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.
The End.
