Sharks and rays are key functional components of coral reef ecosystems and cannot be replaced by other species.

Almost two-thirds of sharks and rays living in coral reef areas around the world are threatened with extinction. If nothing is done, this could have potentially dire consequences for coral reef ecosystems.

This is stated in a study published in the journal Nature. The main reason for the increased risk of extinction, experts say, is overfishing, which is exacerbated by climate change and the degradation of the environment of sharks and rays – coral reefs.

There are 30 families, 59 genera and 134 species of reef sharks and rays. Almost two-thirds of them (59%) are under threat of extinction. In particular, five species of sharks, as well as nine species of “rhinoceros rays” are included in the endangered list.

It is emphasized that sharks and rays are key functional components of coral reef ecosystems and cannot be replaced by other species. The disappearance of such species will have cascading effects in the food chains of other species.

The consequences will affect not only coral reef ecosystems, but also people: coral reefs provide livelihoods and food security for more than half a billion people living in coastal regions.

The population of these reef-dwellers has been in decline for over half a century, but the largest decline occurred before 2005.

Scientists have concluded that reef sharks face the greatest threat in the Western Atlantic and parts of the Indian Ocean. And for stingrays, there is a threat in the waters of Southeast Asia and also in the Indian Ocean.

What is known about the threat to coral reefs

As reported, the increase in sea temperature due to global warming caused by the burning of minerals has led to the mass death of corals in recent years.

The Great Barrier Reef is to be added to the list of world heritage sites that are “in danger”, according to a new report by a group of scientists published in late 2022 with the support of the United Nations. Scientists have said the reef faces serious threats from the climate crisis and that action to save it must be taken “as a matter of priority”.

Scientists predict that 70% to 90% of all living coral in the world will disappear within the next 20 years. In particular, the Great Barrier Reef has experienced multiple devastating mass bleaching events since 2015 caused by extremely high ocean temperatures.

An earlier study showed that sharks have declined on almost every fifth coral reef in the world. Researchers believe that the decline in shark numbers, caused mainly by overfishing, could have dire consequences for corals struggling to survive a changing climate.