Science – Coral die-off in the Caribbean is worse than ever – Knowledge

Puerto Morelos (dpa) – According to researchers, coral reefs are currently dying off the coast of Mexico at an unprecedented rate. Extremely high water temperatures, which can last for weeks to months, have led to severe coral bleaching in the Caribbean as well as in the Mexican Pacific, said Lorenzo Alvarez Felipe of the Academic Unit for Coral Reef Systems at the National Autonomous University of Mexico.

“What our tests and analyzes show is impressive. I have never seen anything like it before,” the expert from the German news agency said after his recent dive in Puerto Morelos, near the resort of Cancun. As a result of climate change, sea temperatures were recently measured as high as 33 degrees Celsius there, three degrees higher than the historical average. The corals were exposed to high temperatures for up to 20 weeks. This stress makes it difficult for them to recover. Many have already died.

Other coral reefs were also affected

Bleaching is the wilting of often colorful corals. They live in a community with different colored algae for mutual benefit. However, at high temperatures, coral rejects the algae – and thus loses its colour. They no longer grow and are less able to defend themselves against enemies and competitors. If the microalgae returns within a certain period of time because water temperatures drop again, the coral can recover, otherwise it will die.

So-called stingrays are also increasingly bleaching other coral reefs in the Atlantic Ocean and off Huatulco on Mexico’s South Pacific coast. Coral bleaching has already been reported off the coasts of Florida, Cuba, Belize, Panama, the Bahamas, Antigua, the US Virgin Islands, Colombia and Puerto Rico, according to the Global Coral Reef Monitoring Network (GCRMN).

© dpa-infocom, dpa:230917-99-223741/3