Mystery pathogen is stripping sea urchins of their flesh and turning them to skeletons -- and it's sp

[Judi Lynn]

Mystery pathogen is stripping sea urchins of their flesh and turning them to skeletons — and it's spreading fast

By Ben Turner published 30 May 2023

A mysterious epidemic that began in the Mediterranean at the start of the year looks set to wipe out all of the Mediterranean and Red Sea’s urchins, and possibly their coral reefs too.



Fish pecking at a dead sea urchin in the Gulf of Aqaba. (Image credit: Tel Aviv University)

A sudden and deadly epidemic sweeping across the Red Sea has killed an entire species of sea urchin, stripping their flesh and turning them into skeletons.

Just two months ago, thousands of black sea urchins (Diadema setosum) lived in the Gulf of Aqaba, in the northern tip of the Red Sea, keeping the corals there healthy by snacking on excess algae. Now, only their skeletons remain, after their tissue was consumed by a mysterious pathogen.

"It's a fast and violent death: within just two days a healthy sea urchin becomes a skeleton with massive tissue loss," Omri Bronstein, a senior lecturer in Zoology at Tel Aviv University, said in a statement. "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 by the fish who prey on them."

Researchers spotted the first signs of the urchin plague in the Mediterranean Sea at the beginning of the year, when an invasive species of urchin began falling sick in waters around Greece and Turkey. From there, the disease appears to have spread southward through the Suez Canal to the Red Sea.

More:
https://www.livescience.com/animals/mystery-pathogen-is-stripping-sea-urchins-of-their-flesh-and-turning-them-to-skeletons-and-its-spreading-fast