A nocturnal inshore movement of juvenile cod Gadus morhua L. in eastern Newfoundland

Juvenile cod Gadus morhua L. (aged 1 + and 2 +) were counted, using an underwater scuba transect method, during the day and at night in shallow water at Newman Sound, Bonavista Bay, Newfoundland. They were 16 times more abundant during the night than during the day. Sampling at one site throughout a 24-h period showed that they arrive in shallow water at dusk, and leave again just before dawn. Much searching among algae and in crevices showed that the young cod are not simply hiding in cryptic habitats during the day. The hypothesis that they spend the day in deeper water is presented.