November 22, 2010

Shark Populations Dwindling In The Atlantic

According to a new report, at least 1.3 million sharks were harvested from the Atlantic in 2008 by industrial-scale fisheries unhampered by catch or size limits.

The study, which was released by advocacy group Oceana, said the actual figure may be higher due to under-reporting.

Oceana released the report at a meeting of the International Commission for the Conservation of Atlantic Tunas (ICCAT).

The 48-member ICCAT is responsible for ensuring that commercial fisheries are sustainable.  It has the authority to set catch quotas and restrictions.

Marine biologists say that many species of high-value sharks are in more desperate situations than the Atlantic bluefin tuna, which has controlled the spotlight of threatened ocean species.

"Sharks are virtually unmanaged at the international level," said Elizabeth Griffin Wilson of Oceana. "ICCAT has a responsibility to protect our oceans' top predators."

The U.N. Convention on the Law of the Sea says that international bodies must manage "highly migratory" sharks.

Three-quarters of the 21 species found in the Atlantic are classified as threatened with extinction.

According to the International Union for the Conservation of Nature (IUCN), North Atlantic populations of the oceanic white tip have declined by 70 percent, and hammerheads by over 99 percent.

Other species have also been overexploited, and may be teetering on the brink of viability.

Many are fished for their fins and then tossed, dead or dying, back into the sea once the choice morsels have been sliced off.

The practice is prohibited, but loopholes in regulation have allowed the ban to be avoided.

Oceana and several conservation groups have called upon ICCAT to set catch quotas and other protective measures for these and other vulnerable sharks.

The U.S. has proposed requiring that all sharks be brought back to shore whole, which would help scientists measure population levels.

Japan is now urging ICCAT to prohibit fishing of the oceanic white tip.  The country stopped a drive earlier this year to protect four threatened shark species under the U.N. Convention on International Trade in Endangered Species (CITES).

The head of the Japanese delegation said in an opening statement that the initiative "is an example showing our commitment for conservation of shark resources."

Sharks have been at the top of the ocean food chain for hundreds of millions of years.

However, the consummate predators are especially vulnerable to industrial-scale overfishing because they mature slowly and produce new offspring.

"The classic fisheries management approach of 'fishing down' a given population to its so-called maximum sustainable yield, and then assuming it can recover, does not work for sharks," said Matt Rand, a shark expert at the Washington-based Pew Environment Group.

Every year, tens of millions of the open-water hunters are extracted from global seas.

Regional studies have shown that when shark populations crash, it impacts throughout the food chain, often in unpredictable and harmful ways.


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