Sharks vanishing from coral reefs
doi:10.1038/nindia.2020.119 Published online 31 July 2020
Sharks are absent on many of the world’s coral reefs, an international research team that surveyed reefs across the globe has found1.
The survey, the researchers say, reveals an alarming global loss of these iconic species, which are important food resources, tourist attractions and top predators on coral reefs. They say destructive fishing practices, such as the use of longlines and gillnets, have driven the sharks literally to extinction in many of the reefs.
Over four years, the scientists, including Venkatesh Charloo from Coastal Impact, a non-profit in Goa, India, captured and analysed more than 15,000 hours of video from surveys of 371 reefs in 58 countries, states and territories around the world.
The survey sighted 59 shark species. However, no sharks were detected on any of the reefs of six nations or territories: the Dominican Republic, the French West Indies, Kenya, Vietnam, the Windward Dutch Antilles and Qatar. This indicates an alarming decline.
The researchers say shark sanctuaries can check such a decline. A nation with a shark sanctuary (that is, areas where there is no targeted catch or any trade in sharks or shark products) supported a 50 per cent higher relative abundance than nations without sanctuaries. Nine nations with shark sanctuaries are globally and regionally important refuges for reef sharks, they found.
This survey of sharks on coral reefs can help develop long-term conservation plans for protecting the reef sharks that remain, the researchers add.
1. MacNeil, A. M. et al. Global status and conservation potential of reef sharks. Nature. (2020) doi: 10.1038/s41586-020-2519-y