The diel movements of seven adult burbotLota lota, 55–67 cm in total length, were seasonally monitored with sonic tags in Lake Opeongo during 1989 and 1991 to determine patterns of activity and habitat use. Burbot were inactive during daylight hours, began moving near dusk, and moved throughout each night until dawn. In the summer, burbot moved more slowly and occupied deeper water than in the spring. Swimming speed appeared to increase in the fall. Burbot occupied the same local areas within seasons and between years. Burbot were sometimes active in 20°C water for extended periods at night but moved to cooler water during the day. Burbot seemed to use an area-restricted searching pattern. None of the burbot were located in water less than 2 m deep.