Comprehensive DescriptionRead full entry
BiologyOccurs in cold brackish and moderately saline water near the coast (Ref. 27547). Enters coastal rivers and may occur as far as 120 miles inland (Ref. 5723). Landlocked in lakes (Ref. 59043). Maximum depth reported at 100m (Ref. 35388). Benthic (Ref. 58426). Movements are limited to short onshore-offshore seasonal movements and mass movements of fry into shallow water in autumn (Ref. 28908, 28910). Moreover, there are no migrations of large numbers; movement into freshwater and long distances up rivers are apparently undertaken by relatively few individuals at a time (Ref. 27547). Diurnal from November to April but is largely nocturnal the rest of the year (Ref. 28905). Feeds on small crustaceans, fishes (Ref. 4968) and molluscs (Ref. 58426). Spawning takes place in shallow waters, male digs a groove in the gravel where pairing and egg laying occur. Move to deeper water in the spring, where they stay in summer (Ref. 35388). Landlocked populations are locally threatened (Ref. 59043).