Sea urchins are dying in large numbers across the Caribbean, according to scientists who are racing to pinpoint the cause of the mysterious die-off.
The rapid and widespread deaths of long-spined sea urchins (Diadema antillarum) were first observed in February in the U.S. Virgin Islands but have since spread as far west as Jamaica, according to the Atlantic and Gulf Rapid Reef Assessment, an organization that monitors the health of coral reefs in the western Atlantic Ocean and Gulf of Mexico.
Such a severe die-off of sea urchins has not been seen in the Caribbean since the 1980s, according to the research group. Scientists warn that the loss of urchins — which help maintain a healthy environment for corals to grow — could be devastating for the broader marine ecosystem.
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"The 1980s die-off event is recognized as one of the main contributors to the decline of coral reefs throughout the region that we've observed since that time," said Joshua Patterson, an associate professor of fisheries and aquatic sciences at the University of Florida.
It's not yet known why the urchins are suffering — or how to stop the situation from deteriorating.
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