Endangered Animals - Blue Whales

Endangered Animals--Blue Whales The blue whale is the biggest animal that has ever lived on land or water. The biggest land animal, the African elephant, could stand on the blue whale's tongue! Even the biggest dinosaur that ever lived was only about one-fourth the size of a blue whale.

Whales are, of course, mammals. They are warm-blooded, breathe air, produce milk for their young, and have fur or hair (sort of). The only actual hair on most whales is a few bristles around their lips and snout.

Both whales and dolphins belong to a group of mammals known as cetaceans. Cetaceans are divided into two groups -- the baleen whales and the toothed whales with the following characteristics:

BALEEN WHALES

Have 2 blowholes

Have baleen plates in their mouths instead of teeth

Feed mainly on krill and plankton and other very small marine animals

Have large mouths and small throats

TOOTHED WHALES

Have 1 blowhole

Have up to 250 teeth

Have asymmetrical skulls

Feed mainly on fish

Have wider throats since their prey is larger

A blue whale is a baleen whale which means that it has long plates which are like huge fringed brushes growing down from the upper jaws. These are used to strain the food from the water. They feed mostly on krill which is a small, shrimp-like animal.

Blue whales belong to a species of baleen whales called rorquals. Rorquals have throat-grooves or pleats, which allow their throats to expand and gulp huge amounts of water.

Whales in general can reach huge sizes because their weight is supported by water. If the larger whales such as the blue whale or sperm whale are beached, they cannot support their own weight. The weight of their bodies presses down on their lungs and inhibits their breathing to the point where they may suffocate and die. Their other internal organs may be crushed, as well. Even their skeletons cannot support the size of these whales without the benefit of the buoyancy of water, and they may suffer from broken backs.

Come and sample these blue whale internet sites.

Time Out for Whale Facts

Most whales do not have eyelids. They rely on thick oily tears to protect their eyes.

Marine Mammal Center - BlueWhale
http://www.marinemammalcenter.org/learning/education/whales/blue.asp

In terms of color and the shape of their body and fins, describe what a blue whale looks like.
About long is gestation (the amount of time that an animal is pregnant) in a blue whale?
The milk that we buy in the grocery store usually has a 2% or 1% fat content. What is the fat content of blue whale milk? How much weight can a whale calf gain in just 1 hour?
While was it difficult for 19th century whalers to kill blue whales? In the early part of this century, what made it easier to hunt them?
About how many blue whales were killed in just the year 1931?

Blue Whale
http://www.seaworld.org/animal-info/animal-bytes/animalia/eumetazoa/coelomates/deuterostomes/chordata/craniata/mammalia/cetacea/blue-whale.htm

Blue whales are, of course, enourmous. They used to be even bigger. Why are they somewhat smaller now?
There are now laws that protect blue whales. Are their numbers increasing?

Time Out for Whale Facts

Whales do not have good vision underwater, but they do have good hearing. They use a system known as echo location which utilizes a series of sounds and echoes to help them find their way and to locate their food.

Blue Whales
http://www.whalesongs.org/cetacean/blue_whale/home.html

Blue whales are known by what other name? How did they get this name?
What is the geographical distribution of blue whales?
Describe what a blue whale looks like.
What is a blue whale's habitat? Don't just say "the ocean". Be specific.

Krill
http://www.oceanlight.com/html/krill.html

Check out this photo to see what a krill looks like. They are only about 1/2 inch long, and yet they are the main food source for many baleen whales.

Time Out for Whale Facts

Blue whales depend on their huge tail flukes for movement and speed. If pressed, blue whales can swim up to 21 knots per hours which is about the speed of an ocean liner. Unlike most other whales, the tail flukes of a blue whale usually remain submerged in the water when the whale is swimming at the surface and even stay submerged when the whale makes a dive. Since whales are often identified by their tail flukes, this makes it difficult to pinpoint blue whales.

Blue Whale Photos
http://www.oceanlight.com/html/blue_whale_topside.html

Check out these amazing photos of blue whales coming to the surface and FIND WORD FOR DIVING OR SLAPPING THEIR TAILS. You can also see photos of blue whales under water.
When a blue whale sends water out its blow hole, how high can that stream of water be?
The photographer who took these photographs says that seen from a distance, blue whales resting or swimming just below the surface appear to be what?

Time Out for Whale Facts

Whales migrate to warmer water to mate, give birth, and raise their young calves. Because they are mammals and need to breathe air, baby whales are usually born tail first. As soon as they are born they must quickly reach the surface of the water to take in their first breath or else they would drown. The milk of mother whales is rich and high in fat content, and whale calves gain weight and grow very quickly. They need a thick layer of blubber to survive the cold waters of the arctic or antarctic where they will eventually migrate with their mothers.

Blue Whales
http://www.acsonline.org/factpack/bluewhl.htm

How do blue whales communicate with each other?
Why are blue whales sometimes called sulfur bottoms?
What color are the baleen plates in a blue whale? How long are they?
Where do blue whales in the northern hemisphere move in the summertime to feed?
Where do blue whales in the southern hemisphere move in the summertime to feed?
What is the average swimming speed for a blue whale?
Why was a Norwegian man, Sven Foyn, no friend to blue whales?
How much oil could be obtained from a 90 foot blue whale?

WhaleNet Scientists
http://whale.wheelock.edu/whalenet-stuff/ASK_SCI.html

If you have a specific question that you would like to ask about blue whales, you can email one of the marine biologists/whale experts and WhaleNet and they will respond.

Time Out for Whale Facts

Whales talk to each other by making high pitched sounds like whistles, clicks, squeaks, rattles, and groans.

Time Out for Whale Facts

The gyser of water coming from the blow hole of a blue whale can be as high as 30 feet.

Bibliography

Papastavrou, Vassili. Whale. Alfed Knopf : New York, 1993.

Prevost, John. Blue Whales. Abdo & Daughters : Edina, Minnesota, 1995.

Author: LINDA MOSBACKER - Email linda.mosbacker@slc.k12.ut.us