MercoPress. South Atlantic News Agency

Hammerhead shark joins the red list of globally endangered

Populations of tiger, bull, dusky and other sea sharks have plummeted by more than 95% since the 1970s, according to an expert from the World Conservation Union. But ongoing efforts to identify shark “hotspots” across the oceans could help improve their chances of survival in future.

At particular risk is the scalloped hammerhead shark, whose young swim mostly in shallow waters along shores all over the world to avoid predators. This species will be listed on the World Conservation Union's (IUCN) 2008 Red List as "globally endangered" as a result of over-fishing and high demand for its fins, says Julia Baum, a member of the group's shark specialist group. Hammerhead sharks are among the most endangered species because their fins are highly prized for shark-fin soup, an Asian delicacy. They tend to move in packs and congregate in specific areas such as the Galapagos Islands and Costa Rica. Fishing for sharks in international waters is unrestricted, says Baum, who supports a recently adopted UN resolution calling for immediate limits on shark catches and a ban on shark finning – when fishermen chop the fins off the animals and dump them back into the sea. But hope for the future is offered by ongoing efforts to track sharks in their natural habitats. Peter Klimley, director of the Biotelemetry Laboratory at the University of California, Davis, is using electronic tags to monitor the movement of scalloped hammerhead sharks. His work has already revealed hammerhead "hotspots" where the sharks spend most of their time. In between these hotspots are so-called "superhighways" – channels that sharks use to move quickly from one hotspot to another. "Enforcing reserves around these areas will go far to protecting these species, and will provide the public with places for viewing sharks in their habitat," says Klimley. Salvador Jorgensen of Stanford University, also in California, has been tracking great white sharks off the coast of central California. Through the Tagging of Pacific Predators programme, he and colleagues have identified two tropical hotspots, between Hawaii and Mexico, where great whites like to spend the winter. One of these, some 2000 kilometers off the coast has been dubbed "white shark café" by the researchers. "We started calling it the café because that is where you might go to have a snack or maybe just to 'see and be seen'. We are not sure which," says Jorgensen. Great whites are currently listed as "vulnerable to extinction" by the IUCN and last year the same organization put the great hammerhead - the largest of all nine species of hammerhead – on its endangered list. In September 2007, the IUCN announced that populations of shark in the eastern Atlantic had probably crashed by 80% over the last 25 years. Saving shark species from extinction could have knock-on benefits for fishing industries. Last year, research revealed that the demise of the US shellfish industry can be traced to the way humans have slashed shark populations.