Species Fact Profile: Beluga (Delphinapterus leucas)

Beluga

Delphinapterus leucas (Pallas, 1776)

Range: Arctic Circle
Habitat: Arctic waters near ice edge, shallow bays, estuaries
Diet: Fish, Marine Invertebrates
Social Grouping: Highly social, in summer may congregate in the thousands
Reproduction: Sexually mature at 4-9 years old (females mature earlier than males).  Mate from late February through early April.  Males chase the females and ward off other males until the female is ready to mate.  A single calf is born after a one year gestation.  Calves lack blubber at birth and are born in river mouths, where the water is warmer.  Weaning takes place during the second year.  Females breed every 2-3 years
Lifespan: 35-50 Years
Conservation Status: IUCN Near Threatened, CITES Appendix II

• Boy length is 3.5 meters.  Weight is 500-1500 kilograms, with half of that weight being fat (the blubber layer may be 15 centimeters thick in winter).  Males are larger than females
• The stocky body ends in a small head with a very flexible neck, unusual among cetaceans.  The heavy head can be used to create breathing holes in the ice during the winter.  The enlarged melon on the forehead aids in vocalizations.  The lips are very flexible, allowing the beluga to display a variety of facial expressions.
• Calves are grey when born, but turn white with age.  Prior to the summer molt they turn yellow, turning white again after rubbing their withered old skin off on gravel beds.
• Latin name translates to "white dolphin without a wing", referencing their lack of dorsal fins
• The word "Beluga" comes from the Russian for "white"  - the name is also given to a species of sturgeon
• Most of their prey is found on the seabed.  They can dive to depths of nearly 1000 meters, but generally stay in shallower waters.  Prey is gripped with their flexible lips and often swallowed whole.
• Communicate with a variety of clicks, grunts, squeals, and whistles, loud enough to be heard through the hulls of ships.  This has earned them the nickname "Sea Canaries"
• Often observed plying with objects in the water, sch as wood, plants, dead fish, or bubbles, either alone or in groups.
• Rarely breach, but sometimes bob a third of their body out of the water
• Their only significant natural predators are orcas (killer whales) and polar bears, which may attack them when they are trapped in the ice
• The only member of the genus Delphinapterus; their closest relative is the narwhal
• Major threats include pollution, with the accumulation of toxins leading to deformed calves, and global climate change.  Some sub-populations are more threatened then others and receive special protection.
• Traditionally hunted for blubber, which became unsustainable during the era of commercial whaling.  They are easy to hunt due to their fidelity to certain migratory routes.  Today local peoples are still permitted to hunt them for food.