Diadema antillarum, also known as the long-spined sea urchin, is one of the most important grazers on tropical coral reefs, removing algae and maintaining open space for coral growth.
In February 2022, we received reports of extensive Diadema die-offs in the Caribbean. While we do not know what is causing these die-offs, the speed at which large numbers of sick urchins are now dying resembles the mass mortality event of four decades ago, in the 1980s.
You can help track sea urchin health by adding your observations of healthy, sick, or dead urchins from dives at Flower Garden Banks National Marine Sanctuary, or anywhere in the Caribbean. These reports will allow scientists to determine the extent of the die-offs and share the sequence of events as they are happening.