A major study re-assessing the International Union for the Conservation of Nature (IUCN) Red List status for all sharks, rays and chimaeras reveals that over 1/3 of all these species are now at risk of extinction caused by over-fishing.

Governments and regional fisheries bodies must act now to stop over-fishing and prevent a global extinction crisis.

The experts found that the number of threatened species has doubled since the last global study while the number of endangered and critically endangered species has more than tripled. Three species have been classified as “possibly extinct," not having been recorded for 80 years on average.

All threatened sharks and rays are being depleted by over-fishing, with habitat loss and destruction and climate change compounding the risks, affecting 1 in 3 and 1 in 10 species respectively.

"The alarm bells could not be ringing louder for sharks and rays. We are on the cusp of starting to lose this ancient group of creatures, species by species right here, right now. Starting now, we need far greater action by governments to limit fishing and bring these functionally important animals back from the brink," said Dr Andy Cornish, leader of the global shark and ray conservation program at World Wildlife Fund (WWF).

While the governments in shark-catching countries and regional fisheries management bodies have largely moved in the right direction to address over-fishing over the past decade, they typically fall short of implementing measures to directly control the amount of fishing, such as through catch limits.

The end result – making sharks and rays the second most threatened vertebrate group on the planet – is alarming even if predictable, with too little happening too late.

“At the national level, fisheries and environmental authorities need to work together to stop over-fishing and halt further declines. This is a pivotal moment in time. If we act now, we still have a good chance to save these predators that play such an important role in ocean health," added Dr Cornish.

"However, if the status quo continues with slow incremental improvements in management, nobody should be surprised when shark and ray species start disappearing on our watch. This study is a huge wake-up call! All countries and regional fisheries bodies that catch sharks and rays need to step up and take responsibility," Dr Cornish added.

The most endangered sharks and rays will need recovery plans that reduce mortality from fishing to as close to zero as possible.

For those species that can still sustain fishing, well-enforced science-based catch limits can prevent declines and even lead to recoveries. Where catch limits are not feasible, protecting critical habitats for sharks and rays and reducing incidental fishing mortality (e.g. through catch mitigation measures) can reduce over-fishing.

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