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Beluga Whale (Delphinapterus leucas)

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The beluga whale is a small, white-toothed whale. Adult belugas may reach a length of 16 feet (5 m), though average size is 12-14 feet (about 4 m). Males may weigh about 3,300 pounds (1,500 kg) and females 3,000 pounds (1,360 kg). Beluga whales lack a dorsal fin and do not typically produce a visible “blow” when breathing at the surface.

Unlike other cetaceans, belugas can move their head up, down, and side to side, because their cervical vertebrae are not fused. This feature appears to be an adaptation to maneuvering and catching prey in muddy or ice-covered areas.

Beluga whales are covered with a thick layer of blubber that accounts for as much as 40 percent of their body mass. This fat provides thermal protection and stores energy. Belugas are unique among cetaceans in that they shed their outer layer of skin, or molt, each summer around July. They concentrate in shallow water where there is coarse gravel to rub against. The rubbing action helps remove the top layer of old yellow skin and reveal the new skin underneath. However, there is no evidence that Cook Inlet beluga whales go through a molt.

Beluga whales mate in the spring, usually in March or April, in small bays and estuaries. Gestation lasts about 14-15 months, and calves are born between March and September, mostly between May and July. Females give birth to single calves every two to three years on average. We do not have precise information on mating of Cook Inlet belugas, estimating that mating occurs between late winter and early spring with calves appearing in mid-July based on surveys and April – August based on Native hunter traditional knowledge.

Belugas give birth where the water is relatively warm, as newborn calves lack a thick blubber layer and benefit from the warmer water temperatures of shallow tidal flats and estuaries. Beluga calves nurse for at least 12 to 18 months, until their teeth emerge, at which point they supplement their diets with shrimp and small fishes. Most calves continue to nurse for another year after beginning to eat solid food. Female belugas are old enough to reproduce at around 4 to 7 years of age and males around 7 to 9 years. Their lifespan is thought to be about 35-50 years, however using the one growth layer group per year (on teeth) theory Cook Inlet belugas may live 60-70 years.

Belugas are extremely social animals that typically migrate, hunt, and interact together in groups of 10 to several hundred. They are known as the “canaries of the sea,” because they produce a vast repertoire of sounds including whistles, squeals, moos, chirps, and clicks. They have a well-developed sense of hearing and echolocation, and are reported to have acute vision both in and out of water.

Belugas are opportunistic feeders, eating octopus, squid, crabs, shrimp, clams, mussels, snails, sandworms, and fishes, including eulachon, salmon, capelin, cod, herring, smelt, flounder, sole, sculpin, lamprey, and lingcod.

This species is classified as NEAR THREATENED according to the IUCN's Red List.
This species is classified as NEAR THREATENED according to the IUCN’s Red List.

Status

ESA Endangered – Cook Inlet DPS (Alaska)
MMPA Depleted – Cook Inlet (Alaska), Sakhalin Bay-Nikolaya Bay-Amur River stock
CITES Appendix II – throughout its range

Species Description

Weight:
average 3,150 lbs (1,430 kg)
Adult females average up to 2,998 Ibs (1360 kg); adult males average up to 3307 Ibs
(1500 kg). At birth, Alaska beluga calves have been reported to average 159 Ibs (72 kg).
Length:
average 13 feet (4 m), but may reach 16 feet (5 m)
Adult females average 11.6 feet (3.55 m); adult males average 13.6 ft (4.15 m). At birth,
Alaska beluga calves have been reported to average 4.9 ft (1.5 m).
Appearance:
Born very dark grey or brownish-grey, belugas gradually lighten up to white as they mature.  Instead of a dorsal fin, belugas have a tough dorsal ridge. They have a very bulbous, flexible melon on their forehead they use to produce and focus sound..
Lifespan:
35-50 years, or using the one growth layer group (teeth) per year theory 60-70 years
Diet:
opportunistic feeders, belugas eat invertebrates such as octopus, squid, crabs, shrimp, clams, mussels, snails, sandworms, and a variety of fishes including salmon, eulachon, cod, and, flounder.
Behavior:
extremely social animals that typically migrate, hunt, and interact together in groups or single; known as the “canaries of the sea,” because they produce a vast repertoire of sounds including whistles, squeals, moos, chirps, and clicks This link is an external site.. Cook Inlet beluga whales do not migrate, instead they remain in Cook Inlet year-round.

RELATIVE SPECIES: Narwhal, they are often confused for Harp Seals

OTHER NAMES: White Whales

NEIGHBORING SPECIES: Narwhal, Bowhead whale

PREDATORS: Humans, killer whales and polar bears.

THREATS: Hunting by Alaskan natives. Industrial run-off and oil exploration has caused strandings. Often become trapped under ice which causes starvation, suffocation and attacks by polar bears. About 1 beluga a year is killed by a killer whale. Belugas become stranded because they are trying to avoid killer whales.

DIET: Salmon, cod, herring, capelin, squid, octopus, shrimp, crabs, and zooplankton.

MANNER OF FEEDING: Most of their prey are bottom dwellers. Belugas dive deep to suction up their prey with their puckered lips. Can shoot a stream of water to uncover hiding prey. Groups of 5 or more belugas will herd schools of fish to make preying easier. They have a flexible neck, which gives them a better range of motion for catching prey in muddy or icy waters.

BEHAVIOR: “The Canaries of the Sea” they make many sounds such as chirping, squeals, clicks and will even imitate the noise made by scuba divers. They “molt” or lose their top layer of skin every summer, they stay in shallow water in order to rub off the molting skin on the substrate. Extremely social, they travel, hunt and migrate in pods of 10 to several hundred, often of the same sex and age. They often migrate with bowhead whales. Can shoot streams of water with its mouth. They are able to nod and move their heads in any direction. Well developed sense of hearing and echolocation. A single large male will lead the pod, females split off from pod when calving. They chase each other playfully and aggressively, as well as rubbing up against one another. Females in the wild and captivity have been seen carrying objects in their mouths and on their backs during calving season or after they have lost their calf. This may be surrogate behavior. Very curious of people and boats.

REPRODUCTION: Become sexually mature from 3-9 years (males 7-9). Mating occurs during the spring in shallow estuaries. Gestation is 14-15 months. Calves are born in warmer waters. Rarely give birth to twins. Calves are weaned at 20-24 months. Females give birth every 2-3 years. Mothers with calves stay away from pods of males.

LIFE SPAN: 25-30 years

Habitat

Beluga whales are generally found in shallow coastal waters, often in water barely deep enough to cover their bodies, but have also been seen in deep waters. They seem well adapted to both a cold ocean habitat and a warmer freshwater habitat. Belugas can be found swimming among icebergs and ice floes in the waters of the Arctic and subarctic, where water temperatures may be as low as 32° F (0° C). They can also be found in estuaries and river basins.

Critical Habitat

NMFS proposed to designate critical habitat for the Cook Inlet beluga whale DPS on December 2,2009 (74 FR 63080); two areas were proposed, consisting of 7,809 square km (3,016 square miles) of marine habitat. On April 11,2011, NMFS published the final rule designating the two areas (minus and exclusion zone) of Cook Inlet as critical habitat for the Cook Inlet beluga whales (76 FR 20180; 50 CFR part 226.220).

Distribution

Beluga whales are circumpolar in distribution. Beluga whales inhabit the Arctic and subarctic regions of

  • Russia
  • Greenland
  • North America

Specifically, they inhabit the Arctic Ocean and its adjoining seas, including the

  • Sea of Okhotsk
  • Bering Sea
  • Cook Inlet portion of the Gulf of Alaska
  • Gulf of Alaska
  • Beaufort Sea
  • Baffin Bay
  • Hudson Bay
  • Gulf of St. Lawrence

During certain times of the year, belugas may also be found in large rivers, such as the Yukon, as they seem to be unaffected by salinity changes.

Population Trends

In the U.S., there are distinct stocks of beluga whales–all in Alaska–of which the Cook Inlet DPS is the only ESA-listed population. It is the most isolated population; genetic samples suggest these whales have been isolated for several thousand years. The Cook Inlet stock has been severely reduced in numbers over the last several decades. We estimate this population numbered as many as 1,300 in the late 1970s. The 2014 estimate is about 340 beluga whales in the Cook Inlet. Population size estimates from the most recent Stock Assessment Reports are available on our website.

Threats

For Cook Inlet belugas, potential threats identified in the draft recovery plan include:

  • threats of high concern: catastrophic events (e.g., natural disasters; spills; mass strandings); cumulative and synergistic effects of multiple stressors; and noise.
  • threats of medium concern: disease agents (e.g., pathogens, parasites, and harmful algal blooms); habitat loss or degradation; reduction is prey; and unauthorized take.
  • threats of low concern: subsistence hunting; pollution; and predation.

Historical threats for belugas include

  • harvest, for food and skin/leather
    • Belugas are the only cetacean with skin thick enough to be used as leather when tanned
  • legal subsistence harvest in the Cook Inlet
    • Reported subsistence harvests of Cook Inlet beluga whales between 1994 and 1998 can account for the 14 percent annual rate of decline in the population during that time period.
    • The known annual subsistence harvest by Alaska Natives during 1995-1998 averaged 77 beluga whales per year. This level of harvest was unsustainable, and the drastic population decline from 1994-1998, prompted the “depleted” designation under the MMPA.
    • Between 1999 and 2015, only five Cook Inlet beluga whales have been taken through a subsistence harvest.

The other 4 Alaskan stocks have levels of subsistence harvest that do not threaten their survival

Conservation Efforts

In 2008 we published a Conservation Plan for the Cook Inlet beluga whales [pdf] that details many proposed and current conservation actions. The plan sets a goal of a minimum population of 780 animals before we would no longer consider the Cook Inlet stock depleted under the MMPA. Achievement of this goal is expected to take until at least 2038. Management of the Alaska Native subsistence hunts in Cook Inlet occurred through a Cooperative Agreement between NMFS and the Cook Inlet Marine Mammal Council. (Note: CIMMC was disbanded by unanimous vote of the then CIMMC member Tribes’ representatives on 6/20/2012.)

On May 15th, 2015 we published a draft recovery plan for the Cook Inlet beluga whales under the ESA. The ultimate goal of the recovery plan is to guide efforts to recover Cook Inlet beluga whales by meeting the criteria identified in the plan and addressing the threats that resulted in their listing under the ESA.

A co-management agreement is in place for the native subsistence hunts for the other 4 Alaskan stocks of beluga whales. These groups set harvest limits and other requirements to ensure conservation of the species.

Regulatory Overview

On March 3, 1999, we received two petitions to list the Cook Inlet population of beluga whales as endangered under the ESA. The petitioners requested that we issue an emergency listing under section 4(b)(7) of the ESA, designate critical habitat for Cook Inlet beluga whales, and take immediate action to implement rulemaking to regulate the harvest of these whales.

In May 2000, we designated Cook Inlet beluga whales as depleted under the Marine Mammal Protection Act. However, at that time, the agency determined that the Cook Inlet beluga whale population was not threatened or endangered under the ESA. But, because this stock did not show significant evidence of recovery thereafter, we initiated a second Status Review in the spring of 2006.

In April 20, 2006, the Trustees for Alaska petitioned us to list the Cook Inlet beluga whale as threatened or endangered under the ESA. We evaluated the petition and conducted a status review.

In October 2008, we determined that beluga whales in the Cook Inlet needed protection under the ESA, and, on October 22, 2008, listed the population as endangered.

In April 2009, we solicited public comments and information in an Advance Notice of Proposed Rulemaking to designate critical habitat for Cook Inlet beluga whales. In December 2009, we proposed critical habitat [pdf] for Cook Inlet beluga whales. In April 2011, we designated critical habitat [pdf] in the Cook Inlet.

There are no regulatory actions for the other 4 Alaskan stocks of beluga whales.

Taxonomy

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Family: Monodontidae
Genus: Delphinapterus
Species: leucas

References:

Cool/Gross/Weird:

  • Belugas are known as the “canaries of the sea” because of the vast range of sounds they produce.
  • The name beluga comes from the Russian word “bielo” for white.
  • Belugas have flexible necks, allowing them to move their heads separate from their bodies.
  • Two layers of blubber.
  • Skin is thick enough to make leather.
  • They can crinkle and change the shape of their melon by moving air around in the sinuses.
  • Slow swimmers, but can maneuver around tight spaces as well as swimming backwards.
  • They appear to be smiling.
  • They don’t breach or lobtail like most other whales and dolphins.

-TSF-

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