Beluga whales are at the top of the food chain. A nice distinction, but it also means they acquire the sum total of toxins acquired by organisms all the way down the chain because these toxins such as PCB and heavy metal poisoning don't break down. Belugas, in fact, are so full of contaminants, when they are found beached they qualify as a toxic biohazard.
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Beluga whales are at the top of the food chain. A nice distinction, however, it also means they acquire the sum total of toxins in the organisms in that chain. Since PCBs and heavy metals don't break down in any organism they accumulate instead.
So when a Beluga eats a salmon that ate a crustacean that grubbed on some plant, all the PCBs and heavy metals that these organisms absorbed end up in the beluga.
Belugas, in fact, are so full of contaminants, when they are found beached they qualify as a toxic biohazard.
Submarines have been using low and mid-frequency active sonar technology, a deafening soundwave that is dangerous even 300 miles from it's source. Some mid-frequency sonar systems can put out over 235 decibals, which is about as loud as a rocket launch.
Animals for hundreds of miles literally jump out of the ocean to try to avoid the sound. The damaging effects vary, bet are akin to decompression sickness causing internal bleeding and bursting organs including lungs and eardrums. When beached dolphins are reported this sonar technology is rarely mentioned in the news, although the link has been demonstrated.
What can you do? learn more here
(update: court blocks sonar 7/6/06)
The harmless whale shark holds the title of largest fish, with the record being a 59 footer captured in Thailand in 1919.
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