Delphinapterus leucas
beluga

Beluga whales inhabit the arctic and sub-arctic waters along the coast of Canada, Alaska, Greenland, Norway, and the Soviet Union. About 500 of them inhabit the waters of the St. Lawrence River. (Bonner, 1989)

The habitat of beluga whales includes inlets, fjords, channels, bays, and the shallow waters of the artic seas that are warmed by continuous sunlight. They are also found at the mouths of river during summertime, where they feed, socialize, and deliver their offspring. These waters are usually 8 to 10 degrees celsius. (Paine, 1995)

The beluga is also known as the white whale for its milky white skin. It is the only species of whale that is entirely white, although it is born gray and fades gradually with age. These whales lack a dorsal fin, but have a shallow ridge along their back. Their appendages are narrower and pointier than that of the narwhal. Belugas also have a melon-shaped head, which is the center for echolocation. They are 3 to 5 meters and length and weigh an average of 1.6 tons (3500lbs). Fifty percent of their weight is fat, a marked increase relative to other non-arctic whales, whose body is only twenty percent fat. The blubber is 10cm thick in belugas. Belugas are sexually dimorphic, with the males being slightly larger than the females. Females average 1,350 kg and males 1,500 kg in weight. (Paine, 1995)

There is either thought to be spontaneous ovulation with an extremely long gestation period or delayed implantation with a shorter gestation period, but it is unknown. Their development is similar to that of most other mammals. (Lentifer 1988)

The mating system of these whales has not been described.

Belugas tend to mate from late February to early April. The males chase down the females, making all sorts of noises. The male throws down his tail and bends violently, then he throws his head up and down as his melon vibrates to ward off any other males who might attempt to mate with this female.

The male and female swim in harmony and caress each other, until she swims underneath his belly. She puts her belly up against his and they continue to swim in harmony with each other. They mate only with absolute consent. (Paine, 1995)

Gestation lasts about fourteen months. However, it is a possibility that these creatures have delayed implantation. A calf is born during the summer months of May through July. The calf is very well developed and has a grayish coloration. The nursery pod stays around during the delivery and then all of them take off except a young teenage nursemaid. This usually happens near rivers because the water is ten degrees warmer there. This is important for the calf, which does not have as much blubber as a full grown adult. The baby stays in-between the two females as they swim pulling him with the current. The calf is totally dependent on the mother’s milk for a year, but lactation lasts 1.5 to 2 years.

It takes 4 to 7 years for females to sexually mature, and it takes 7 to 9 years for males. (Bonner, 1989)

Females reproduce every 2 to 3 years. Females stop reproducing in their early twenties. (Lentifer, 1989) (Bonner, 1989; Lentifer, 1988; Paine, 1995)

Offspring are precocious, and able to swim along side their mothers from birth. The mother provides protection and guidance for the offspring, as well as milk. A female beluga can lactate for up to two years. (Paine, 1995)

The life span for females is thought to be about 32 years and that for males about 40 years. Predation and ice entrapment are common causes of premature death. (Lentifer, 1988)

Belugas aggregate in herds of hundreds to thousands. Grouping of different pods is still uncertain, but age and sex seem to play a role in the grouping. Five to ten percent of a beluga's time is spent at the surface of the water. They rarely are seen breeching, although they bounce vertically out of the water about one third of the body length. They swim about 9 to 10 km per hour. Belugas are constantly vocalizing and swimming around, over, and under each other. They also play with objects in the water together or by themselves. These objects are not limited to wood, plants, dead fish, and bubbles that they created. (Paine, 1995)

Information on the home range size of these animals is not available.

Communication is achieved by using the melon for echolocation. Belugas have a high frequency level of communication. Their voices are so loud that they sound like birds, which is why they were once nicknamed “sea canaries”. They are considered to be among the most vocal species of cetaceans. They use their vocalizations for echolocation, mating, and communication. Their voices sound like chirps, whistles, and squawks. Belugas also use body language such as grinding their teeth or splashing around. Some communication undoubtedly occurs when babies are in contact with their mothers. (Bonner, 1989; Paine, 1995)

Belugas feast on a variety of prey including smelt, flatfish, flounder, sculpins, salmon, and cod. They also feed on invertebrates such as crab, shrimp, clams, worms, octopus, squid, and other bottom dwelling creatures. Since they don’t have many big, sharp teeth to grab their prey, they use suction to trap it into their mouths. Consequently, everything must be eaten whole. Prey cannot be too large, therefore, or the beluga will choke on it. (Lentifer, 1988; Paine, 1995)

The known predators of belugas are killer whales and polar bears. Polar bears will attack belugas in the same way they would attack a seal, which entails lying in wait at breathing holes. Killer whales come around August. Belugas can usually hear killer whales, so this makes it difficult for killer whales to attack them. Also, the conspicuous fin makes it almost impossible for a killer whale to maneuver in ice. Humans used to hunt belugas for their skin and oil, but that is not so common anymore. (Paine, 1995)

Belugas consume many fish, especially since they travel in herds of between one hundred and a thousand. This undoubtedly causes some regulation of fish populations. Belugas also seem to have a parasite called Pharurus pallasii, thought to infect the hearing organs. However, it is not known if this parasite is harmful to the beluga. (Lentifer, 1988)

Belugas were once hunted for food and other items such as oil. These provided humans with a profit. Now, because of their large social groupings, they provide ecotourists with entertainment. (Lentifer, 1988)

Belugas hinder fishermen from getting any fish. Much of the hunting of belugas has died down since the seventies. (Lentifer, 1988)

Currently, beluga populations have been estimated at 60,000 to a 100,000 so there is no need for conservation efforts, although it couldn’t hurt.