Why is the Blue Whale an endangered animal?
$$$$$ Mark $$$$$
Even though they are the largest animal on Planet Earth, Blue whales are
very fast whales. So in the early days of whaling, when the whaling ships
depended on sail or steam for power, very few blue whales were killed.
During the 1930's some fast diesel-powered whaling ships were built and
blue whales began to be killed in large numbers. Then during WWII whaling
stopped for a while, but after the war, the US actually helped Japan build
a modern, fast whaling fleet. Norway and several other countries did the
same, and by the late 1950's tens of thousands of blue whales were killed
each year, until by the early 1960's they were almost all gone. The only
way they knew that almost all the blue whales had been killed was a
measurement called "catch per unit of effort" or CPU. In other words, when
they couldn't find any more, they figured they must have killed nearly all
of them. Blue whales don't reproduce very fast, so it's possible that they
haven't increased their numbers much since the 1960's. That's why they are
considered endangered.
Howard Garrett
Orca Network
Greenbank WA
(360) 678-3451
www.orcanetwork.org
howard@orcanetwork.org
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