Ocean warming
Coral death in the Caribbean is worse than ever before
According to researchers, corals are currently dying off the coast of Mexico on a large scale. photo
© Lorenzo Álvarez-Filip/-/dpa
Corals live in communities with algae. However, if it gets too warm, they will reject them – and lose their color. In the worst case, the corals die – like now off the coast of Mexico.
“What our tests and analyzes show is impressive. I’ve never seen anything like it,” said the expert from the German Press Agency after his most recent dive in Puerto Morelos, near the holiday resort of Cancún. As a result of climate change, sea temperatures of up to 33 degrees Celsius were recently measured there, three degrees above the historical average. The corals were exposed to the high temperatures for up to 20 weeks. This stress makes it difficult for them to recover. Many have already died.
Other coral reefs also affected
Bleaching is the fading of the often colorful corals. They live in a community with different colored algae for mutual benefit. However, at high temperatures, the corals reject the algae – and thus lose their color. They no longer grow and are less able to defend themselves against enemies and competitors. If the microalgae return within a certain time because the water temperatures drop again, the coral can recover – otherwise it will die.
The so-called cnidarians are also increasingly bleaching on other coral reefs in the Atlantic and off Huatulco on the southern Mexican Pacific coast. Coral bleaching has already been reported off Florida, Cuba, Belize, Panama, the Bahamas, Antigua, the US Virgin Islands, Colombia and Puerto Rico, according to the Global Coral Reef Monitoring Network (GCRMN).