Tel Aviv: An epidemic that has killed all the black sea urchins in the Gulf of Eilat and other parts of the Middle East threatens to destroy coral reefs in those regions, a study released on Wednesday found.
"This situation is unprecedented in the entire documented history of the Gulf of Eilat," said a team of researchers from Tel Aviv University. The researchers noted that extensive mortality is also occurring in other countries in the region, including Jordan, Egypt, Saudi Arabia, Greece and Turkey.
The TAU findings were recently published in Frontiers in Marine Science and Royal Society Open Science, both peer-reviewed.
Coral reefs act as nurseries and habitats for countless marine species, providing shelter, food, and protection from predators. They also serve as a natural barrier, reducing coastal erosion and buffering against storm damage. Coral reefs also trap carbon that would otherwise be released into the atmosphere, helping mitigate the impact of climate change.
Rising sea temperatures, pollution, overfishing, and human activities pose significant challenges to the survival of the reefs Now, an epidemic killing off sea urchins is also raising a dire threat.
The source of the pandemic is thought to be a pathogenic ciliate parasite that eradicated the entire sea urchin population in the Caribbean in the 1980s, damaging the coral reefs there irreversibly, the researchers wrote.
The current epidemic was first discovered in the Mediterranean but quickly reached the Red Sea, where it is spreading at an unprecedented rate.
Within a few months, the epidemic killed all the black sea urchins in the Gulf of Eilat; they died within two days of falling ill.
Sea urchins are considered essential for the healthy functioning of coral reefs, the study says.
"At first we thought it was some kind of pollution or poisoning or a local chemical spill from the industry and hotels in the north of the Gulf of Eilat, but when we examined additional sites in Eilat, Jordan and Sinai, we quickly realized that this was not a local incident," said Omri Bronstein of Tel Aviv University, who led the study.
"All findings pointed to a rapidly spreading epidemic," he said.
He noted that similar reports are coming in from colleagues in Saudi Arabia.
"Even sea urchins that we grow for research purposes in our aquariums at the Interuniversity Institute [for Marine Sciences in Eilat], and sea urchins at the Underwater Observatory Marine Park in Eilat, contracted the disease and died, probably because the pathogen got in through the pumping systems," Bronstein said.
Within two days of contracting the parasite, a healthy sea urchin becomes a skeleton with massive tissue loss. While some corpses are washed ashore, most sea urchins are devoured while they are dying and unable to defend themselves, which could speed up contagion spread by the fish who prey on them.
"As with COVID-19, at this point, no one knows what will happen--will this epidemic disappear by itself, or will it stay with us for many years and cause a dramatic change in coral reefs?" Bronstein said.
An urgent report describing the situation was submitted to the Israel Nature and Parks Authority, and emergency steps for saving the coral reef are being considered. —ANI
