Crisis on the Mexican Caribbean Reef: Coral Bleaching Devastation

The Mesoamerican reef system, the world's second-largest coral barrier, is under increased stress due to global warming, climate change, and rising water temperatures. The Puerto Morelos Reef National Park, part of this barrier known as the Great Western Atlantic Reef Belt, is particularly affected.

In Puerto Morelos, sea temperatures last year were 3 to 4 degrees above normal, especially during the summer. "The heat has caused bleaching in the ecosystem. The small macroalgae within the corals separate, lose energy, and become transparent," explained a reef systems researcher.

This issue is not confined to the Caribbean Sea or Mexico, but it is a global problem. Between July and October of 2023, aggressive temperatures resulted in widespread coral deaths. According to the US National Oceanic and Atmospheric Administration (NOAA) and the International Coral Reef Initiative (ICRI), coral reefs worldwide are currently experiencing another episode of coral bleaching. Such episodes were once rare, but this is the second significant occurrence in the past decade and the fourth since 1982. By 2050, it's predicted that 90% of the world's coral reefs will experience annual bleaching.

In the Mexican Caribbean, the phenomenon has heavily impacted shallow reef lagoons. The sea in protected areas warmed significantly, causing high mortality rates in staghorn coral, fire corals, and lettuce corals. In deeper locations, about 30 meters down, the reef landscape was entirely white.

"In areas like Puerto Morelos and Tulum, the reef lagoon's lack of movement and shallow depth greatly affected the corals. In contrast, deeper areas with some current were less impacted; Cozumel and Akumal were the least affected," the researcher noted. "Regrettably, in Puerto Morelos, over 90% of the staghorn corals died. The mortality rates were similar for lettuce coral and fire coral species in other parts of Quintana Roo."