The need to protect aquatic animals is now more crucial and urgent than ever as a new study by the International Union for the Conservation of Nature (IUCN) reveals that one in four of the world's sharks and rays face extinction.
The study, published in the journal eLife Jan. 21 is the first worldwide assessment of the extinction risks of sharks, rays and related species. More than three hundred researchers coming from 64 different countries have worked together to examine the conservation status of more than 1,000 shark, ray and chimaera species.
"Until now, nobody has done a systematic unbiased study of all the habitats and all the species in the lineage," Nick Dulvy, co-chair of the IUCN Shark Specialist Group (SSG) and Canada Research Chair at Simon Fraser University in British Columbia, told The Scientific American. This was the first time, Dulvy said, the SSG researchers decided to "stitch together all of these jigsaw pieces to see what the big picture is across the world's oceans."
The researchers found that more than 30 percent of the 1,041 known species of sharks, rays and chimaera are threatened, near threatened, vulnerable to extinction and endangered, and only 23 percent of these chondrichthyan (cartilaginous) fishes are considered safe, making them more vulnerable to extinction than most other animals in the world.
"Our analysis shows that sharks and their relatives are facing an alarmingly elevated risk of extinction," Dulvy said. "In greatest peril are the largest species of rays and sharks, especially those living in shallow water that is accessible to fisheries."
The IUCN said that overfishing has endangered the species with the sharks and rays targeted for their meat, gills and fins. They are also intentionally killed because of the perceived danger that they bring.
The researchers also noted that there is currently a shortage of efforts in protecting sharks and rays. "Despite more than two decades of rising awareness of chondrichthyan population declines and collapses, there is still no global mechanism to ensure financing, implementation and enforcement of chondrichthyan fishery management plans that is likely to rebuild populations to levels where they would no longer be threatened," the study, which was published in the journal eLife, read.
