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There are eight species of whales that frequent the cold and
icy waters of Alaska. The Beluga,
Humpback,
Gray, Orca,
Bowhead, Blue,
Right, and
Minke whales.
The distinctive whale known as the beluga whale is one of
several beaked whales that inhabit the Aortic. North Atlantic,
and North Pacific Oceans Russian explorers named the beluga
whale when they spotted them in the Bering Sea. Beluga means
"the white one". At birth, beluga whales are dark blue-gray in
color, measure 3-5 feet long, and weigh 90-130 lbs. The color
gradually lightens, usually turning white by age 5 or 6. Adult
beluga whales average 13-15 feet in length and weigh between
2,500 and 3,500 pounds.
Males reach sexual maturity between four and seven years, while females mature at between six and nine years. The beluga can live more than 50 years.
Belugas are robust-bodied and have a blubber layer which can be
as much as 5 inches thick. They are muscular creatures with a
small rounded head, a short beak, and are quite mobile in
comparison to other whales. The belugas have a narrow ridge that
runs down the rear of their backs, which allows them to swim
freely under floating ice. Also, the beluga is the only whale
that can bend its neck. This helps them to maneuver easily and
catch prey, using their 34 to 40 teeth, not for chewing, but for
grabbing and tearing their prey, which is then swallowed whole.
Belugas use sound to find their prey. They also use sound to
communicate and navigate by producing a variety of clicks,
chirps and whistles.
Two populations of beluga whales occur in Alaska. The Cook Inlet
population occurs in the inlet and Shelikof Strait region,
although wanderers have been seen east to Yakutat Bay and to
Kodiak Island. Belugas of the Bering Sea population range
throughout the Bering, Chukchi, and Beaufort seas.
In the summer beluga whales migrate in pods into Turnagain arm
and may be observed along the shore. Areas where beluga whales
concentrate, such as shallow tidal flats, larger river mouths,
estuarine areas, and certain areas where the level of human
related disturbance is low, provide a necessary combination
of physical and biological features that facilitate feeding,
breeding, and nursing. Additionally, ice in these regions in
the colder months may provide important barriers to
beluga predators.
Belugas prey on a wide variety of
animals, including octopus, squid, crabs, shrimp,
clams, mussels, snails, sandworms, polychaetes, and various fish such as cod,
herring, smelt, flounder, sole, sculpin, pollock,
lamprey, lingcod and salmon. In the spring, Cook
Inlet belugas primarily eat eulachon (a.k.a. hooligan
or candlefish), and switch primarily to salmon in the
summer. In the fall and winter, when eulachon and
salmon numbers are low, belugas diversify their diet
and spend more time feeding in deeper waters.
In 1849, while constructing the first railroad between Rutland
and Burlington in Vermont, workers unearthed the bones of a
mysterious animal in the town of Charlotte. Buried nearly 10
feet (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 miles (240 km) from the nearest
ocean, early naturalists were at a loss to explain the bones of
a marine mammal buried beneath the fields of rural Vermont.
On June 9, 2006, a young beluga carcass was found in the Tanana River near Fairbanks in central Alaska, nearly 1,700 kilometers (1,100 mi) from the nearest ocean habitat. Belugas sometimes follow migrating fish, leading Alaska state biologist Tom Seaton to speculate that it had followed migrating salmon up the river at some point in the prior fall.
Belugas are highly sociable whales. Groups of males may number in the hundreds, while mothers with calves generally mix in slightly smaller groups. When pods aggregate in estuaries, they may number in the thousands. This can represent a significant proportion of the entire population and is when they are most vulnerable to hunting.
Pods tend to be unstable, meaning that they tend to move from pod to pod. Radio tracking has shown that belugas can start out in a pod and within a few days be hundreds of miles away from that pod.
Mothers and calves form the beluga's closest social
relationship. Calves often return to the same estuary as their mother in the summer, meeting her sometimes even after becoming fully mature.
Belugas can be playful; they may spit at humans or other whales. It is not unusual for an aquarium handler to be drenched by
a beluga whale. Some researchers believe that spitting originated with blowing sand away from crustaceans at the sea bottom.
Unlike most whales, beluga whales are capable of swimming backwards.
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