GLAND, Switzerland, Jan. 21, 2014 /PRNewswire-USNewswire/ -- A quarter of the world's sharks and rays are threatened with extinction, according to IUCN Red List™ criteria, with rays at greater risk than sharks. The findings, published today in the journal eLife, are part of a global assessment of 1,041 species conducted by the IUCN Shark Specialist Group. Ray and sharks are at substantially higher risk than most other groups of animals and have the lowest percentage of species considered safe. Overfishing is the main threat.
"Our analysis shows that sharks and their relatives are facing an alarmingly elevated risk of extinction," says Dr. Nick Dulvy, IUCN SSG Co-Chair and professor at Simon Fraser University. "In greatest peril are the largest species of rays and sharks, especially those living in shallow water that is accessible to fisheries."
Reported shark, ray, and chimaera catches peaked in 2003 and have been dominated by rays for 40 years. Unintentionally caught sharks and rays account for much of the catch, yet developing markets and depletion of targets have made this "bycatch" increasingly welcome.
"We have found thatthe rays -- including sawfishes, guitarfishes, and stingrays -- are generally worse off than the sharks, with five out of the seven most threatened families made up of rays," says Dr. Colin Simpfendorfer, IUCN SSG Co-Chair and professor at James Cook University. "While attention to the plight of sharks is growing, the widespread depletion of rays is largely unnoticed. Conservation action for rays is lagging far behind, which only heightens our concern."
Demand for shark fin soup is a major factor in the depletion of sharks and some rays. Sharks, rays, and chimaeras are also sought for meat, and other products. Safeguards are generally lacking.
"Sharks, rays, and chimaeras tend to grow slowly and produce few young, leaving them particularly vulnerable to overfishing," saysSonja Fordham, IUCN SSG Deputy Chair and president of Shark Advocates International. "Significant policy strides have been made, but effective conservation requires a dramatic acceleration in pace as well as an expansion of scope to include all shapes and sizes of these exceptional species. The need for such action is urgent."