| 1. |
Beluga
whales are toothed whales from the family Monodontidae.
The only other member of this family is the narwhal.
The English name "beluga" comes from
the Russian word belukha, which means "white."
Belugas are also known as white whales.
|
| |
|
| 2. |
Beluga whales are entirely arctic and subarctic.
Typically, they inhabit shallow coastal waters of
the icy Arctic Ocean and its adjoining seas, but
during the summer many populations may also congregate
in warmer freshwater estuaries and river basins.
|
| |
|
| 3. |
At birth, beluga calves are generally dark gray.
They gradually lighten with age, and upon reaching
maturity (about eight to nine years for males),
attain the white coloration characteristic of adult
belugas. The white coloration protects belugas from
predators by camouflaging them among the icebergs
and ice floes of northern seas. |
| |
|
| 4. |
Beluga
whales lack dorsal fins, but have a low dorsal ridge.
Without a dorsal fin, a beluga can more easily swim
beneath extensive ice sheets and locate breathing
holes. |
| |
|
| 5. |
Beluga
whales are among the few whales that have unfused
neck vertebrae. This feature makes their necks quite
flexible and gives their heads a wide range of motion. |
| |
|
| 6. |
Beluga
whales face a number of environmental threats. Industrial
run-off in the St. Lawrence River has resulted in
high levels of PCBs, heavy metals, and other toxins
in the water. The toxins enter the food chain through
single-celled organisms and become concentrated
in the bodies of large carnivores. The deaths and
strandings of many belugas are thought to be linked
to these toxins. |
