Red Sea 'Super Corals' Face New Heat Stress
Recent bleaching events in Egypt's resilient reefs highlight a scientific debate over whether evolutionary history or water circulation provides the blueprint for coral survival.
Corals in Egypt’s Red Sea, long regarded as "super corals" for their ability to withstand rising temperatures, are showing signs of vulnerability. According to reporting from Wired, a survey led by Mahmoud Hanafy—a professor at Suez Canal University and consultant for the Hurghada Environmental Protection and Conservation Association (HEPCA)—found bleaching across Red Sea corals in 2024. While less than 10% of surveyed colonies in northern areas were affected, bleaching impacted half of the corals further south.
Scientists are currently debating the mechanism behind the region's historical resilience. Eslam Osman, a marine ecologist at King Abdullah University of Science and Technology (KAUST), suggests an evolutionary filter; he posits that corals entering the Red Sea via the Bab al-Mandab Straight had to survive exceptionally warm waters, leaving only heat-tolerant genotypes to spread north.
Conversely, Hanafy argues that water circulation is the primary driver. He explains that vertical mixing in the northern Red Sea brings cooler deep water to the surface, buffering the reefs. Hanafy suggests the 2024 bleaching occurred because the sea remained unusually calm for approximately six weeks, weakening this circulation. HEPCA's report also cites exceptionally low tides in July 2024 as a stress factor.
Despite these events, Wired reports that HEPCA's preliminary estimates show recovery rates between 75% and 88% a year later, a rebound significantly stronger than global averages. To bolster protection, the Egyptian government is establishing new protected areas and partnering with the Global Fund for Coral Reefs and the United Nations Development Program.