The Israeli Nature and Parks Authority (NPA) announced on November 5 that researchers and marine ecologists in the country have discovered severe coral bleaching in the Gulf of Aqaba, located in the northern Red Sea, off the coast of Eilat, Israel.
In a publication in the journal Ecology and Environment, scientists from the NPA and the Inter-University Institute for Marine Sciences in Eilat reported findings indicating that for the first time in history, corals in the Gulf of Aqaba have lost their natural color due to record-high sea temperatures during the previous summer. This phenomenon is a direct consequence of extreme heat waves, with water temperatures reaching 31.9 degrees Celsius and daily highs exceeding 30 degrees Celsius for two consecutive months of summer.
Corals in the Ras Mohamed Nature Reserve in Egypt on the Red Sea. (Photo credit: AFP/TTXVN).
The phenomenon of coral bleaching does not mean that corals die immediately; however, it makes them vulnerable and can lead to gradual death because they are unable to perform photosynthesis due to the breakdown of the symbiotic relationship with zooxanthellae algae living within their tissues. When water temperatures exceed dangerous thresholds, this symbiosis is disrupted, causing the algae to be expelled from the coral. This reduces the corals’ survival capability and weakens the already rich and diverse marine ecosystem.
According to researchers, corals in the Gulf of Aqaba have long been known for their ability to withstand higher-than-normal sea temperatures, thanks to natural selection over centuries. The Gulf of Aqaba’s location at the Bab el-Mandab strait, the gateway between the Red Sea and the Indian Ocean, has allowed corals here to develop resilience to higher temperatures compared to other regions worldwide. However, it is concerning that over the past summer, the coral reefs near Eilat experienced accumulated heat levels 3.75 times higher than the threshold that triggers severe bleaching events in coral reefs globally.
This implies that despite the natural resilience of the corals in the Gulf of Aqaba, the sudden spike in temperature has exceeded the limits they can endure. This is an alarming sign, indicating that even with long-term adaptations, these coral reefs are not immune to climate fluctuations.
Currently, the Israeli Nature and Parks Authority (NPA) has begun conducting surveys to assess the extent of coral bleaching and monitor the recovery process and mortality rates of affected coral reefs. This will provide critical data for scientists to develop protective measures and restore marine environments against the impacts of climate change.
The Red Sea, especially the Gulf of Aqaba, has long been known for its incredibly rich marine ecosystem, home to many unique marine species. However, uncontrolled temperature changes, particularly extreme heat waves such as this past summer, have been causing severe impacts on the survival of coral species, as well as affecting other marine organisms.
These studies not only serve as a warning for the Red Sea but also signal serious concerns for marine ecosystems worldwide. Climate change is gradually altering living conditions, putting coral species and marine life in jeopardy. Coral bleaching may be indicative of broader changes affecting marine food chains, ecosystems, and even industries dependent on these resources.
