Sharks in Peril

Julia Baum is a brand-new face around the campus of Scripps Institution of Oceanography at UC San Diego, but the marine ecologist's name and research on coastal and open-ocean sharks are getting worldwide attention.

At a press conference organized at the annual gathering of the American Association for the Advancement of Science (AAAS) in Boston in February, Baum described research she and her colleagues recently conducted at Dalhousie University in Canada on the cascading effects of shark depletion in ocean ecosystems, a study published last year in the journal Science.

Baum, who joined Scripps Oceanography in October, described to scientists and journalists threats to several large shark species as a result of a rising demand for shark meat and fins, recreational shark fishing and depletion as a result of bycatch. Some species, such as the scalloped hammerhead shark, have seen their numbers dwindle drastically in recent years.

The news was carried in major news outlets across the world, from the BBC to National Geographic to the New Zealand Herald and the South China Morning Post. During the press conference, Baum stressed the need for more effective management and conservation efforts.

"Our oceans are being emptied of sharks and the scale of the problem is global. If we carry on without doing anything about it we are looking at a high risk that some of these (species) could be extinct within our lifetime," Baum, a postdoctoral researcher at Scripps and a member of the World Conservation Union's (IUCN) shark specialist group, told the United Kingdom's Daily Telegraph. "On the high seas there are no catch limits. It's a free-for-all. Over the last decade conservation concerns have been mounting. Now we need to convert that into action to introduce effective measures that are strictly enforced."

At Scripps, Baum will work with Stuart Sandin of the Scripps Center for Marine Biodiversity and Conservation and others to seek a better understanding of the role of sharks in ecosystems and the consequences of losing them. She will investigate shark data obtained by Sandin and his colleagues during expeditions to the central Pacific s Line Islands coral reefs. (See news release on the Line Islands research papers: http://scrippsnews.ucsd.edu/Releases/?releaseID=883)

"The question of ecosystem consequences of losing sharks is pretty difficult because of the complexity of oceanic food webs and the difficultly of studying these apex predators," said Baum. "So the idea for my research at Scripps is to try to nail down this question specifically for coral reef sharks and define the role they play in those ecosystems."