Tuesday, March 07, 2006

Science News: Deep Sea Lacks Sharks

Ocean depths beyond 2,000 metres (6,500 feet) are almost devoid of sharks, a finding that is grim news for these threatened fish, according to a recent study.

An international team of researchers used deep-sea trawls, baited hooks and baited cameras to see where sharks live, testing depths in the Atlantic, Pacific and Indian oceans and Mediterranean Sea from 471 to 5,900 metres (1,530 to 19,175 feet).

Sharks were generally seen or caught at up to 2,000 metres (7,500 feet), but beyond this depth, the numbers were negligible. The deepest specimen was a species called a leafscale gulper shark, caught at 3,280 metres (10,660 feet).

Leafscale Gulper Shark

This means that there are no reserves of sharks living in the abysses - rarely explored depths that are beyond 3,000 metres (9,750 feet) and comprise 70 percent of the oceans' volume.

As a result, almost all sharks are within reach of modern deep-sea trawlers, which can net fish to a depth of up to 2,300 metres (7,475 feet)...

LINK: FULL STORY @ Discovery

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