Giants of the sea
It was a bright July day. The calm sea off the northern coast of Norway
sparkled in the sunlight. A flock of birds wheeled overhead.
Suddenly an enormous, dripping, dark-gray shape shot up out of the
water. Its huge, open mouth was filled with what looked like a gray
fringe. The big, curved body was fully fifty feet (15 meters) long.
For a moment the animal seemed to hang in the air. Then it crashed back
into the water and vanished in a torrent of spray. It was a humpback
whale leaping about in play!
For thousands of years, people thought that whales were giant fish. But
today we know that they are mammals. Although whales look like fish, you
can quickly tell them apart by the tail. Fish have vertical, or straight
up and down, tail fins. Whales have sideways tail fins. Whales swim by
moving their flukes, or tail fins, up and down. Most fish swim by moving
their tail fins from side to side.
When a whale comes to the surface, what looks like a fine watery mist
spouts into the air out of the whale’s head. Many people think the spout
is water, but it isn’t. It is the whale’s steamy breath.
When a whale is ready to dive, it fills its lungs with air. While it is
underwater, the whale holds its breath. Whales can stay underwater for a
long time—some kinds for more than an hour.
While a whale is underwater, the air in its lungs grows warmer and
warmer. When the whale comes up to take another breath, it lets
the warm air out of its lungs with a great whoosh. The air comes out
through the whale’s blowhole, which is on top of its head. When the hot
air from the whale’s lungs hits the colder air over the water, it makes
a cloud of steam. You do the same thing when you blow warm air out of
your mouth on a cold day.
Whales have no sense of smell, and most have poor eyesight. But their
senses of touch and hearing are very good. They \”talk” with one another
by making squeaking sounds. They can hear these squeaks over great
distances.
People have hunted whales for hundreds of years. So many of some kinds
have been killed that there aren’t many of them left. It may not be long
before these huge animals disappear forever from the sea.
