whales
overview
Whales roam throughout all of the world's oceans, communicating with complex and mysterious sounds. Their sheer size amazes us: the blue whale can reach lengths of more than 100 feet and weigh up to 200 tons—as much as 33 elephants.
Despite living in the water, whales breathe air. And like humans, they are warm-blooded mammals who nurse their young. A thick layer of fat called blubber insulates them from cold ocean waters.
Some whales are known as baleen whales, including blue, right, bowhead, sei, and gray whales. This refers to the fact that they have special bristle-like structures in their mouths (called baleen) that strain food from the water. Other whales, such as beluga or sperm whales, have teeth.
Beluga
Belugas are extremely sociable mammals that live, hunt and migrate together in pods, ranging from a few individuals to hundreds of whales. Their bulbous forehead, called a "melon", is flexible and capable of changing shape. This allows them to make different facial expressions. Belugas can produce a series of chirps, clicks, whistles and squeals, which give the beluga its other name, "the canary of the sea." They may sound like music or even nonsense to us, but to fellow belugas they convey important information.
Many populations of belugas migrate as the sea ice changes in the Arctic. They move south in the fall as the ice forms and then return to feed again in the spring, as the ice breaks up. They can also be found near river mouths, and sometimes even venture up river. Belugas feed on a variety of fish species, such as salmon and herring, as well as shrimp, crabs and mollusks.
grey
Gray whales have a hump and a ridge of sharp bumps along their backs, instead of a dorsal fin. They are a type of baleen whale, which means they filter food from the water through special bristly structures in their mouths. Gray whales stay close to shore and feed in shallow water. Their well-known migrations take them between feeding and breeding areas, swimming as much as 12,000 miles round trip.
Critically endangered western gray whales migrate into their summer feeding grounds near Sahkalin Island, Russia in late May or early June and return to their winter feeding grounds in the South China Sea in late autumn. Summer feeding grounds for the eastern population lie in the Bering and Chukchi Seas between Alaska and Russia. In the winter, these eastern gray whales migrate south along the west coast of the US to Mexico to breed and have their calves.
north atlantic right
The North Atlantic right whale can easily be identified by the white calluses on its head, which are very noticeable against the whale's dark gray body. It has a broad back without a dorsal fin and a long arching mouth that begins above the eye. A baleen whale, it feeds by swimming through a swarm of plankton with its mouth open and the head slightly above the surface. Right whales are found more often in coastal waters, especially during the breeding season.
bowhead
This predominantly Arctic species is associated with ice floes. Its movement patterns are therefore influenced by the melting and freezing of the ice.
Bowhead whales are capable of breaking through sea ice at least seven inches thick with their large skulls and powerful bodies.
Adult bowheads are entirely black except the front part of the lower jaw which is white and prominently upturned. They can grow up to 60 feet long while still being able to leap entirely out of water. Bowheads filter their food through baleen by opening their mouths and straining plankton from the surface, the water column, or the sea floor.
Data has shown that bowhead whales may be among the longest-lived animals on earth. Based on the recovery of stone harpoon tips in their blubber, and from analysis of eye tissue, scientists believe that the life-span of bowhead whales can be over 200 years.
fin whale
Some scientists have speculated that fin whales circle schools of fish with the white side facing the prey and frightening them into denser schools that are easier for the whale to catch. The fin whale, like other baleen whales, strains its food from the water through baleen plates.
Next to the blue whale, the fin whale is the second largest mammal in the world. They have a distinct ridge along their back behind the dorsal fin, which gives it the nickname "razorback." Fin whales have a very unusual feature: the lower right jaw is bright white and the lower left jaw is black.
sei
The sei whale is one of the fastest whales, reaching speeds of up to 30 miles per hour. Sei whales inhabit all oceans and adjoining seas except in tropical and polar regions. Like other great whales, they prefer to spend the summer feeding in cooler waters before migrating to warmer waters to breed and give birth to their calves.
blue
The blue whale is the largest animal on the planet, weighing as much as 200 tons (approximately 33 elephants). The blue whale has a heart the size of a Volkswagen Beetle. Its stomach can hold one ton of krill and it needs to eat about four tons of krill each day. They are the loudest animals on Earth and are even louder than a jet engine. Their calls reach 188 decibels, while a jet reaches 140 decibels. Their low frequency whistle can be heard for hundreds of miles and is probably used to attract other blue whales.
narwhal
The narwhal looks like a cross between a whale and a unicorn with its long, spiraled tusk jutting from its head. Males most commonly have tusks, and some may even have two. The tusk, which can grow as long as 10 feet, is actually an enlarged tooth. Ongoing research by WWF collaborators indicates that the tusk has sensory capability, with up to 10 million nerve endings inside. The tusk may also play a role in the ways males exert dominance.
Narwhals spend their lives in the Arctic waters of Canada, Greenland, Norway and Russia. The majority of the world's narwhals winter for up to five months under the sea ice in the Baffin Bay-Davis Strait area (between Canada and western Greenland). Cracks in the ice allow them to breathe when needed, especially after dives, which can be up to a mile and a half deep. They feed mainly on Greenland halibut, along with other fish, squid and shrimp.