Latin Name: Delphinapterus leucas
Habitat: Arctic waters of Northern Alaska, the Bering Sea,
Cook Inlet, North America, Europe and Asia
Classification: Mammal, carnivore
If you stand on the hard ice and frozen shores of Alaska, you might be lucky enough to hear a song that no bird or human can naturally create.
Beluga whales are one of only three species of whales that live their entire life in Arctic waters. They carry the nickname of "Sea Canary" because of their loud songs. The members of this extremely social group of whales travel the ocean in groups called pods. They communicate with each other with "echolocation." This means they make sharp calls, clicks, and songs that allow them to locate predators, objects, and other whales by the response of the echo. Submarines use the same technique to locate other ships in the waters. By sending sounds through dark waters, beluga whales can determine the size, shape, and direction of obstacles and predators.
Think about it: Why is a beluga like a submarine?
Oddly enough, the beluga whale's "melon" is an important organ for communication. This "melon" is a round, fatty section on the tops of their heads. It is very sensitive to sound and vibration, and helps beluga whales to "feel" returning echoes from the sounds they make. Adult beluga whales are the only all-white whales, although they are usually bluish-gray when they are young. They have no dorsal fin, only ridges on their backs that are rarely visible from a distance. They have plump, fleshy bodies and rounded fins. Adult beluga whales are usually about 15 feet long and weigh between two and three thousand pounds. Belugas are fairly slow swimmers, usually traveling at speeds of six to seven knots. They can swim quickly at around 14 knots, but only over short distances.
Beluga whales have an important attribute that allows them to move and search food with special flexibility. Imagine what you would do if you couldn't shake your head. Or glance down at your toes. What would you do? Spin around in circles? Well, most whales have to move their whole bodies just to turn and look. But unlike most whales, beluga whales' backbones are not fused to their heads. They can move their necks from side to side, without shifting the direction of their entire bodies.
Think about it: How do belugas "hear" through their melons?
Beluga whales usually don't dive for more than 15 or 20 minutes. This can cause a big problem during cold winter months, when arctic ice is thick. Scientists still marvel at beluga whales' sharp underwater ability to locate objects. Belugas use echolocation to sense thin holes in the ice and pockets of trapped air. Their blowhole muscle is relaxed when it is closed. When they surface, they contract the muscle and suck in enough oxygen to last them for another dive.
Think about it: How long can you hold your breath?
Belugas use two rows of thirty to forty cone-shaped teeth to trap and tear their prey. Their teeth are not designed for chewing, they usually swallow their food whole. They eat fish, crustaceans and squid. Belugas have two main natural predators: killer whales and polar bears. Both of these predators attack young belugas, but may hunt adults if necessary. Because belugas are most comfortable in shallow water, polar bears often wait for them to get trapped or surface between sections of ice. The bears can then paw and grab a beluga, pulling it out of the water for a feast.
Think about it: Look at the shape of your teeth in the mirror. Compare the back teeth, your molars, to those in the front. How are they different? Why?
At one time, beluga whale numbers were rapidly declining. Because they move slowly in pods through shallow water, they are easily hunted and trapped by humans. A small group of the species lives in the shallow waters of Cook Inlet. In the 1930s, residents attempted to establish a beluga fishery in the inlet. They spread a net across the Beluga River and trapped about 100 belugas at high tide. Large-scale beluga hunting is rare today, but Native Alaskans still hunt belugas for meat, oil, and muktuk, a layer of skin and fat that they cook in oil and eat.
Think about it: If you've ever stopped along Turnagain Arm during a salmon run, you may have seen bright flashes of white in the gray waters of Cook Inlet. Those are beluga whales. Why do you suppose they are following the salmon?
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Image provided by Anchorage Daily News.
Image provided by Anchorage Daily News.
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