Wildlife & Biodiversity

Over 390 species of sharks, rays, chimaera in danger of extinction: Study

Overfishing, the biggest threat, is compounded by loss and degradation of habitat, pollution as well as climate change 

By Madhumita Paul
Published: Wednesday 08 September 2021
37.5 per cent sharks, rays and chimaeras species are threatened, warns study
Photo: NOAA Ocean Exploration & Research / flickr

Over 37 per cent of the world’s world’s sharks, rays and chimaeras are facing extinction due to overfishing, compounded by loss and degradation of habitat, climate change and pollution, warned a new study

As many as 220 of the total 661 species of rays are threatened, followed by sharks (167 of 536) and chimeras (four of 52), according to the extensive survey done from 2013 to 2021. 

The chondrichthyan fishes that faced extinction more than doubled since the last global survey done in 2014 that showed 181 of a total of 1,041 species were threatened. 

Andy Cornish, who leads the global shark and ray conservation programme of World Wide Fund for Nature, said:

The alarm-bells for sharks and rays could not be ringing louder. The sheer number and diversity of these animals facing extinction is staggering. The good news is that solutions to this crisis do exist. Governments and the regional fisheries management organisations, which manage fishing in the high seas, must act now and boldly to recover the most threatened species before it is too late.

One ray species, the Java stingaree (Urolophus javanicus), may have already gone extinct according to the reclassification of threatened species by the International Union for Conservation of Nature (IUCN) earlier this year.

The international organisation changed the status of the species to ‘Possibly Extinct’ from ‘Critically Endangered’ in 2006 in its list of threatened species. This unique endemic species has not been seen since the end of the 19th century when it was discovered. 

Overfishing, mainly by industrial-scale fisheries, is the main threat for all the 391 threatened chondrichthyan fish species, the study found. Most threatened species are used for food consumption by human beings.

Habitat loss and degradation of habitat, in addition to overfishing, caused nearly a fifth of the species to be threatened, according to the report. 

The researchers called for science-based limits on fishing, effective marine protected areas, among other approaches to minimise mortality of threatened species. 

The study was published in the journal Current Biology September 6, 2021. It was carried out as part of the Global Shark Trends Project, a collaboration of the IUCN shark specialist group, Simon Fraser University, James Cook University and the Georgia Aquarium.

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