16 February 2010

Migratory sharks need global protection: U.N.

Cosmos Online
The first global agreement to conserve migratory sharks, including great white and whale sharks, was signed in Manila, but no management plan was put in place.
Shark fins

Workers prepare shark fins for sale in Hong Kong, where it is considered a delicacy. Credit: AFP

MANILA: The first global agreement to conserve sharks was signed last week in Manila, but no management plan is in place. Migratory sharks, including great white and whale sharks, are under serious threat from fisheries and finning.

“Sharks are one of the most seriously threatened taxonomic groups in the world,” said UK-based Sarah Fowler, co-chair of the Shark Specialist Group, which is part of the International Union for the Conservation of Nature (IUCN).

The IUCN Red List 2010 estimates that 17% of the 1,044 known shark species are threatened. Of these, “the migratory sharks are the most vulnerable to extinction,” said Fowler.

Sharks travel large distances, cross boarders

Migratory sharks travel large distances and cross national boundaries, such as the whale shark, which travels 13,000 km across ocean basins – but currently there is no standard for international management.

To address the situation, an international meeting was held in Manila in the Philippines, spearheaded by the United Nations Environment Program and the Conservation of Migratory Species (CMS) secretariat.

“This negotiation is the first global agreement to conserve sharks … and in fact any migratory animal on this scale,” said Germany-based Elizabeth Maruma Mrema executive secretary of the CMS.

All countries can manage and use the natural marine resources within 200 nautical miles from their coastline. But international waters are mainly unregulated, and boats in international waters are under the regulation of their home state.

Seven species of shark

Delegates from 10 countries signed a Memorandum of Understanding including the Philippines, Senegal, Togo, US, Republic of Congo, Costa Rica, Ghana, Guinea, Liberia and Palau.

There are seven species of sharks listed: the great white, basking, whale shark, porbeagle, spiny dogfish, and both shortfin and longfin mako sharks.

The associated Conservation and Management Plan was not agreed upon at the meeting in Manila, meaning that there is no scientific standard from which the Memorandum of Understanding is based. Measures could include more scientific research, better education and law enforcement.

“Although not legally binding, this Memorandum of Understanding actually has a better chance of helping to save the species than a legally binding document … this is because action will happen now when it is most needed,” says Maruma Mrema.

Other non-legally binding CMS agreements such as that for the sea turtle have been relatively successful at conserving migratory species.

“Compared to fish, sharks – and I include all sharks and rays – are more similar to mammals in that they tend to grow quite slowly, mature quite late and when they do mature, most of them give birth to only a small number of pups,” Fowler said.

“In some cases, they may only reproduce once every few years.”

Shark are apex predator, indicate eco-health

Sharks are a good bio-indicator of the health of the environment. They are the first species to decline if there is heavy exploitation pressure on an ecosystem.

“Sharks have adapted to be apex predators with very few natural enemies, so they don’t need to have many young to replace themselves,” said Fowler.

“Fisheries are the main threat for migratory sharks because the current fisheries catches, either as by-catch or target catch, are higher than the shark’s reproductive capacity,” said Fowler.

Fisheries and shark fin soup has devastating toll

Up to 900,000 metric tons of sharks are caught every year, according to the Food and Agricultural Organisation. However, this doesn’t take into account unreported data which could be as much as twice this amount alone, according to Fowler.

The most devastating effects on nomadic shark populations occur mostly in Asia, where sharks are killed for their fins to make shark fin soup. All migratory sharks are at risk of this fate.

Over 20 countries around the world have banned finning – including some Asian countries – but the practice continues. In Australia, it is illegal to catch sharks simply for their fins.

Shark fins small and valuable

“Because the value of the fins is so high, particularly in unregulated fisheries, only the fin is cut off the shark and the rest of the shark is discarded while it’s alive,” says Alexia Wellbelove, Program Officer from the Humane Society International in Sydney, Australia.

“The problem is that it’s possible to store a lot more fins than shark bodies, so each boat has a devastating effect on shark populations.”

As of January, killing, injuring or capturing the porbeagle, shortfin mako and longfin mako in Australia is illegal. However, legislative amendments are proposed to enable recreational fishing of mako sharks to continue.

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