11/05/2011

Beluga Whale

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Beluga or "white whales" are not born white. They are grey at birth and get lighter and lighter until at about age six they are completely white. Belugas are one of the three whales that spend all their lives in arctic waters. The other two are the bowhead and the narwhal. Beluga are special among all whales because they can turn their heads. Maybe this is so that they can communicate with each other better! Beluga are very social and make a wide variety of sounds. A group of beluga can be loud! They have been nick-named "sea canaries." Beluga use sound to help them find their prey. They send out a sound which bounces off things in the water and allows them to hear how far away something is. This is called "echolocation." Beluga will work together using this and other techniques to herd fish into shallow water. It has also been reported by native people that beluga whales help each other give birth! They use many subtle forms of communication including a wide variety of facial expressions. Unlike some other whales, beluga have good vision.What they don't have is a dorsal fin, earning them the name "delphinapterus" or dolphin-without-a-wing.



19th Century Naturalist
Edward Nelson Recounts:

"In January,  1879, while sledging near the mouth of the Kuskoquim River, a considerable number of White Whales were seen one evening among the broken ice near shore.  They were in an irregular school containing twenty or more individuals.  They are seen sometimes in winter off the Yukon mouth when the ice is driven off shore or broken up.
At Point Hope on July 20, 1881, the females were seen swimming up and down the shore singly, each with two or three males keeping close alongside.  Each female was accompanied by a young of the year, which kept close above its mothers back or just behind her.
At Saint Michaels the first ones seen in spring usually arrive between the 5th and l0th of June soon after the ice moves offshore or leaves the inner bays.  This is the spawning time for the herring which swarm along the shore and the White Whales follow them into all the bays and inlets.  On calm June mornings great schools of these whales, numbering from twenty to over a hundred animals, are frequently seen in the bay at Saint Michaels, and their glistening milk-white color shows handsomely against the dark green water.
About the middle of June the first young are seen.  For the first few weeks after their birth they are very small, and have a great bulging forehead, which extends beyond a vertical line from the end of the jaws.  Their color is a dark livid bluish or dull bluish green, so dark that they look almost black when seen at a distance in the water.  They keep close to their mothers, and the latter swim very carefully, the young usually resting on their backs just beside the thin upward extension of the skin, which appears like a false fin.  During the remainder of the season they are generally distributed along the coast.  The closing of the bays and streams by ice the last of October drives them off shore and south each autumn."
BELUGA WHALE
Beluga Whale

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