flippers, up to
12 feet in some cases.
Humpback whales have flat heads and a small fin on their backs.
Another kind of baleen whale is the right whale. It has a large,
square head and no fin. Now when you see a whale or a picture os
a whale, see if you can guess the kind of whale - check its size,
count the number of blowholes, look at the shape of its head, the
size of the fin on its back, and the length of its flippers.
Sallie K Riggs is the President of the National Marine Life
Center, Inc., developing a rehabilitation hospital for stranded
whales, dolphins, seals and sea turtles.
|
