The great white shark is threatened by extinction in the Mediterranean Sea

The great white shark is being hunted to extinction in the Mediterranean, while angel sharks have disappeared altogether from the North Sea according to a report from the UN's Food and Agriculture Organisation (FAO) meeting in Rome.

Although listed as an endangered species since 1983, the great white is legally protected only in Malta. The UK government promised to protect angel sharks in 2001 but, six years on, nothing has been done and they are now classified extinct.

World fisheries experts are seeking urgent protection measures and their study shows the crisis facing fish stocks of every sort all over the world.

The situation of the sharks is particularly grim. The reason is closely related to their well-known peculiarities - the fact they constantly roam the seas, have few offspring, and that their fins are a prized ingredient in a Chinese soup.

Sharks can live up to the age of 30, and many species only begin reproducing when they are aged six or more. The young remain inside the mother until they have hatched from the eggs. It means that when young females are caught in trawlers' driftnets - often as "bycatch" when the intended catch is sardines or anchovies - their whole lineages are wiped out.

"The number of offspring of a shark is very small," said Jorge Csirke, chief of Fisheries Management and Conservation at FAO, "and so if you kill a female you kill all her possible offspring. If you kill her early in her life, she hasn't reproduced at all." Sharks are especially vulnerable for other reasons, too, Mr Csirke explained. "They spend a lot of their lifespan in the high seas, outside the exclusive economic zones around countries, and in the high seas you don't have protection. No regional bodies are taking responsibility for them."

Another factor leading to their numbers falling - in quantities that are almost impossible to measure accurately - is the growing appetite for the cartilage that is the key ingredient in shark fin soup. To feed that lucrative market, many fishermen engage in what is known as "finning", stripping the fins from the shark then tossing them back in the sea to die of their wounds or be eaten alive. The practice has been declared illegal in several countries including Brazil, South Africa and the USA but it remains widespread and largely unmonitored.

"The fins fetch such a high price," says Mr Csirke, "if you go out with a small boat you don't want the whole fish on board, because what you can get for the fins is far more than you can get for the rest of the carcass."

According to FAO, finning causes the death of tens of millions of sharks every year, "directly threatening rare and vulnerable shark species and indirectly impacting other commercial species due to the effects of the removal of top predators from these food webs."

But despite the alarm over the rapid destruction of the world's sharks, governments even in Europe are slow to act. Angel sharks, abundant in coastal waters not long ago, have disappeared from the European seas and have been officially declared extinct in the North Sea by the International Council for the Exploration of the Sea.

The angel shark was nominated for strict legal protection in British waters in 2001. Six years on, the nomination is still in limbo and the angel shark still has no protection.