Asian nations on Tuesday blocked U.S.-backed proposals to protect the heavily fished hammerhead and oceanic whitetip sharks on concerns that regulating the booming trade in fins could hurt poor coastal nations.

A hammerhead shark swims in a tank at the Georgia Aquarium in Atlanta. A U.S.-backed proposal to protect the heavily fished hammerheads was narrowly rejected Tuesday amid concerns that curbing the trade in shark fins could hurt poor nations. (John Bazemore/Associated Press)

However, a committee at the 175-nation Convention on International Trade in Endangered Species approved regulating the trade in the porbeagle shark, which is prized mostly in Europe for its high-valued meat. Controls on the spiny dogfish shark, a key ingredient in fish and chips, were also being considered at the meeting in Doha, Qatar.

Japan, which successfully campaigned against an export ban on Atlantic bluefin tuna and regulations on the coral trade, led the opposition to the hammerhead and oceanic whitetip shark proposal at CITES. It didn't speak on the porbeagle.

The hammerhead and whitetip sharks are heavily fished for their prized fins, with the carcasses often discarded.

China, Indonesia and other countries that benefit from the trade in fins joined opposition to the proposals, agreeing that trade restrictions were not the answer and would be difficult to apply.

"This is not about trade issues, but fisheries enforcement," Masanori Miyahara, chief counsellor of the Fisheries Agency of Japan, told delegates. "Poaching is a big problem. Small-scale long-liners are chasing sharks all over the world."

The United States, supported by Europe, Australia and many Arab countries, argued that the unregulated trade has led to widespread illegal fishing and has caused the populations of the endangered scalloped hammerhead, great hammerhead and the threatened smooth hammerhead to plummet by as much as 85 per cent.

"The greatest threat to the hammerhead is from harvest for the international fin trade, and the fin of the species is among [the most] highly valued of the trade," said Tom Strickland, assistant U.S. secretary of the interior for fish, wildlife and parks.

Shark fin soup is a much-prized delicacy in China.

Other sharks threatened

Oceanic whitetip sharks face similar threats and their numbers are down 60 to 70 per cent, Strickland said.

The hammerhead protection measure was only narrowly rejected by the UN committee, failing by five votes to take the necessary two-thirds of majority. The whitetip proposal fell nine votes short of approval.

Strickland said the proposals may be revived at the larger, plenary meeting that begins Wednesday.

"It's disappointing we didn't get the two-thirds, but that is the way the rules are set up," Strickland said. "We are going to continue our efforts both here and going forward to put the necessary protection in place for these shark species."

The tiny Pacific nation of Palau, which last year created the first-ever shark sanctuary, joined the Americans in introducing the shark proposals. It called on countries to protect the species so they can be fished well into the future.

"We must preserve for our children these amazing species," said Harry Fritz, Palau's minister of natural resources, environment and tourism, adding that his country supports the protection of other shark species as well.

CITES was due to take up European proposals later in the day for protections of the porbeagle shark, which is killed for its meat, and the spiny dogfish shark — a chief ingredient of fish and chips and fish sticks.

Conservationists were outraged and disappointed by the rulings, since it came after a string of defeats on marine species, including a proposal last week on a shark conservation plan. Japan and China led efforts to kill that proposal as well.

"Today is a huge loss for the oceans. This is a case of politics prevailing over science," said Elizabeth Griffin, fisheries campaign manager for the environmental group Oceana. "The world failed to stand up today to protect some of the ocean's top predators."

Jupp Baron Kerckerinck zur Borg, president of the Shark Research Institute based in Millbrook, N.Y., acknowledged he was "very disappointed and frustrated right now."

"Japan has been voting the shark proposals down because they are catching them, Singapore voted them down because they make money selling the fins and China makes money because they eat them," he said.

"How can we win?"

The Pew Environmental Group said the sharks are especially vulnerable to overfishing because they are slow-growing and have low reproductive rates. Fishermen, both industrial and small-scale and many operating illegally, slice off the fins and throw the carcasses back into the ocean.

Shark fin soup has long played a central part in traditional Chinese culture, often being served at weddings and banquets. Demand for the soup has surged as increasing numbers of Chinese middle-class families become wealthier.