Delphinapterus leucasbeluga

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Geographic Range

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)

Habitat

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)

  • Terrestrial Biomes
  • icecap
  • Range depth
    0 to 350 m
    0.00 to 1148.29 ft

Physical Description

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)

  • Sexual Dimorphism
  • male larger
  • Average mass
    "1,350-1,500" kg
    lb
  • Average mass
    1.43e+06 g
    50396.48 oz
    AnAge
  • Range length
    300 to 460 cm
    118.11 to 181.10 in
  • Average length
    400 cm
    157.48 in

Development

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)

Reproduction

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)

  • Breeding interval
    Female belugas generally reproduce once every two to three years.
  • Breeding season
    Breeding occurs from late February through early April.
  • Range number of offspring
    1 to 1
  • Average number of offspring
    1
    AnAge
  • Average gestation period
    14 months
  • Average gestation period
    416 days
    AnAge
  • Range weaning age
    12 to 24 months
  • Range time to independence
    12 to 24 months
  • Range age at sexual or reproductive maturity (female)
    4 to 7 years
  • Range age at sexual or reproductive maturity (male)
    7 to 9 years

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)

  • Parental Investment
  • precocial
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female

Lifespan/Longevity

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)

  • Range lifespan
    Status: wild
    32 to 40 years
  • Typical lifespan
    Status: wild
    25 to 30 years

Behavior

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)

Home Range

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

Communication and Perception

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)

Food Habits

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)

  • Animal Foods
  • fish
  • mollusks
  • aquatic or marine worms
  • aquatic crustaceans

Predation

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)

Ecosystem Roles

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)

Economic Importance for Humans: Positive

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)

  • Positive Impacts
  • food
  • ecotourism
  • research and education
  • produces fertilizer

Economic Importance for Humans: Negative

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

  • Negative Impacts
  • crop pest

Conservation Status

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.

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Shavon Williams (author), Humboldt State University, Brian Arbogast (editor), Humboldt State University.

Glossary

Arctic Ocean

the body of water between Europe, Asia, and North America which occurs mostly north of the Arctic circle.

Pacific Ocean

body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.

World Map

acoustic

uses sound to communicate

benthic

Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones. Bottom habitats in the very deepest oceans (below 9000 m) are sometimes referred to as the abyssal zone. see also oceanic vent.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

brackish water

areas with salty water, usually in coastal marshes and estuaries.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

coastal

the nearshore aquatic habitats near a coast, or shoreline.

delayed implantation

in mammals, a condition in which a fertilized egg reaches the uterus but delays its implantation in the uterine lining, sometimes for several months.

echolocation

The process by which an animal locates itself with respect to other animals and objects by emitting sound waves and sensing the pattern of the reflected sound waves.

ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

estuarine

an area where a freshwater river meets the ocean and tidal influences result in fluctuations in salinity.

fertilization

union of egg and spermatozoan

food

A substance that provides both nutrients and energy to a living thing.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

migratory

makes seasonal movements between breeding and wintering grounds

molluscivore

eats mollusks, members of Phylum Mollusca

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nomadic

generally wanders from place to place, usually within a well-defined range.

pelagic

An aquatic biome consisting of the open ocean, far from land, does not include sea bottom (benthic zone).

piscivore

an animal that mainly eats fish

saltwater or marine

mainly lives in oceans, seas, or other bodies of salt water.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

young precocial

young are relatively well-developed when born

References

Bonner, W. 1989. Whales of the World. New York: Facts on File Publications.

Lentifer, J. 1988. Selected Marine Mammals of Alaska: Species Accounts with Research and Management Recomendations. Washington, D.C.: Marine Mammals Commission.

Paine, S. 1995. The World of the Arctic Whales. San Francisco: Sierra Club.