All About Belugas

All About Belugas

Belugas are the most adorable of God’s creatures that I know of; unfortunately, they are considered “near threatened” by the International Union for Conservation of Nature. The subpopulation living in Cook Inlet in Alaska is considered critically endangered, and fortunately is now under the protection of the United States’ Endangered Species Act.  Of seven Canadian Beluga populations two are listed as endangered: those inhabiting eastern Hudson Bay and Ungava Bay. Since knowledge is the best weapon I shall attempt to better acquaint you with Belugas.

First some interesting facts:

The Beluga or white whale, Delphinapterus Leucas, is an Arctic and sub-Arctic cetacean. It is one of two members of the family Monodontidae, along with the narwhal.  This fantastic marine mammal is commonly referred to as the Beluga (meaning ‘white’ in Russian) or, sometimes, sea canary due to its high pitched twitter.

Male Belugas are larger than females. Male Belugas’ length can range from 2.6 to 6.7m (8.5 to 22 ft), averaging 4 m (13ft), female averages 3.6m (12ft) in length. The males weigh between 700 and 1,200kg (1,500 and 2,600lb).  They rank as a  mid-sized species among toothed whales.

A Beluga is completely white or whitish gray (calves are usually gray) with a distinctive protuberance on the head.    This melon, an oily, fatty lump of tissue found at the center of the forehead, is extremely bulbous and even malleable.  The Beluga is able to change the shape of the melon by blowing air around its sinuses.  The vertebrae in the Beluga neck are not fused together (as in dolphins and other whales) allowing Belugas to turn its head.  Belugas have about 8 to 10 teeth on each side of the jaw and on an average of 34 to 40 teeth in total.

The Beluga’s body is round in cross-section, especially when he or she is well-fed, and tapers less smoothly to the head than the tail.

A sudden tapering to the base of its neck gives it the appearance of shoulders, a feature unique among cetaceans.

Beluga’s have a dorsal ridge instead of dorsal fin.  This evolutionary preference for a dorsal ridge rather than fin is likely an adaptation to under-ice conditions, and possibly allows a way of preserving heat.  The thyroid gland is also relatively large compared to terrestrial mammals and therefore may actually help them to sustain higher metabolism during the summer when they migrate to the river waters.

The tail fins of Belugas grow, becoming increasingly curved and ornately shaped as this mammal ages. The flippers are broad and short, almost square-shaped.

Male Belugas reach sexual maturity between four and seven years, while female Belugas mature at between six and nine years. The lifespan of Beluga can be more than fifty years.

The Beluga is considered a slow swimmer that feeds mainly on fish. It also feeds on cephalopods, such as squid and octopi, and crustaceans, such as crab and shrimp. Foraging for food on the seabed usually takes place at the depths of up to 300 m (1,000 ft); however the depth they can dive is twice this.  On average the feeding dive lasts three to five minutes, but Belugas can submerge for up to twenty minutes at a time.

Belugas are particularly vulnerable when they become trapped by ice and are unable to reach the ocean.  At such times polar bears; their primary natural enemy besides humans, swipe at the Belugas and drag them onto the ice. The orca is considered to be a major ocean predator.

Range and habitat

The Beluga lives in Arctic and sub-Arctic waters ranging from the Gulf of Saint Lawrence to Alaska, Greenland and Siberia.

Because its summer habitat usually clogs with ice during autumn months, the Belugas move away for the winter. They travel in the direction of the advancing icepack and stay close to its edge for the winter months. Some stay under the icepack, surviving by finding ice leads and patches of open water in the ice into which they can surface to breath. Sometimes they find air pockets trapped under the ice.  A Beluga’s echo-location capabilities are highly adapted to the sub-ice sea’s particular acoustics and it is most likely that Belugas can sense open water through their natural sonar.

In the spring, the Beluga moves to its summer grounds: bays, estuaries and other shallow inlets.  These summer sites are split apart from each other. Mothers usually return to the same site year after year.

Reproduction:

Belugas are considered to be highly sociable.  Mothers and calves form the Beluga’s closest social relationship.  Female Belugas typically give birth to one calf every three years.  Most mating occurs between February and May; however some mating occurs at other times of year.  Gestation lasts 12 to 14.5 months.   Newborns are about 1.5 metres (4.9ft) long, weigh about 80 kilograms (180 lb), and are grey in colour. .  Nursing times as long as two years have been noted while the calves remain dependent on their mothers for the whole period. Calves are born over a protracted period that varies by location;   in the Canadian Arctic, calves are born between the months of March and September; while in Hudson Bay, it is late June and in Cumberland sound births occur from late July to early August. Calves often return to the same estuary as their mother in the summer, meeting her sometimes even after becoming fully mature.  In pods groups of males may number in the hundreds, while mothers with calves generally mix in slightly smaller groups.  The collective pods in estuaries may number at times in the thousands. This can represent a significant proportion of the entire population and unfortunately, being rendered most vulnerable, this is when they are at the most risk of being hunted.

Another disadvantage is that pods tend to be unstable, the Belugas move from pod to pod. Individual Belugas may start out in one pod and, within a few days, be hundreds of miles away.

Belugas, unlike most whales, are capable of swimming backwards. Belugas are usually playful and they may spit at humans or other whales.  Some researchers believe that spitting originated with blowing sand away from crustaceans at the sea bottom.

Belugas and Humans

Unfortunately over the years both the Russian United States Navys have used Belugas in anti-mining operations in the Arctic waters.  They are favoured because of their intelligence and sensitivity. It is no surprise to learn of an instance, presumably during training, when a captive Beluga brought an incapacitated diver from the bottom of the pool up to the surface by holding her foot in its mouth, thus saving her life.

Because of their fantastic disposition, their attractive colour and the range of their facial expressions Belugas have always been an irresistible draw to humans. While most cetacean “smiles” are fixed, the extra movement afforded by the Beluga’s simple cervical vertebrae, allows them a great range of expressions. As a result they are highly sought after and were among the first whale species to be exhibited in captivity, as far back as 1861 when they were exhibited at Barnum’s Museum in New York City.  To date, they remain one of the few whale species that are kept in aquaria and sea life parks across North America, Europe and Asia.

The Beluga, because of its predicable migration pattern and high concentrations, has been hunted by the indigenous Arctic peoples for centuries.  In many areas, hunting continues, and is believed to be sustainable. However, in areas such as Cook Inlet, Ungava Bay and off western Greenland, commercial operations have left the population in dire peril.  This, combined with indigenous whaling has placed the populations of Beluga’s in serious decline.

Today the Belugas are considered an endangered and protected species. The global population of Belugas to date stands at about 100,000.  Though this number can be considered greater than of many other cetaceans, it is actually much smaller than pre-hunting populations.  Because they are long lived and on top of the food chain, as well as bearing large amounts of fat and blubber, they are considered an excellent indicator of environment health and changes.  Because the Beluga congregates in river estuaries, pollution has been taking its toll on them.  Papillomaviruses have been found in the gastic compartments of Belugas in the St Lawrence River. Herpes virus as well has been detected on occasion in Belugas. Encephaltis and Protozoa Sarcocystis has have also been known to infect Belugas. Ciliates have been noted to colonize the blowhole, even though it may not be pathogenic. Meanwhile incidents of cancer have been reported to be on the rise due to St. Lawrence River pollution.  Beluga carcasses contain so many contaminants that they are treated as toxic waste with levels ranging between 240 ppm and 800 ppm of PCB’s found on their carcass. The long term effects of this pollution on the affected population, we are told, are not fully known.

Another form of danger, namely, Erysipelothrix rhusiopathiae bacilli, a likely source being the contaminated fish in their diet, can presently endanger captive Belugas, causing them anorexia, dermal plaques, and lesions.  This if not diagnosed early and treated with antibiotics, may lead to death.  The high numbers of captives adds to the threat to these magnificent mammals.  Take heart, at least something, however small, is being done about this. Researchers from the Vancouver Aquarium Marine Science Centre are finding ways to prevent fungi from entering the habitats and are constantly monitoring Belugas to maintain their good health.

All is not lost however. At long last mankind has shown the capacity for mercy.

As of 2008, the Beluga was listed as “near threatened” by the IUCN, due to uncertainty about number of Belugas over parts of its range (particularly the Russian Arctic).   The Cook Inlet subpopulation is listed as “Critically Endangered” by the IUCN as of 2006 then under the Endangered Species Act as of October 2008.  The Beluga whale is also listed on CMS (Migratory Species of Wild Animals) and will benefit significantly from international co-operation organized by tailored agreements.  A promising deterrence, Belugas are presently protected under the International Moratorium on Commercial Whaling even though unfortunately, a small amounts of Beluga whaling are still allowed.  Meanwhile, because their habitats include inland waters, it is easy for them to come I contact with oil and gas development with their related poisons. On an encouraging note, the Alaskan and Canadian governments are relocating these oil and gas sites so as to protect whales from coming in contact with resultant industrial waste.

The Beluga’s earliest known ancestor was the prehistoric Denebola brachyephala from the Miocene period.  A single fossil from the Baja California peninsula showed that the family once inhabited warmer waters and the Beluga’s range, in contrast to recent times, varied with that of the polar ice-packs; expanding during ice ages and contracting when the ice retreated.

Finally, we owe it to ourselves to do all we can to preserve this magnificent mammal.

 

 

 

 

 

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