Sea urchins in the Gulf of Aqaba are dying at an alarming rate, threatening the precious ecosystems of the Red Sea’s coral reefs.

The giant black sea urchin (Diadema setosum) is being killed by an unknown pathogen, according to Tel Aviv University scientists. Episodes of their mass death were first observed in the eastern Mediterranean in early July last year and gradually spread. In January last year, they were recorded in the north of the Gulf of Eilat (or Aqaba), and now, according to researchers, they have spread south to the Red Sea.

This sea urchin plays a key role in maintaining the health of coral ecosystems. Without it, algae grow uncontrollably, suffocating corals and upsetting the delicate balance of the reef ecosystem.

“This is a quick and violent death: in just two days, a healthy sea urchin turns into a skeleton after massive tissue loss,” he explains. Omri Bronsteinmarine biologist at Tel Aviv University and lead author of a series of studies on the subject.

As for the causes of the mass deaths, Omri notes that the possibility of local poisoning or contamination has been ruled out, and scientists likely attribute the phenomenon to a “rapidly spreading epidemic” caused by an as-yet unknown pathogen.

Last month, US researchers identified a single-celled parasite responsible for a similar mass extinction of sea urchins in the Caribbean, while their Israeli colleagues suggested that a similar pathogen could be responsible for the phenomenon in the Mediterranean and Red Seas.

“It would be interesting to know if the parasite from the Mediterranean is the same parasite as the Caribbean one. If so, then questions arise about how it moved between such geographically isolated areas, ”said Ian Hewson, a professor at Cornell University who was not involved in the study.

The Gulf of Eilat, a section of the Red Sea shared by Egypt, Israel, Jordan and Saudi Arabia, is home to remarkable coral reefs that scientists say may be more resilient to warming waters due to anthropogenic climate change.

Source: Associated Press.