Scientists Link 95% Black Sea Urchin Die-Off to Philaster Parasite
Updated
Updated · Oceanographic Magazine · Aug 6
Scientists Link 95% Black Sea Urchin Die-Off to Philaster Parasite
1 articles · Updated · Oceanographic Magazine · Aug 6
Summary
Philaster apodigitiformis was identified as the pathogen behind the 2022-23 mass mortality of long-spined black sea urchins across Florida and the Caribbean, where more than 95% of populations died within weeks.
Scientists found the ciliate in every sick urchin and none of the healthy ones, then reproduced the disease by exposing healthy animals to the parasite, triggering spine loss, disintegration and death.
The collapse matters because Diadema antillarum is a key algae grazer; without it, algae can overrun reefs, block light and space, and worsen coral bleaching.
The report links the new finding to the region-wide 1983 urchin crash and coral decline, though it says the earlier event cannot be confirmed because biomolecular testing was unavailable then.
Researchers in the United States and elsewhere are now working on ways to manage the outbreak risk and protect reef recovery in Florida and the wider Caribbean.