European Conger

Photo: Kevin Bryant · CC BY-NC-SA

The sea caves of Procida's northern coast shelter conger eels reaching well over a metre in length, which rest motionless in cave entrances during daylight hours before moving into open water to hunt after dark. Unlike the Mediterranean moray they tend toward a single large den rather than crevices, and the same cave entrance can be visited repeatedly to find the same individual. Night dives here reveal conger actively coursing the reef surface, a dramatically different behaviour from their catatonic daytime posture.