The genus Diadema includes eight tropical and subtropical species, among them D. africanum, once common on rocky reefs off West Africa, the Azores, and the Canaries at depths of 16-66 feet.
In the islands, warming seas and predator overfishing helped fuel urchin booms from the 1960s onward, triggering recurring “urchin barrens.” Control efforts between 2005 and 2019 never fully solved the problem.
Then, in February 2022, everything flipped. A research team led by Iván Cano, a doctoral student at the University of La Laguna, began seeing mass die-offs of sea urchins near La Palma and La Gomera.
Over months, mortality spread eastward across the archipelago. Sick urchins moved sluggishly and erratically, stopped responding to touch, shed spines and tissue, and died.
They are returning, slowly. But it really wholloped the population.
That’s good to hear, I’m moving back eventually and can’t wait to kayak up the coast again