Samenvatting

Diadema sea urchins (Diadema antillarum) are important algae grazers, but restoration attempts often record low survival of restocked individuals. This article sheds light on one of the causes for unsuccessful restocking. Restocked sea urchins were monitored with time-lapse cameras for 10 days. There were strong indications that queen triggerfish (Balistes vetula) waited till sunset, when Diadema sea urchins become active, to feed on their favourite prey. The abundance of this predator should therefore be a crucial factor to consider when aiming for restocking of Diadema sea urchins on Caribbean coral reefs.