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121-524: The strait connects the Beaufort Sea in the west with Viscount Melville Sound in the east. It is bounded by Prince Patrick Island , Eglinton Island and Melville Island on the north and Banks Island on the south. As the strait is chronically blocked with thick ice , it is usually impassable to ships; in 1969, the United States -registered tanker SS Manhattan was freed from the ice by

242-589: 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

363-662: A moratorium on commercial fishing of the Beaufort Sea north of Alaska, including the disputed waters. In July 2010, US–Canada negotiations have started in Ottawa with the next meeting planned in 2011. A joint geological survey of the area has been initiated, and the issue was marked as settled by the CIA World Factbook , though no official document has been released by September 2010. On August 20, 2009 United States Secretary of Commerce Gary Locke announced

484-500: A moratorium on fishing the Beaufort Sea north of Alaska. According to Locke: "As Arctic sea ice recedes due to climate change, there is increasing interest in commercial fishing in Arctic waters. We are in a position to plan for sustainable fishing that does not damage the overall health of this fragile ecosystem. This plan takes a precautionary approach to any development of commercial fishing in an area where there has been none in

605-762: A Canadian icebreaker , and forced to travel through Canadian territorial waters to complete its westward passage. Ice prevented Manhattan from going through McClure Strait so the vessel sailed through the Prince of Wales Strait . There is a dispute between Canada and the United States over the waters of the Arctic Islands , other than those within 12 mi (19 km) of shore. The M'Clure Strait became fully open (ice-free) in early August 2007, and again in August 2008. The European Space Agency reported that

726-673: 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. Mitochondrial DNA studies have shown modern cetaceans last shared a common ancestor between 25 and 34 million years ago The superfamily Delphinoidea (which contains monodontids, dolphins and porpoises) split from other toothed whales, odontoceti, between 11 and 15 million years ago. Monodontids then split from dolphins (Delphinidae) and later from porpoises (Phocoenidae), their closest relatives in evolutionary terms. In 2017

847-431: A beluga's life expectancy was rarely more than 30 years. The method used to calculate the age of a beluga is based on counting the layers of dentine and dental cement in a specimen's teeth, which were originally thought to be deposited once or twice a year. The layers can be readily identified as one layer consists of opaque dense material and the other is transparent and less dense. It is therefore possible to estimate

968-421: 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. Belugas are slower swimmers than the other toothed whales, such as

1089-401: 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

1210-643: A chance, such as carcasses and whales trapped in ice fields. "There is only one proposed Early-Entry site in eastern Beringia that still has proponents, Bluefish Caves in the Porcupine River Basin, Yukon Territory, Canada. Claims of great antiquity in the area [e.g., 30kya] have a convoluted history. A caribou tibia flesher, the most diagnostic human implement from the Old Crow basin, had been dated at near 28 kya. When redated using accelerator mass spectrometry (AMS) of small amounts of remnant collagen

1331-570: A discontinuous circumpolar distribution in Arctic and sub-Arctic waters. During the summer, they can mainly be found in deep waters ranging from 76°N to 80°N , particularly along the coasts of Alaska , northern Canada, western Greenland and northern Russia. The southernmost extent of their range includes isolated populations in the St. Lawrence River in the Atlantic, and the Amur River delta,

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1452-436: 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 lungs , 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 Weddell seals (a diving marine mammal). One study found

1573-541: 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 bowhead whales , for curiosity and to secure polynya feasibility to breathe as bowheads are capable of breaking through ice from underwater by headbutting. Belugas play an important role in

1694-400: A few centimetres behind their eyes; each hole communicates with an external auditory conduit and an eardrum . It is not known if these organs are functional or simply vestigial . 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

1815-426: A few days be hundreds of miles away from that pod. Beluga whale pods can be grouped into three categories, nurseries (which consist of mother and calves), bachelors (which consist of all males) and mixed groups. Mixed groups contain animals of both sexes. Many hundreds and even thousands of individuals can be present when the pods join in river estuaries during the summer. This can represent a significant proportion of

1936-410: 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 cal per ounce . The calves remain dependent on their mothers for nursing for

2057-446: A food for seabirds and fish, primarily as polar cod and Arctic char. Polar cod is a major food of Arctic char, beluga, narwhal , seabirds and seals, which are dominated by the bearded seal ( Erignatus barbatus ) and ringed seal ( Pusa hispida ). Bearded seal and walrus also feed on benthic invertebrates. On top of the food pyramid stands the polar bear, which feeds primarily on seals, but also on any large marine mammals when it has

2178-450: A large frontal prominence. Another distinctive characteristic it possesses is the melon is malleable; its shape is changed during the emission of sounds. The beluga is able to change the shape of its head by blowing air around its sinuses to focus the emitted sounds. This organ contains fatty acids , mainly isovaleric acid (60.1%) and long-chain branched acids (16.9%), a very different composition from its body fat, and which could play

2299-402: A maritime boundary where there are no special circumstances in the area and when equidistance results in a boundary in accordance with equitable principles". Canada contends that an equidistance principle does not result in an equitable boundary, because distortion would occur. The coast of Yukon is concave, whereas the coast of Alaska is convex; and thus an equidistance principle would result in

2420-490: 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

2541-403: A mechanism for regulating body temperature , as the arteries feeding the fin's muscles are surrounded by veins that dilate or contract to gain or lose heat. The tailfin is flat with two oar-like lobes, it does not have any bones, and is made up of hard, dense, fibrous connective tissue. The tailfin has a distinctive curvature along the lower edge. The longitudinal muscles of the back provide

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2662-538: 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

2783-472: A position that the U.S. rejects. This dispute is in this respect a mirror image of the dispute between the U.S. and Canada over the Gulf of Maine , where the U.S. argued for "special circumstances" and Canada argued for the equidistance principle. (In that latter dispute, both of those arguments were rejected, and the border was drawn based upon geometric principles taking into account geographic factors. ) Neither

2904-466: A role in its echolocation system. Unlike many dolphins and whales, the seven vertebrae 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

3025-501: A significant extension of the U.S. possession. This dispute has taken on increased significance due to the possible presence of natural reserves within the wedge, which according to Canada's National Energy Board may contain 1,700,000,000 m (6.0 × 10  cu ft) of gas, which would cover the national consumption for 20 years, and more than 1,000,000,000 m (3.5 × 10  cu ft) of oil. Because of this, Canada argues that "special circumstances" apply to this border,

3146-559: A similar interpretation under the treaty whereby it acquired Alaska . Both the U.S. and Canada agree that they are bound by the 1958 Convention on the Continental Shelf ; and they both agree that the boundary should be "equitable", as determined by the International Court of Justice . They differ on what should be deemed "equitable". The U.S. contends that "equidistance is an appropriate principle for determining

3267-493: 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 estuaries and shallow coastal areas. They are slow swimmers, but can dive to 700 m (2,300 ft) below

3388-965: A temperature of −1.4 °C (29.5 °F) in summer and −1.8 °C (28.8 °F) in winter. The next layer is formed by the inflows from the Pacific Ocean and Bering Sea coming through the Bering Strait ; it extends up to the North Pole . The warmest, deep Atlantic layer has the temperatures between 0 and 1 °C (32 and 34 °F), and water at the bottom is a bit colder at −0.4 to −0.8 °C (31.3 to 30.6 °F). The average salinity varies between 28‰ and 32‰ (parts per thousand) from south to north. Typical air temperatures (at Tuktoyaktuk) are −27 °C (−17 °F) in January and 11 °C (52 °F) in July. The water currents form

3509-506: 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

3630-405: A way of preserving heat. The crest is hard and, along with the head, can be used to open holes in ice up to 8 cm (3.1 in) thick. The beluga has a very specialised sense of hearing and its auditory cortex is highly developed. It can hear sounds within the range of 1.2 to 120  kHz , with the greatest sensitivity between 10 and 75 kHz, where the average hearing range for humans

3751-420: 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 teeth 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

M'Clure Strait - Misplaced Pages Continue

3872-508: Is Coho salmon ( Oncorhynchus kisutch ). In general, the diets of these cetaceans consist mainly of fish; apart from those previously mentioned, other fish they feed on include capelin ( Mallotus villosus ), smelt , sole , flounder , herring , sculpin and other types of salmon . They also consume a great quantity of invertebrates, such as shrimp , squid , crabs , clams , octopus , sea snails , bristle worms and other deep-sea species. Belugas feed mainly in winter as their blubber

3993-429: 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 beluga inhabits

4114-404: Is 0.02 to 20 kHz. The majority of sounds are most probably received by the lower jaw and transmitted towards the middle ear . In the toothed whales, the lower jawbone is broad with a cavity at its base, which projects towards the place where it joins the cranium . A fatty deposit inside this small cavity connects to the middle ear. Toothed whales also possess a small external auditory hole

4235-778: Is a marginal sea of the Arctic Ocean , located north of the Northwest Territories , Yukon , and Alaska , and west of the Canadian Arctic Archipelago . The sea is named after Sir Francis Beaufort , a hydrographer . The Mackenzie River , the longest in Canada , empties into the Canadian part of the Beaufort Sea west of Tuktoyaktuk , which is one of the few permanent settlements on the sea's shores. The sea, characterized by severe climate,

4356-511: Is a slight difference on the sexual maturation period between males and females. The male beluga whales take seven to nine years to become sexually mature, while the females take four to seven years. 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

4477-446: 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

4598-404: 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

4719-611: 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 ( polar bears and killer whales ), contamination of rivers (as with polychlorinated biphenyl (PCBs) which bioaccumulate up the food chain), climate change and infectious diseases . The beluga

4840-464: Is frozen over most of the year. Historically, only a narrow pass up to 100 km (62 mi) opened in August–September near its shores, but recently due to climate change in the Arctic the ice-free area in late summer has greatly enlarged. Until recently, the Beaufort Sea was known as an important reservoir for the replenishment of Arctic sea ice. Sea ice would often rotate for several years in

4961-512: 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 1.5 m (4 ft 11 in) long, weigh about 80 kg (180 lb), 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

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5082-509: Is in turn part of the parvorder Odontoceti (toothed whales). The Irrawaddy dolphin was once placed in the same family, though recent genetic evidence suggests these dolphins belong to the family Delphinidae . The narwhal is the only other species within the Monodontidae. A skull has been discovered with intermediate characteristics supporting the hypothesis that hybridisation is possible between these two species. The name of

5203-399: Is rarely mistaken for any other species, because it is completely white or whitish-grey in colour. Calves are usually born grey, and by the time they are a month old, have turned dark grey or blue grey. They then start to progressively lose their pigmentation until they attain their distinctive white colouration, at the age of seven years in females and nine in males. The white colouration of

5324-587: Is relatively small owing to the cold climate. Major fish species include polar cod ( Boreogadus saida ), Arctic cod ( Arctogadus glacialis ), saffron cod ( Eleginus gracilis ), Arctic char ( Salvelinus alpinus ), chum salmon ( Oncorhynchus keta ), Arctic cisco ( Coregonus autumnalis ), least cisco ( Coregonus sardinella ), lake whitefish ( Coregonus clupeaformis ), broad whitefish ( Coregonus nasus ), Pacific herring ( Clupea pallasii ), fourhorn sculpin ( Myoxocephalus quadricornis ), inconnu ( Stenodus leucichthys ) and flatfish . The eastern part of

5445-608: 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 15 cm (5.9 in) 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. The adult beluga

5566-432: Is that of a still extant animal). Its body is round, particularly when well fed, and tapers less smoothly to the head than the tail. The sudden tapering to the base of its neck gives it the appearance of shoulders, unique among cetaceans. The tail-fin grows and becomes increasingly and ornately curved as the animal ages. The flippers are broad and short—making them almost square-shaped. Preliminary investigations suggested

5687-623: 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 18.2 to 27.2 kg (40 to 60 lb). Like their wild counterparts, captive belugas were found to eat less in the fall. Foraging on the seabed typically takes place at depths between 20 and 40 m (66 and 131 ft), although they can dive to depths of 700 m (2,300 ft) in search of food. Their flexible necks provide

5808-507: Is thickest in later winter and early spring, and thinnest in the fall. Inuit observation has led scientists to believe that belugas do not hunt during migration, at least in Hudson Bay. 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 Pacific sand lance . Shrimp are

5929-456: Is unclear as to whether belugas receive a different number of layers per year depending on the age of the animal (for example young belugas may only receive an additional one layer per year), or simply just one layer per year or every other year. The species presents a moderate degree of sexual dimorphism , as the males are 25% longer than the females and are sturdier. Adult male belugas can range from 3.5 to 5.5 m (11 to 18 ft), while

6050-459: The 141st meridian west out to a distance of 200  nmi (370 km; 230 mi), following the Alaska–Yukon land border. This follows the natural prolongation principle , which holds that a nation's maritime boundary should reflect the 'natural prolongation' of where its land territory reaches the coast. The position of the United States is that the boundary line should be perpendicular to

6171-571: The Arctic 's Northwest Passage opened up fully sea ice free, clearing a lane through the northern section of the historically impassable route between Europe and Asia. At 15.33Z on August 29, 2012, the purpose-built Polar Bound under the command of David Scott Cowper with Jane Maufe as crew, was the first private yacht to pass through the strait. Shortly thereafter, the Hallberg-Rassy sailboat Belzebub II , with three sailors aboard, became

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6292-631: The Athabaskan First Nations peoples and Inuit during 1920–1960, but has since declined. The Beaufort Sea contains major gas and petroleum reserves beneath the seabed, a continuation of proven reserves in the nearby Mackenzie River and North Slope. The Beaufort Sea was first explored for sub-shelf hydrocarbons in the 1950s and estimated to contain about 250 km (60 cu mi) of oil and 300,000 km (72,000 cu mi) of natural gas under its coastal shelf. Offshore drilling began in 1972; about 70 wells were set up by

6413-522: The Beaufort Gyre , the dominant ocean current of the Beaufort Sea, growing into sturdy and thick multi-year ice. Claims that the seacoast was populated about 30,000 years ago have been largely discredited (see below); present population density is very low. The sea contains significant resources of petroleum and natural gas under its shelf, such as the Amauligak field. They were discovered in

6534-751: The Kongakut River in Alaska and the Firth River in Yukon empty into the Beaufort. The major river to flow into the sea is the Mackenzie, Canada's longest, which empties into the Canadian part of the sea, west of Tuktoyaktuk. The coastal shelf area is rather narrow, especially near and east of Point Barrow in the Alaskan part of the sea, and contains numerous submarine valleys . It becomes wider near

6655-654: The Treaty of Saint Petersburg (1825) between the United Kingdom and the Russian Empire that set the boundary between the two. Canada is the successor state to Great Britain in relation to this treaty, which stipulates: the line of demarcation shall follow the summit of the mountains situated parallel to the Coast, as far as the point of intersection of the 141st degree of West longitude […] and, finally, from

6776-584: The genus , Delphinapterus , means "dolphin without fin" (from the Greek δελφίν ( delphin ), dolphin and απτερος ( apteros ), without fin) and the species name leucas means "white" (from the Greek λευκας ( leukas ), white). The Red List of Threatened Species gives both beluga and white whale as common names, though the former is now more popular. The English name comes from the Russian белу́га, which derives from

6897-414: The 1980s and 200 wells by 2000. These activities resulted in dredging of about 46.5 million m3 of sea bottom soil, as well as discharge of drilling muds which contained barite , clay, caustic soda , and heavy metals zinc, copper, lead, chromium, cobalt, nickel, cadmium and mercury. About 50,400 m (1,780,000 cu ft) of oil was produced in 1986. A major gas field, named Taglu Gas Field ,

7018-648: The 1990s. The major settlements along the Beaufort Sea are Tuktoyaktuk (population 930 in 2009 ) in Canada and Prudhoe Bay, Alaska . Although Prudhoe Bay is permanently populated by only a few people, there are thousands of contract workers in the area employed on petroleum production at the Prudhoe Bay Oil Field , which is on the coastal lowland known as the North Slope . Artificial islands , such as Endicott and Northstar , have been raised near

7139-400: The 4,000 years old settlements. While originally they lived nomadic life, later, they started to form permanent settlements. Their population is increasing, but the unemployment rate is relatively high. Bowhead whales were hunted in the sea between 1888 and 1914. This practice stopped, first because of the decline in whale population and then because of government regulations, but resumed in

7260-578: The Arctic , the ice-free area in late summer greatly enlarged. During the record minimum extent of Arctic sea ice in September, 2012, the sea ice boundary had retreated northward much farther than normal from the coast. The channels of the Mackenzie River thaw earlier, in late May–early June. This thawing increases the average water discharge from about 150,000 to 250,000 m /s (5,300,000 to 8,800,000 cu ft/s). Hidden changes in

7381-406: The Beaufort Sea are clearly distinct from those of other Canadian and Alaskan waters, despite often sharing a common wintering habitat. The food chain of the Beaufort Sea is relatively simple: It starts with phytoplankton and epontic algae (single-cell algae associated with the lower interface of sea ice ), which provide energy to zooplankton, and epontic and coastal amphipods. The latter serve as

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7502-680: The Beaufort Sea as Marine Protected Areas (MPAs). The Anguniaqvia niqiqyuam MPA surrounds the Parry Peninsula in the Amundsen Gulf , and the Tarium Niryutait MPA is located at the Mackenzie River delta and estuary. The protected areas are set to protect species and habitats for the Inuvialuit community. The International Hydrographic Organization defines the limits of the Beaufort Sea as follows: On

7623-620: The Beaufort Sea is covered with tundra and marks the northern limit of the terrestrial range of the polar bear in North America. The Mackenzie River is an important habitat for whales and seabirds and is still relatively untouched by commercial traffic. The delta of Mackenzie River contains numerous lakes and ponds which are inhabited by muskrat . The sea hosts about 80 species of zooplankton , more than 70 species of phytoplankton , and nearly 700 species of polychaetes , bryozoans , crustaceans and mollusks , but their total volume

7744-407: The Beaufort Sea. Stan Rogers references the Beaufort Sea in his popular Canadian Folk Song " Northwest Passage ". Beluga whale The beluga whale ( / b ɪ ˈ l uː ɡ ə / ; Delphinapterus leucas ) is an Arctic and sub-Arctic cetacean . It is one of two members of the family Monodontidae , along with the narwhal , and the only member of the genus Delphinapterus . It

7865-463: The Mackenzie River, such as Herschel Island (4 km (2.5 mi) off the shore, area 18 km (6.9 sq mi)) and Barter Island (0.3 km (0.19 mi) from the coast, area 13 km (5.0 sq mi)). The coasts are low, with the maximum elevations between 250 and 750 m (820 and 2,460 ft). The soil is frozen all year around at the depth below about 1 m (3 ft 3 in) or less, forming permafrost , and only

7986-637: The North. A line from Point Barrow , Alaska, to Lands End, Prince Patrick Island ( 76°16′N 124°08′W  /  76.267°N 124.133°W  / 76.267; -124.133 ). On the East. From Lands End through the Southwest coast of Prince Patrick Island to Griffiths Point, thence a line to Cape Prince Alfred, the Northwestern extreme of Banks Island , through its West coast to Cape Kellet,

8107-556: The Southwestern point, and thence a line to Cape Bathurst on the mainland ( 70°36′N 127°32′W  /  70.600°N 127.533°W  / 70.600; -127.533 ). There is an unresolved dispute involving a wedge-shaped slice on the International Boundary in the Beaufort Sea, between the Canadian territory of Yukon and the U.S. state of Alaska. Canada claims the maritime boundary to be along

8228-604: The U.S. nor Canada has pressed for a swift resolution for the matter, or arbitration at the International Court of Justice, however; and the two have in the meantime cooperated in several measures aimed at preserving the maritime environment. Before the end of 2004, the US leased eight plots of land below the water for oil exploration and exploitation, provoking a diplomatic protest from Canada. On 20 August 2009, United States Secretary of Commerce Gary Locke announced

8349-564: The US adopted a precautionary commercial fisheries management plan in August 2009. In April 2011, the Canadian government signed a memorandum of understanding with the Inuvialuit as a first step in developing a larger ocean management plan. The Canadian government announced in October 2014 that no new commercial fisheries in the Beaufort Sea will be considered until research has shown sustainable stocks that would be made available to Inuvialuit first. The Canadian government designated blocks of

8470-434: 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 5.5 m (18 ft) long and weighing up to 1,600 kg (3,530 lb). This whale has

8591-423: The age of the individual by extrapolating the number of layers identified and the estimated frequency with which the deposits are laid down. A 2006 study using radiocarbon dating of the dentin layers showed the deposit of this material occurs with a lesser frequency (once per year) than was previously thought. The study therefore estimated belugas can live for 70 or 80 years. However, recent studies suggest that it

8712-440: 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

8833-439: The ascending and descending movement of the tailfin, which has a similar thermoregulation mechanism to the pectoral fins. 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 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

8954-501: The beam of sound. They use this ability when moving around thick Arctic ice sheets, to find areas of unfrozen water for breathing, or air pockets trapped under the ice. 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

9075-416: The beluga's mammalian ancestors, and are firmly bound together by connective tissue . The fins are small in relation to the size of the body, rounded and oar-shaped and slightly curled at the tips. These versatile extremities are mainly used as a rudder to control direction, to work in synchrony with the tailfin and for agile movement in shallow waters up to 3 m (9.8 ft) deep. The fins also contain

9196-550: The beluga's range varied with that of the polar ice packs expanding during ice ages 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, 240 km (150 mi) from the Atlantic Ocean. The bones were discovered during construction of the first railroad between Rutland and Burlington in Vermont, when workers unearthed

9317-440: 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

9438-510: The bone produced a 1.8 kya date (Yesner 1996b:255)". There is no evidence for anomalous occupation of Beaufort coasts in the context of Arctic cultures generally, including the arrival about 4,000 years ago by Paleo-Eskimos such as the Dorset culture , around 1,000 years ago by the Thule and finally by the modern Inuit . From early ages, they practiced fishing – bones of Arctic char were found at

9559-406: The bones of a mysterious animal in Charlotte . Buried nearly 10 ft (3.0 m) 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 150 mi (240 km) from the nearest ocean, early naturalists were at a loss to explain the presence of the bones of

9680-418: The clockwise-directed Beaufort Gyre , that results in south-westerly and westerly currents near the shores. The Mackenzie River partly affects this circulation inducing minor eastwards streams near its mouth. The river annually brings about 15 million tonnes of sediments which are rich in dolomite and calcium carbonate . Those deposits are spread over the sea and mixed with mud and gravel. The shoreline of

9801-454: The coast out to a distance of 200 nmi (370 km; 230 mi), following a line of equidistance from the coast. The equidistance principle argues that a nation's maritime boundaries should conform to a median line that is equidistant from the shores of neighbouring nations. This difference creates a wedge with an area of about 21,000 km (8,100 sq mi) that is claimed by both nations. Canada's position has its roots in

9922-410: The delta of the Mackenzie River but nowhere exceeds 145 km (90 mi). Near the coast, the depths are shallower than 60 m (200 ft) but they rapidly increase northwards up to a few kilometers, transforming into a massive platform which is geologically similar to that of the oceans. There are many small islands in the sea and in the delta of the Mackenzie River. A few larger ones lie west of

10043-633: The disputed area covered a 21,436 square kilometres (8,276 sq mi) section of the Beaufort Sea. He wrote that Canada had filed a " diplomatic note " with the US in April when the USA first announced plans for the moratorium. Jack Layton , leader of the New Democratic Party of Canada , called the U.S. moratorium over the disputed waters in the Beaufort Sea the "largest encroachment on Canadian territory in our history." Several rivers such as

10164-477: 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,

10285-465: 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 chemoreceptors 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

10406-429: The females measure 3 to 4.1 m (9.8 to 13.5 ft). Males weigh between 1,100 and 1,600 kg (2,430 and 3,530 lb), and occasionally up to 1,900 kg (4,190 lb) while females weigh between 700 and 1,200 kg (1,540 and 2,650 lb). They rank as mid-sized species among toothed whales. Individuals of both sexes reach their maximum size by the time they are 10 years old. The beluga's body shape

10527-616: The first sailboat to travel the route. The M'Clure Strait lies within the M'Clure Rift which forms the western end of the Parry Submarine Rift Valley. It is considered an incipient rift zone because little extensional tectonism has taken place on it and no oceanic crust occurs in the middle of the strait. 74°42′N 117°00′W  /  74.7°N 117.0°W  / 74.7; -117.0 Beaufort Sea The Beaufort Sea ( / ˈ b oʊ f ər t / BOH -fərt ; French : Mer de Beaufort )

10648-494: 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

10769-510: The fish. Estimations of the age of sexual maturity for beluga whales vary considerably; the majority of authors estimate males reach sexual maturity when they are between nine and fifteen years old, and females reach maturity between eight and fourteen years old. The average age at which females first give birth is 8.5 years and fertility begins to decrease when they are 25, eventually undergoing menopause, and ceasing reproductive potential with no births recorded for females older than 41. There

10890-451: The genome of a beluga whale was sequenced, comprising 2.327 Gbp of assembled genomic sequence that encoded 29,581 predicted genes. The authors estimated that the genome-wide sequence similarity between beluga whales and killer whales is 97.87%. 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

11011-467: The ice cover of the Beaufort Sea were discovered in 2009. Whereas the ice area remain stable, as detected by the observation satellites, so as the associated water temperature and salinity , the ice structure has changed recently. The new ice, called rotten ice , is thinner and much weaker structurally. The sea water has a stable temperature and is separated into four distinct layers as follows. The top 100 m (330 ft) are surface water which has

11132-412: 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

11253-410: The killer whale and the common bottlenose dolphin , because they are less hydrodynamic and have limited movement of their tail-fins, which produce the greatest thrust. They frequently swim at speeds between 3 and 9 km/h (1.9 and 5.6 mph), although they are able to maintain a speed of 22 km/h for up to 15 min. Unlike most cetaceans, they are capable of swimming backwards. Belugas swim on

11374-544: The most common invertebrate eaten, with octopus, amphipods and echiurids 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

11495-413: The most commonly kept cetaceans in captivity and are housed in aquariums, dolphinariums 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 beluga was first described in 1776 by Peter Simon Pallas . It is a member of the family Monodontidae , which

11616-416: The muscular covering to open the spiracle. A beluga's thyroid gland is larger than that of terrestrial mammals —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 hyperplastic and neoplastic lesions of the thyroid. The fins retain the bony vestiges of

11737-425: 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

11858-450: The other toothed whales, their brains lack olfactory bulbs and olfactory nerves, which suggests they do not have a sense of smell. These cetaceans are highly sociable and they regularly form small groups, or pods, that may contain between two and 25 individuals, with an average of 10 members. Pods tend to be unstable, meaning individuals tend to move from pod to pod. Radio tracking has even shown belugas can start out in one pod and within

11979-409: The past." There is no widespread commercial fisheries in those waters now. The moratorium was imposed in anticipation that global warming would make those waters accessible to commercial fisheries. The moratorium stirred controversy in Canada because the region where the USA announced the moratorium included a large wedge-shaped region of disputed waters. Randy Boswell, of Canada.com wrote that

12100-440: The period between the 1950s and 1980s, and since the latter part of that period their exploration has become the major human activity in the area. The traditional occupations of fishing and whale and seal hunting are practiced only locally, and have no commercial significance. As a result, the sea hosts one of the largest colonies of beluga whales , and there is no sign of overfishing as of now. To prevent overfishing in its waters,

12221-501: The said point of intersection, the said Meridian Line of the 141st degree, in its prolongation as far as the Frozen Ocean Canada maintains that this treaty is extensible from the land into the Beaufort Sea along the meridian. The United States rejects this extension and instead asserts a boundary line based upon equidistance, although its position is somewhat undermined by its acceptance in 1867 of similar treaty wording and

12342-422: The sea is a major habitat of beluga whales with an estimated population of 39,000. This population is stable and might even be increasing; it is not affected by the offshore oil exploration in the area. Belugas spend summer in the coastal area and Mackenzie River delta, which are free of ice then, and in winter migrate long distances to the polynyas of the deep sea. Genetic analyses have confirmed that belugas of

12463-551: The sea". Like the other toothed whales, belugas do not possess vocal cords 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

12584-503: The shores in 1987 and 2001, respectively. The crude oil is transported through the Trans-Alaska Pipeline System to the southern port of Valdez . Fishing and sea hunting are practised by the local inhabitants and have no commercial value, especially after a US moratorium on commercial fishing of the Beaufort Sea, adopted in 2009. Trapping of muskrat at the Mackenzie River delta was the main source of income for

12705-418: 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. Belugas use sounds and echolocation for movement, communication, to find breathing holes in the ice, and to hunt in dark or turbid waters. They produce a rapid sequence of clicks that pass through the melon, which acts as an acoustic lens to focus

12826-411: The skin is an adaptation to life in the Arctic that allows belugas to camouflage themselves in the polar ice caps as protection against their main predators, polar bears and killer whales . Unlike other cetaceans, the belugas seasonally shed their skin. During the winter, the epidermis thickens and the skin can become yellowish, mainly on the back and fins. When they migrate to the estuaries during

12947-430: The sounds into a beam that is projected forward through the surrounding water. These sounds spread through the water at a speed of nearly 1.6 km per second, some four times faster than the speed of sound in air. The sound waves reflect from objects and return as echoes that are heard and interpreted by the animal. This enables them to determine the distance, speed, size, shape and the object's internal structure within

13068-565: The structure and function of marine resources in the Arctic Ocean , as they are the most abundant toothed whales in the region. They are opportunistic feeders; their feeding habits depend on their locations and the season. For example, when they are in the Beaufort Sea , they mainly eat Arctic cod ( Boreogadus saida ) and the stomachs of belugas caught near Greenland were found to contain rose fish ( Sebastes marinus ), Greenland halibut ( Reinhardtius hippoglossoides ) and northern shrimp ( Pandalus borealis ), while in Alaska their staple diet

13189-410: The summer, they rub themselves on the gravel of the riverbeds to remove the cutaneous covering. Like most toothed whales , the beluga has a compartment found at the centre of the forehead that contains an organ used for echolocation called a melon , which contains fatty tissue. The shape of the beluga's head is unlike that of any other cetacean, as the melon is extremely bulbous, lobed and visible as

13310-449: The surface between 5% and 10% of the time, while for the rest of the time they swim at a depth sufficient enough to cover their bodies. They do not jump out of the water like dolphins or killer whales. These animals usually only dive to depths to 20 m (66 ft), 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

13431-560: 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 migratory 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

13552-408: The top few tens of centimeters thaws in summer. Consequently, buildings have to be elevated above ground on wooden piles that are immersed into the permafrost. The Beaufort Sea is frozen over through the year, except for August and September when the ice breaks near the coast and opens what was once a 50–100 km (31–62 mi) wide strip of open water. During the 2000s, due to climate change in

13673-545: The total population and is when they are most vulnerable to being hunted. 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

13794-600: 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

13915-477: 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

14036-646: The word белый ( bélyj ), meaning "white". Nowadays the word белу́га in Russian refers to the beluga sturgeon , while the whale is called almost similarly - белу́ха ("belúha"). 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

14157-513: 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

14278-555: Was discovered in 1984, and is estimated to contain 37.3 km (8.9 cu mi) of oil and 38,500 km (9,200 cu mi) of gas. The development of these fields is hindered by their remote location. This problem was alleviated for Prudhoe Bay by constructing the Trans-Alaska Pipeline, but is limiting regular commercial production at Mackenzie River deposits. For example, the Amauligak Project

14399-473: Was discovered in the Mackenzie River delta in 1971, followed by the Parson Lake field and Niglintgak field. The estimated gas reserves of these fields are 58,600 km (14,100 cu mi), 35,400 and 13,600 km (8,500 and 3,300 cu mi), respectively. Moreover, further into the sea from the Mackenzie delta lies the Amauligak field. This, the largest known oil deposit of the Beaufort Sea,

14520-631: 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

14641-506: Was started soon after the discovery of the field. In September 1985, the tanker Gulf Beaufort has transported 50,300,000 L (316,377 bbl) of crude oil to Japan, which was the first shipment of oil from the Arctic deposits. However, the project has stalled after that. In July 2017, the U.S. Bureau of Ocean Energy Management approved a plan to allow Eni , an Italian multinational oil and gas company, to drill four oil exploration wells on Spy Island, one of four artificial islands in

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