The beluga whale (; Delphinapterus leucas) is an Arctic and sub-Arctic cetacean. It is one of two living members of the family Monodontidae, along with the narwhal, and the only member of the genus Delphinapterus. It is also known as the white whale, as it is the only cetacean to regularly occur with this colour; the sea canary, due to its high-pitched calls; and the melonhead, though that more commonly refers to the melon-headed whale, which is an oceanic dolphin.
The beluga is adapted to life in the Arctic, with anatomical and physiological characteristics that differentiate it from other cetaceans. Amongst these are its all-white colour and the absence of a dorsal fin, which allows it to swim under ice with ease. It possesses a distinctive protuberance at the front of its head which houses an echolocation organ called the melon, which in this species is large and deformable. The beluga's body size is between that of a dolphin and a true whale, with males growing up to long and weighing up to . This whale has a stocky body. Like many cetaceans, a large percentage of its weight is blubber (subcutaneous fat). Its sense of hearing is highly developed and its echolocation allows it to move about and find breathing holes under sheet ice.
Belugas are gregarious and form groups of 10 animals on average, although during the summer, they can gather in the hundreds or even thousands in Estuary and shallow coastal areas. They are slow swimmers, but can dive to below the surface. They are opportunistic feeders and their diets vary according to their locations and the season. The majority of belugas live in the Arctic Ocean and the seas and coasts around North America, Russia, and Greenland; their worldwide population is thought to number around 200,000. They are Animal migration and the majority of groups spend the winter around the Arctic ice cap; when the sea ice melts in summer, they move to warmer river estuaries and coastal areas. Some populations are sedentary and do not migrate over great distances during the year.
The native peoples of North America and Russia have hunted belugas for many centuries. They were also hunted by non-natives during the 19th century and part of the 20th century. Hunting of belugas is not controlled by the International Whaling Commission, and each country has developed its own regulations in different years. Currently, some Inuit in Canada and Greenland, Alaska Native groups and Russians are allowed to hunt belugas for consumption as well as for sale, as aboriginal whaling is excluded from the International Whaling Commission 1986 moratorium on hunting. The numbers have dropped substantially in Russia and Greenland, but not in Alaska and Canada. Other threats include natural predators ( and ), contamination of rivers (as with polychlorinated biphenyl (PCBs) which bioaccumulate up the food chain), climate change and infectious diseases. The beluga was placed on the International Union for Conservation of Nature's Red List in 2008 as being "near threatened"; the subpopulation from the Cook Inlet in Alaska is considered critically endangered and is under the protection of the United States' Endangered Species Act. Of all seven extant Canadian beluga populations, those inhabiting eastern Hudson Bay, Ungava Bay, and the St. Lawrence River are listed as endangered.
Belugas are one of the most commonly kept cetaceans in captivity and are housed in aquariums, and wildlife parks in North America, Europe and Asia. They are considered charismatic because of their docile demeanour and characteristic smile, communicative nature, and supple, graceful movement.
The name of the genus, Delphinapterus, means "dolphin without fin" (from the Greek δελφίν ( delphin), dolphin and απτερος ( apteros), wingless) and the species name leucas means "white" (from the Greek λευκας ( leukas), white).
The whale is also colloquially known as the "sea canary" on account of its high-pitched squeaks, squeals, clucks, and whistles. A Japanese researcher claimed that he taught a beluga to "talk" by using these sounds to identify three different objects, offering hope that humans may one day be able to communicate effectively with sea mammals. A similar observation has been made by Canadian researchers, where a beluga which died in 2007 "talked" when he was still a subadult. Another example is NOC, a beluga whale that could mimic the rhythm and tone of human language. Beluga whales in the wild have been reported to imitate human voices.
The beluga's earliest known distinctive ancestors include the prehistoric Denebola brachycephala from the late Miocene epoch (9–10 million years ago), and Bohaskaia monodontoides, from the early Pliocene (3–5 million years ago). Fossil evidence from Baja California and Virginia indicate the family once inhabited warmer waters. A fossil of the monodontid Casatia thermophila, from five million years ago, provides the strongest evidence that monodontids once inhabited warmer waters, as the fossil was found alongside fossils of tropical species such as bull and tiger sharks.
The fossil record also indicates that, in comparatively recent times, the beluga's range varied with that of the polar ice packs expanding during and contracting when the ice retreated. Counter-evidence to this theory comes from the finding in 1849 of fossilised beluga bones in Vermont in the United States, from the Atlantic Ocean. The bones were discovered during construction of the first railroad between Rutland and Burlington in Vermont, when workers unearthed the bones of a mysterious animal in Charlotte. Buried nearly below the surface in a thick blue clay, these bones were unlike those of any animal previously discovered in Vermont. Experts identified the bones as those of a beluga. Because Charlotte is over from the nearest ocean, early naturalists were at a loss to explain the presence of the bones of a marine mammal buried beneath the fields of rural Vermont.
The remains were found to be preserved in the sediments of the Champlain Sea, an extension of the Atlantic Ocean within the continent resulting from the rise in sea level at the end of the ice ages some 12,000 years ago. Today, the Charlotte whale is the official Vermont State Fossil (making Vermont the only state whose official fossil is that of a still extant animal).
Individuals of both sexes reach their maximum size by the time they are 10 years old. The beluga's body shape is stocky and fusiform (cone-shaped with the point facing backwards), and they frequently have folds of fat, particularly along the ventral surface. Between 40% and 50% of their body weight is fat, which is a higher proportion than for cetaceans that do not inhabit the Arctic, where fat only represents 30% of body weight. The fat forms a layer that covers all of the body except the head, and it can be up to thick. It acts as insulation in waters with temperatures between 0 and 18 °C, as well as being an important reserve during periods without food.
Unlike many dolphins and whales, the seven in the neck are not fused together, allowing the animal to turn its head laterally without needing to rotate its body. This gives the head a lateral manoeuvrability that allows an improved field of view and movement and helps in catching prey and evading predators in deep water. The rostrum has about eight to ten small, blunt and slightly curved teeth on each side of the jaw and a total of 36 to 40 teeth. Belugas do not use their teeth to chew, but for catching hold of their prey; they then tear them up and swallow them nearly whole.
Belugas only have a single spiracle, which is located on the top of the head behind the melon, and has a muscular covering, allowing it to be completely sealed. Under normal conditions, the spiracle is closed and an animal must contract the muscular covering to open the spiracle. A beluga's thyroid gland is larger than that of terrestrial —weighing three times more than that of a horse—which helps it to maintain a greater metabolism during the summer when it lives in river estuaries. It is the marine cetacean that most frequently develops Hyperplasia and Neoplasia lesions of the thyroid.
Belugas have a dorsal ridge, rather than a dorsal fin. The absence of the dorsal fin is reflected in the genus name of the species— apterus the Greek language word for "wingless". The evolutionary preference for a dorsal ridge rather than a fin is believed to be an adaptation to under-ice conditions, or possibly as a way of preserving heat. The crest is hard and, along with the head, can be used to open holes in ice up to thick.
Belugas are able to see within and outside of water, but their vision is relatively poor when compared to dolphins. Their eyes are especially adapted to seeing under water, although when they come into contact with the air, the crystalline lens and the cornea adjust to overcome the associated myopia (the range of vision under water is short). A beluga's retina has cones and rods, which also suggests they can see in low light. The presence of cone cells indicates they can see colours, although this suggestion has not been confirmed. Glands located in the medial corner of their eyes secrete an oily, gelatinous substance that lubricates the eye and helps flush out foreign bodies. This substance forms a film that protects the cornea and the conjunctiva from pathogenic organisms.
Studies on captive animals show they seek frequent physical contact with other belugas. Areas in the mouth have been found that could act as for different tastes, and they can detect the presence of blood in water, which causes them to react immediately by displaying typical alarm behaviour. Like the other toothed whales, their brains lack and olfactory nerves, which suggests they do not have a sense of smell.
They are cooperative animals and frequently hunt in coordinated groups. The animals in a pod are very sociable and often chase each other as if they are playing or fighting, and they often rub against each other. Often individuals will surface and dive together in a synchronized manner, in a behavior known as milling.
In captivity, they can be seen to be constantly playing, vocalising and swimming around each other. In one case, one whale blew bubbles, while the other one popped them. There have also been reports of beluga whales copying and imitating one another, similar to a game of Simon-says. There have also been reports of them displaying physical affection, via mouth to mouth contact. They also show a great deal of curiosity towards humans and frequently approach the windows in the tanks to observe them.
Belugas also show a great degree of curiosity towards humans in the wild, and frequently swim alongside boats. They also play with objects they find in the water; in the wild, they do this with wood, plants, dead fish and bubbles they have created. During the breeding season, adults have been observed carrying objects such as plants, nets, and even the skeleton of a dead reindeer on their heads and backs. Captive females have also been observed displaying this behavior, carrying items such as floats and buoys, after they have lost a calf. Experts consider this interaction with the objects to be a substitute behavior.
In captivity, mothering behavior among belugas depends on the individual. Some mothers are extremely attentive while other mothers are so blasé, that they have actually lost their calves. In aquaria, there have been cases where dominant females have stolen calves from mothers, particularly if they have lost a calf or if they are pregnant. After giving birth, dominant females will return the calf back to their mother. Additionally, male calves will temporarily leave their mothers to interact with an adult male who can serve as a role model for the calf, before they return to their mothers. Male calves are also frequently seen interacting with each other.
These animals usually only dive to depths to , although they are capable of diving to greater depths. Individual captive animals have been recorded at depths between 400 and 647 m below sea level, while animals in the wild have been recorded as diving to a depth of more than 700 m, with the greatest recorded depth being over 900 m. A dive normally lasts 3 to 5 minutes, but can last up to over 20 minutes. In the shallower water of the estuaries, a diving session may last around two minutes; the sequence consists of five or six rapid, shallow dives followed by a deeper dive lasting up to one minute. The average number of dives per day varies between 31 and 51.
All cetaceans, including belugas, have physiological adaptations designed to conserve oxygen while they are under water. During a dive, these animals will reduce their heart rate from 100 beats a minute to between 12 and 20. Blood flow is diverted away from certain tissues and organs and towards the brain, heart and , which require a constant oxygen supply. The amount of oxygen dissolved in the blood is 5.5%, which is greater than that found in land-based mammals and is similar to that of (a diving marine mammal). One study found a female beluga had 16.5 L of oxygen dissolved in her blood. Lastly, the beluga's muscles contain high levels of the protein myoglobin, which stores oxygen in muscle. Myoglobin concentrations in belugas are several times greater than for terrestrial mammals, which help prevent oxygen deficiency during dives.
Beluga whales often accompany , for curiosity and to secure polynya feasibility to breathe as bowheads are capable of breaking through ice from underwater by headbutting.
The diet of Alaskan belugas is quite diverse and varies depending on season and migratory behavior. Belugas in the Beaufort Sea mainly feed on staghorn and shorthorn sculpin, walleye pollock, Arctic cod, saffron cod and sand lance. Shrimp are the most common invertebrate eaten, with octopus, amphipods and Echiura being other sources of invertebrate prey. The most common prey species for belugas in the Eastern Chukchi Sea appears to be shrimp, echiurid worms, cephalopods and polychaetes. The largest prey item consumed by beluga whales in the Eastern Chukchi Sea seems to be saffron cod. Beluga whales in the Eastern Bering Sea feed on a variety of fish species including saffron cod, rainbow smelt, walleye pollock, Pacific salmon, Pacific herring and several species of flounder and sculpin. The primary invertebrate consumed is shrimp. The primary prey item in regard to fish species for belugas in Bristol Bay appears to be the five species of salmon, with sockeye being the most prevalent. Smelt is also another common fish family eaten by belugas in this region. Shrimp is the most prevalent invertebrate prey item. The most common prey items for belugas in Cook Inlet appear to be salmon, cod and smelt.
Animals in captivity eat 2.5% to 3.0% of their body weight per day, which equates to . Like their wild counterparts, captive belugas were found to eat less in the fall.
Foraging on the seabed typically takes place at depths between , although they can dive to depths of in search of food. Their flexible necks provide a wide range of movement while they are searching for food on the ocean floor. Some animals have been observed to suck up water and then forcefully expel it to uncover their prey hidden in the silt on the seabed. As their Tooth are neither large nor sharp, belugas must use suction to bring their prey into their mouths; it also means their prey has to be consumed whole, which in turn means it cannot be too large or the belugas run the risk of it getting stuck in their throats. They also join into coordinated groups of five or more to feed on shoals of fish by steering the fish into shallow water, where the belugas then attack them. For example, in the estuary of the Amur River, where they mainly feed on salmon, groups of six or eight individuals join to surround a shoal of fish and prevent their escape. Individuals then take turns feeding on the fish.
Female belugas typically give birth to one calf every three years. Most mating occurs from February to May, but some occurs at other times of year. The beluga may have delayed implantation. Gestation has been estimated to last 12.0 to 14.5 months, but information derived from captive females suggests a period up to 475 days (15.8 months). During the mating season, the testes of belugas double in weight. Testosterone levels increase, but seems to be independent of copulation. Copulation typically takes place between 3 and 4 AM.
Calves are born over a protracted period that varies by location. In the Canadian Arctic, calves are born between March and September, while in Hudson Bay, the peak calving period is in late June, and in Cumberland Sound, most calves are born from late July to early August. Births usually take place in bays or estuaries where the water is between 10 and 15 °C. Newborns are about long, weigh about , and are grey in colour. They are able to swim alongside their mothers immediately after birth. The newborn calves nurse under water and initiate lactation a few hours after birth; thereafter, they feed at intervals around an hour. Studies of captive females have indicated their milk composition varies between individuals and with the stage of lactation; it has an average content of 28% fat, 11% protein, 60.3% water, and less than 1% residual solids. The milk contains about 92 calories per ounce.
The calves remain dependent on their mothers for nursing for the first year, when their teeth appear. After this, they start to supplement their diets with shrimp and small fish. The majority of the calves continue nursing until they are 20 months old, although occasionally lactation can continue for more than two years, and lactational anoestrus may not occur. Alloparenting (care by females different from the mother) has been observed in captive belugas, including spontaneous and long-term milk production. This suggests this behaviour, which is also seen in other mammals, may be present in belugas in the wild.
Hybrids have been documented between the beluga and the narwhal (specifically offspring conceived by a beluga father and a narwhal mother), as one, perhaps even as many as three, such hybrids were killed and harvested during a sustenance hunt. Whether or not these hybrids could breed remains unknown. The unusual dentition seen in the single remaining skull indicates the hybrid hunted on the seabed, much as walruses do, indicating feeding habits different from those of either parent species.
Some evidence indicates that belugas are highly sensitive to noise produced by humans. In one study, the maximum frequencies produced by an individual located in San Diego Bay, California, were between 40 and 60 kHz. The same individual produced sounds with a maximum frequency of 100 to 120 kHz when transferred to Kaneohe Bay in Hawaii. The difference in frequencies is thought to be a response to the difference in environmental noise in the two areas. In special circumstances, beluga whale sounds have been reported to resemble human speech.
These animals communicate using sounds of high frequency; their calls can sound like bird songs, so belugas were nicknamed "canaries of the sea". Like the other toothed whales, belugas do not possess Vocal folds and the sounds are probably produced by the movement of air between the nasal sacks, which are located near to the blowhole.
Belugas are among the most vocal cetaceans. They use their vocalisations for echolocation, during mating and for communication. They possess a large repertoire, emitting up to 11 different sounds, such as cackles, whistles, trills and squawks. They make sounds by grinding their teeth or splashing, but they rarely use body language.
There is debate as to whether cetacean vocalizations can constitute a language. A study conducted in 2015 determined that European beluga signals share physical features comparable to vowels. These sounds were found to be stable throughout time, but varied among different geographical locations. The further away the populations were from each other, the more varied the sounds were in relation to one another.
The migration season is relatively predictable, as it is basically determined by the amount of daylight and not by other variable physical or biological factors, such as the condition of the sea ice. Vagrants may travel further south to areas such as Ireland and Scotland waters, the islands of Orkney Islands and Hebrides, and to Hokkaido waters. There had been several vagrant individuals that have demonstrated seasonal residencies at Muroran, of Muroran Renaissance and a unique whale were used to return annually to areas adjacent to Shibetsu in Nemuro Strait in the 2000s. On rarer occasions, individuals of vagrancy can reach the Korean Peninsula. A few other individuals have been confirmed to return to the coasts of Hokkaido, and one particular individual became a resident in of Lake Notoro since in 2014.
Some populations are not migratory and certain resident groups will stay in well-defined areas, such as in Cook Inlet, the estuary of the Saint Lawrence River and Cumberland Sound. The population in Cook Inlet stays in the waters furthest inside the inlet during the summer until the end of autumn. Then during the winter, they disperse to the deeper water in the center of the inlet, but without completely leaving it.
In April, the animals that spend the winter in the center and southwest of the Bering Sea move to the north coast of Alaska and the east coast of Russia. The populations living in the Ungava Bay and the eastern and western sides of Hudson Bay overwinter together beneath the sea ice in Hudson Strait. Whales in James Bay that spend winter months within the basin, could be a distinct group from those in Hudson Bay. The populations of the White Sea, the Kara Sea and the Laptev Sea overwinter in the Barents Sea. In the spring, the groups separate and migrate to their respective summer sites.
In coastal areas, they can be found in , , , and shallow waters in the Arctic Ocean that are continuously lit by sunlight. They are also often seen during the summer in river estuaries, where they feed, socialize and give birth to young. These waters usually have a temperature between 8 and 10 °C. The of Cook Inlet in Alaska are a popular location for these animals to spend the first few months of summer. In the eastern Beaufort Sea, female belugas with their young and immature males prefer the open waters close to land, while the adult males live in waters covered by ice near the Canadian Arctic Archipelago. The younger males and females with slightly older young can be found nearer to the ice shelf. Generally, the use of different habitats in summer reflects differences in feeding habits, risk from predators and reproductive factors for each of the subpopulations.
The Yakutat Bay belugas are not considered to be a true stock because they have only been present in these waters since the 1980s, and are believed to be of Cook Inlet origin. It is estimated that less than 20 whales inhabit the bay year-round. Overall the beluga population is estimated to be 150,000–200,000 animals.
Hunters in Hudson's Bay rarely eat the meat. They give a little to dogs, and leave the rest for wild animals. Other areas may dry the meat for later consumption by humans. In Greenland the skin (muktuk) is sold commercially to fish factories, and in Canada to other communities. An average of one or two vertebrae and one or two teeth per beluga are carved and sold. One estimate of the annual gross value received from Beluga hunts in Hudson Bay in 2013 was for 190 belugas, or per beluga. However, the net income, after subtracting costs in time and equipment, was a loss of per person. Hunts receive subsidies, but they continue as a tradition, rather than for the money, and the economic analysis noted that whale watching may be an alternate revenue source. Of the gross income, was for skin and meat, to replace beef, pork and chickens which would otherwise be bought. was received for carved vertebrae and teeth.
Russia now harvests 5 to 30 belugas per year for meat and captures an additional 20 to 30 per year for live export to Chinese aquarium. However, in 2018, 100 were illegally captured for live export.
Previous levels of commercial whaling have put the species in danger of extinction in areas such as Cook Inlet, Ungava Bay, the St. Lawrence River and western Greenland. Continued hunting by the native peoples may mean some populations will continue to decline. Northern Canadian sites are the focus of discussions between local communities and the Canadian government, with the objective of permitting sustainable hunting that does not put the species at risk of extinction.
The total amount of landed (defined as belugas successfully hunted and retrieved) belugas averages 275 in regard to the Bering, Chukchi and Beaufort stocks from 1987 to 2006. The average annual landed harvest of belugas in the Beaufort Sea consisted of 39 individuals while the Chukchi harvest averaged 62 individuals. Bristol bay's annual average landed harvest was 17 while the Bering Sea's was 152. Statistical studies have demonstrated that subsistence hunting in Alaska did not significantly impact the population of the Alaskan beluga whale stocks. The number of belugas struck and lost did not seem to profoundly impact Chukchi and Bering Sea belugas.
Russia had large hunts, peaking in the 1930s at 4,000 per year and the 1960s at 7,000 per year, for a total of 86,000 from 1915 to 2014. Canada hunted a total of 54,000 from 1731 to 1970. Between 1868 and 1911, Scotland and American whalers killed more than 20,000 belugas in Lancaster Sound and Davis Strait.
During the 1920s, fishermen in the Saint Lawrence River estuary considered belugas to be a threat to the fishing industry, as they eat large quantities of cod, salmon, tuna and other fish caught by the local fishermen. The presence of belugas in the estuary was, therefore, considered to be undesirable; in 1928, the Government of Quebec offered a reward of 15 dollars for each dead beluga. The Quebec Department of Fisheries launched a study into the influence of these cetaceans on local fish populations in 1938. The unrestricted killing of belugas continued into the 1950s, when the supposed voracity of the belugas was found to be overestimated and did not adversely affect fish populations. L'Isle-aux-Coudres is the setting for the classic 1963 National Film Board of Canada documentary Pour la suite du monde, which depicts a one-off resurrection of the beluga hunt; one animal is caught live, and transported by truck to an aquarium in the big city. The method of capture is akin to dolphin drive hunting.
Orca hunt and eat both young and adult belugas. They live in all the seas of the world and share the same habitat as belugas in the sub-Arctic region. Attacks on belugas by killer whales have been reported in the waters of Greenland, Russia, Canada and Alaska. A number of killings have been recorded in Cook Inlet, and experts are concerned the predation by killer whales will impede the recovery of this sub-population, which has already been badly depleted by hunting. The killer whales arrive at the beginning of August, but the belugas are occasionally able to hear their presence and evade them. The groups near to or under the sea ice have a degree of protection, as the killer whale's large dorsal fin, up to 2 m in length, impedes their movement under the ice and does not allow them to get sufficiently close to the breathing holes in the ice. Beluga whale behavior under killer whale predation makes them vulnerable to hunters. When killer whales are present, large numbers of beluga whales congregate in the shallows for protection, which allows them to be hunted in droves.
Human pollution can be a threat to belugas' health when they congregate in river estuaries. Chemical substances such as DDT and heavy metals such as lead, mercury and cadmium have been found in individuals of the Saint Lawrence River population. Local beluga carcasses contain so many contaminants, they are treated as toxic waste. Levels of polychlorinated biphenyls between 240 and 800 ppm have been found in belugas' , liver and , with the highest levels found in males. These levels are significantly greater than those found in Arctic populations. These substances have a proven adverse effect on these cetaceans, as they cause , reproductive diseases and the deterioration of the immune system, making individuals more susceptible to , , , and bacterial . Although the populations that inhabit the river estuaries run the greatest risk of contamination, high levels of zinc, cadmium, mercury and selenium have also been found in the muscles, livers and of animals that live in the open sea. The concentration of mercury in Beaufort Sea belugas tripled from the 1980s to the 1990s, but has decreased in Beaufort belugas as of the 21st century, possibly due to changes in dietary preference. Larger body sized belugas tend to have more mercury than smaller sized belugas, because they spend more time offshore, hunting prey such as cod and shrimp, which have more mercury.
From a sample of 129 beluga adults from the Saint Lawrence River examined between 1983 and 1999, a total of 27% had suffered cancer. This is a higher percentage than that documented for other populations of this species and is much higher than for other cetaceans and for the majority of terrestrial mammals; in fact, the rate is only comparable to the levels found in humans and some domesticated animals. For example, the rate of intestinal cancer in the sample is much higher than for humans. This condition is thought to be directly related to environmental contamination, in this case by polycyclic aromatic hydrocarbons, and coincides with the high incidence of this disease in humans residing in the area. The prevalence of tumours suggests the contaminants identified in the animals that inhabit the estuary are having a direct carcinogenic effect or they are at least causing an immunological deterioration that is reducing the inhabitants' resistance to the disease.
Indirect human disturbance may also be a threat. While some populations tolerate small boats, most actively try to avoid ships. Whale-watching has become a booming activity in the St. Lawrence and Churchill River areas, and acoustic contamination from this activity appears to have an effect on belugas. For example, a correlation appears to exist between the passage of belugas across the mouth of the Saguenay River, which has decreased by 60%, and the increase in the use of recreational motorboats in the area. A dramatic decrease has also been recorded in the number of calls between animals (decreasing from 3.4 to 10.5 calls/min to 0 or <1) after exposure to the noise produced by ships, the effect being most persistent and pronounced with larger ships such as Ferry than with smaller boats. Belugas can detect the presence of large ships (for example ) up to 50 km away, and they move rapidly in the opposite direction or perpendicular to the ship following the edge of the sea ice for distances of up to 80 km to avoid them. The presence of shipping produces avoidance behaviour, causing deeper dives for feeding, the break-up of groups, and asynchrony in dives.
Papillomaviridae, Herpesviridae, and encephalitis caused by the protozoan Sarcocystis have been found in belugas in the Saint Lawrence River. Cases have been recorded of ciliate protozoa colonising the spiracle of certain individuals, but they are not thought to be pathogens or are not very harmful. The bacterium Erysipelothrix rhusiopathiae, which probably comes from eating infected fish, poses a threat to belugas kept in captivity, causing anorexia and dermal plaques and that can lead to sepsis. This condition can cause death if it is not diagnosed and treated in time with such as ciprofloxacin. A study of infections caused by parasitic worms in a number of individuals of both sexes found the presence of larvae from a species from the genus Contracaecum in their and , Anisakis simplex in their stomachs, Pharurus pallasii in their ear canals, Hadwenius seymouri in their intestines and Leucasiella arctica in their rectums.
To provide some enrichment while in captivity, aquaria train belugas to perform behaviours for the public and for medical exams, such as blood draws, ultrasound, providing toys, and allowing the public to play recorded or live music.
Between 1960 and 1992, the United States Navy carried out a program that included the study of ' abilities with echolocation, with the objective of improving the detection of underwater objects. The program started with dolphins, but a large number of belugas were also used from 1975 onwards. The program included training them to carry equipment and material to divers working under water, the location of lost objects, surveillance of ships and , and underwater monitoring using cameras held in their mouths. A similar program was implemented by the Soviet Navy during the Cold War, in which belugas were also trained for antiNaval mine operations in Arctic waters. It is possible this program continues within the Russian Navy, as on April 24, 2019, a Hvaldimir was found by fishermen near the Norwegian island of Ingøya.
Belugas released from captivity have difficulties adapting to life in the wild, but if not fed by humans they may have a chance to join a group of wild belugas and learn to feed themselves, according to Audun Rikardsen of the University of Tromsø.
In 2019, a sanctuary in Iceland was established for two belugas, Little White and Little Grey, that retired from a marine park in China. The Sea Life Trust Beluga Whale Sanctuary was created with support from Merlin Entertainments and Whale and Dolphin Conservation (WDC). Merlin bought the park in 2012, as part of an Australian chain, and it is one of their largest aquaria. Merlin has a policy against captive cetaceans, so they sponsored a 32,000-square-metre sea pen as a sanctuary. The 12-year-old belugas, caught in Russia and raised in captivity, do not know how to live in the wild. The cost is variously listed as ISK 3,000,000 (US$24,000) or US$27,000,000. Merlin was owned until 2015 by Blackstone Group, which also owned SeaWorld until selling its last stake in 2017 to a Chinese company which will use SeaWorld's expertise to expand in China; SeaWorld still keeps belugas in captivity.
Belugas are displayed across North America, Europe and Asia. As of 2006, 58 belugas were held in captivity in Canada and the United States, and 42 deaths in US captivity had been reported up to that time. A single specimen costs up to US$100,000, although the price has now dropped to US$70,000. Article says belugas cost USD 70,000 or 60,000, while orcas cost USD 7 million, while another article says orcas cost USD 1 million (RUB 67 million) As of January 2018, according to the nonprofit Ceta Base, which tracks belugas and dolphins under human care, there were 81 captive belugas in Canada and the United States, and unknown numbers in the rest of the world. The beluga's popularity with visitors reflects its attractive colour and its range of facial expressions. The latter is possible because while most cetacean "smiles" are fixed, the extra movement afforded by the beluga's unfused cervical vertebrae allows a greater range of apparent expression.
Most belugas found in aquaria are caught in the wild, as captive-breeding programs have not had much success so far. For example, despite best efforts, as of 2010, only two male whales had been successfully used as stud animals in the Association of Zoos and Aquariums beluga population, Nanuq at SeaWorld San Diego and Naluark at the Shedd Aquarium in Chicago, US. Nanuq has fathered 10 calves, five of which survived birth. Naluark at Shedd Aquarium has fathered four living offspring. Naluark was relocated to the Mystic Aquarium in the hope that he would breed with two of their females, but he did not, and in 2016 he was moved to SeaWorld Orlando. The first beluga calf born in captivity in Europe was born in L'Oceanogràfic marine park in Valencia, Spain, in November 2006. However, the calf died 25 days later after suffering Metabolism complications, infections and not being able to feed properly. A second calf was born on 16 November 2016, and was successfully maintained by artificial feeding based on enriched milk.
In 2009 during a free-diving competition in a tank of icy water in Harbin, China, a captive beluga brought a cramp-paralysed diver from the bottom of the pool up to the surface by holding her foot in its mouth, saving the diver's life.
Films which have publicised issues of beluga welfare include Born to Be Free, Sonic Sea, and Vancouver Aquarium Uncovered.
However, the boats' presence poses a threat, as it distracts them from important activities such as feeding, social interaction and reproduction. In addition, the noise produced by the motors has an adverse effect on their auditory function and reduces their ability to detect their prey, communicate and navigate. To protect these marine animals during whale-watching activities, the US National Oceanic and Atmospheric Administration has published a "Guide for observing marine life". The guide recommends boats carrying the whale watchers keep their distance from the cetaceans and it expressly prohibits chasing, harassing, obstructing, touching, or feeding them.
Some regular migrations do occur into Russian EEZ of Sea of Japan such as to Rudnaya Bay, where diving with wild belugas became a less-known but popular attraction.
On 25 September 2018, a beluga was sighted in the Thames Estuary and near towns along the Kent side of the Thames, being nicknamed Benny by newspapers. The whale, who was noticed by conservationists to be traveling alone, appeared to be separated from the rest of its group, and is thought to be a lost individual. Subsequent sightings were reported on the following day, and continued into 2019, when local experts concluded that Benny had left the estuary.
On 13 May 2021, two beluga whales were sighted in waters around Prince Edward Island, Atlantic Canada. One whale entered the Charlottetown Harbour and travelled up the Hillsborough River to Mount Stewart, Prince Edward Island. As of 30 May the whale was still sighted in the area.
In August 2022, a beluga was found on the river Seine, France.
There are about 21 sub-populations of beluga whales and it is estimated that 200,000 individuals still exist, which are listed as Least Concern on the IUCN Red List. However, the nonmigratory Cook Inlet sub-population off the Gulf of Alaska is a separate sub-population that is listed as "critically endangered" by the IUCN as of 2006 and as "endangered" under the Endangered Species Act as of October 2008. This was primarily due to unregulated overharvesting of beluga whales prior to 1998. The population has remained relatively consistent, though the reported harvest has been small. As of 2016, the estimated abundance of the endangered Cook Inlet population was 293 individuals. The most recent estimate in 2018 by NOAA Fisheries suggested that the population declined to 279 individuals.
Despite beluga whales not being threatened overall, sub-populations are being listed as critically endangered and are facing increased mortality from human actions. For example, even though commercial hunting is now banned due to the Marine Mammal Protection Act, beluga whales are still being hunted to preserve the livelihood of native Alaskan communities. The IUCN and NOAA Fisheries cite habitat degradation, oil and gas drilling, underwater noise, harvesting for consumption and climate change as threats to the prolonged survival of beluga whale sub-populations.
Beluga whale populations are currently being harvested at levels which are not sustainable and it is difficult for those harvesting beluga whales to know which sub-population they are from. Because there is little protection of sub-populations, harvest will need to be managed to ensure sub-populations will survive long into the future to discover the importance of their migratory patterns and habitat use.
Beluga whales, like most other arctic species, are being faced with alteration of their habitat due to climate change and melting arctic ice. Changes in sea-ice has resulted in changes in the area used by Chukchi belugas, since belugas spent less time in close proximity to the ice edge in comparison to previous years. Additionally, Chukchi Sea belugas spent a prolonged amount of time in Barrow Canyon on the Beaufort Sea side in October. Chukchi sea belugas also appear to be spending more time in deeper water presently, as opposed to the 1990s. Belugas also seemed to be taking longer and deeper dives. A hypothesis as to why this might be the case is an up-welling of rich Atlantic water in the Beaufort Sea may result in concentrated prey items like Arctic cod. The fall migration of Chukchi belugas is later, although summer and fall habitat selection has not changed. Fall migration of Chukchi belugas appears to be correlated with Beaufort Sea freeze up.
It is hypothesized that beluga whales utilize ice as protection from killer whale predation or for feeding on schools of fish. Killer whales can penetrate further into the Arctic and remain in arctic waters for a longer period of time due to reductions in sea ice. For example, residents in Kotzebue, have reported that killer whales have been sighted more frequently in Kotzebue Sound.
As annual ice cover declines, humans may gain access and disrupt beluga whale habitats. For example, the number of vessels in the Arctic for gas and oil exploration, fishing, and commercial shipping has already increased and a continuous trend may lead to higher risks of injuries and deaths for beluga whales.
In addition, it is possible that beluga whales may face by an increased risk of entrapment from leads and cracks freezing, due to the erratic nature of climate change. Abrupt changes in weather can cause these leads and cracks to freeze ultimately causing the whales to die of suffocation. An increase in urbanization will likely lead to higher concentrations of toxic pollutants in the blubber of beluga whales since they are at the top of the food chain and are affected by bio-accumulation. Loss of sea ice and a change in ocean temperatures may also affect the distribution and composition of prey or affect their competition. There is also some evidence that climate change can affect males and females differently. Since 1983, belugas have been increasingly scarce in Kotzebue sound. However, in 2007, several hundred whales were spotted in the sound, with over 90% of the whales being male. However, more research needs to be conducted to understand how climate change affects beluga whale sex aggregation.
To prevent hunting, belugas are protected under the 1986 International Moratorium on Commercial Whaling; however, hunting of small numbers of belugas is still allowed. Since it is very difficult to know the exact population of belugas because their habitats include inland waters away from the ocean, they easily come in contact with oil and gas development centres. To prevent whales from coming in contact with industrial waste, the Alaskan and Canadian governments are relocating sites where whales and waste come in contact.
The beluga whale is listed on appendix II of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). It is listed on appendix II as it has an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements. All toothed whales are protected under the CITES that was signed in 1973 to regulate the international import and export of certain species.
The isolated beluga population in the Saint Lawrence River has been legally protected since 1983. In 1988 Canadian Department of Fisheries and Oceans and Environment Canada, a governmental agency that supervises national parks, implemented the Saint Lawrence Action Plan with the aim of reducing industrial contamination by 90% by 1993; as of 1992, the emissions had been reduced by 59%. The population of the St. Lawrence belugas decreased from 10,000 in 1885 to around 1,000 in the 1980 and around 900 in 2012.
Managed care facilities in North America have been able to work cooperatively to build upon the research of beluga whale reproduction and have made remarkable advances. Using operant conditioning, these facilities have trained beluga whales for voluntary biological sampling and examinations. Blood, urine, and blow samples have all been collected for longitudinal hormone monitoring studies.
In addition, beluga whales have undergone semen collection, body temperature data collection, reproductive tract examinations via transabdominal ultrasound, and endoscopic exams. With new technology, the reproductive characteristics of both the female and male beluga whale have been accurately described and has benefited captive breeding programs globally.
As more research is done, the management of beluga whales in managed care facilities can be greatly improved and may even help develop other cetacean breeding and contraceptive programs, such as that of the bottlenose dolphin. Through fetal health and gestation monitoring, facilities can be more equipped to deal with pregnant animals as well. While training has been done to collect beluga whale semen, only few facilities have been able to successfully do so as both saltwater and urine contamination need to be avoided. Improvement of this process will help increase the success of captive breeding programs.
The children's singer Raffi released an album called Baby Beluga in 1980. The album starts with the sound of whales communicating, and includes songs representing the ocean and whales playing. The song "Baby Beluga" was composed after Raffi saw a recently born beluga calf in Vancouver Aquarium.
The fuselage design of the Airbus Beluga, one of the world's biggest cargo planes, is very similar to that of a beluga. It was originally called the Super Transporter, but the nickname Beluga became more popular and was then officially adopted. The company paints the 2019 Beluga XL version to emphasize the plane's similarity to the Beluga whale.
In the 2016 Disney/Pixar animated film Finding Dory, the sequel to Finding Nemo (2003), the character Bailey is a beluga whale and its echolocation abilities are a significant part of the plot.
Description
Longevity
Size
Colour
Head and neck
Fins
Senses
Behaviour
Social structure and play
Swimming and diving
Diet
Reproduction
Communication and echolocation
Distribution
Migration
Habitat
Population
Threats
Hunting
Present
Past
Beluga catches by location
Annual table showing the number of belugas caught in Canada, Russia, Greenland and Alaska each year, from 2016 back to 1954
!scope="col" Beaufort Sea, Mackenzie, Paulatuk, Ulukhaktok, Canada
!scope="col" Nunavut, Canada
!scope="col" Nunavik, Quebec, Canada
!scope="col" Western Arctic, Russia, hunted for meat
!scope="col" Eastern Arctic, Russia, hunted for meat
!scope="col" Sea of Okhotsk, Russia, hunted for meat
!scope="col" All areas of Russia, live export
!scope="col" Year
!scope="col" Canada total
!scope="col" Greenland
!scope="col" USSR+ Russia total
!scope="col" US (Alaska)
!scope="col" World total, incomplete
!scope="col" Lost at sea as % of caught 2% 2% 4% 3% 3% 6% 8% 2% 3% 2% 8% 9% 3% 1% 8% 19% 8% 8% 16% 11% 6% 9% 7% 24% 22% 15% 19% 13% 15% 17% 20% 20% 19% 20% 23% 22% 25% 22% 28% 23% 25% 23% 21% 23% 25% 25% 26% 24% 23% 21% 22% 21% 24% 27% 22% 24% 23% 26% 25% 24% 28% 1960–1969 1970–99 Includes struck and lost. 2000–2012 Includes struck and lost. 2013–15 includes struck and lost. 2014 Arviat 1996–2002
2003–16 1954–99 1954–1985 cites Russian papers NMFS cites Russian paper This table uses their "high" estimate, since they say, page 23: "The high take scenario is considered the better of the two because it accounts for times when takes are known to have occurred but are not documented. Additionally, we did not account for beluga whales that are struck and lost because these data are not available, so the high take option may even be an underestimate." Western Okhotsk Sources Total of columns at left, incomplete 1954–2016 Paper is not online. This table uses their "high" estimate (which includes struck and lost), without harvests from ice entrapments (which would die even if not harvested). Total of columns at left, incomplete Total of other columns
Predation
Contamination
Pathogens
Relationship with humans
Captivity
Whale watching
Human speech
Conservation status
Legal protection
Conservation research in managed care facilities
Cultural references
See also
Further reading
External links
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