Extinction Sharks

But like other sharks it has fallen victim to fishing and the high value placed on its fins, considered a delicacy in China.

Later this year the scalloped hammerhead will be placed on the World Conservation Union's Red List of threatened species under the heading "globally endangered". The category is only one step below the highest rating of "critically endangered".

Scientists have seen numbers of the creature, which grows up to four metres long and is the best known hammerhead species, dwindle alarmingly in some parts of the world. Declines of 98 per cent have been recorded off the US east coast since the 1970s, and losses of 90 per cent in other areas.

Unlike most other sharks, the scalloped hammerhead swims in large schools which tend to congregate in specific locations, such as the Galapagos Islands and Costa Rica. A fishing vessel stumbling upon one of these gatherings can easily wipe the whole school out.

Experts say the fate of the scalloped hammerhead reflects a looming crisis for many of the oceans' top predators.

A total of 233 types of shark are currently on the Red List, 12 of which are considered "critically endangered". Nine, including the scalloped hammerhead, have joined or will be joining this year. Among them are some well known species, such as the common thresher, the shortfin mako, and the tiger and bull shark.