Habitat:
Mud and sand bottom from a few metres down to about 100 m, at sea and in estuaries, rarely entering freshwaters.

Biology:
Males reproduce for the first time at 2-3 years, females at 3-4. Spawns at sea, in January-June, in deep water, at temperatures around 6°C. Eggs and larvae are pelagic and drift with current. At about 10 mm SL, left eye moves to right side, pigmentation develops, and juveniles switch to benthic life. Juveniles enter freshwater to forage in mid-June in Kanin Peninsula, remaining there until August. Not all individual enter brackish and fresh-water. Adults do not move into brackish or fresh water. Feeds on thin-shelled molluscs and polychaetes.