We studied the movements of burbot Lota lota from October 1983 to December 1984 in the upper reaches of the Tanana River, a glacial tributary of the Yukon River in eastern Alaska. We surgically implanted radio transmitters into 21 burbot and monitored the fish by aerial telemetry once every 3 weeks. Fish were relocated up to 68 km downstream and 84 km upstream from release sites. The longest combined upstream and downstream movement observed for an individual fish was 125 km. Burbot were usually relocated in the main river channel, even during summer when peak flows caused high turbidity and channel scouring. Although burbot moved about during all seasons, their longest movements occurred during November–March, the normal period of spawning activity.

During 1984 and 1985, 67 adult Arctic grayling Thymallus arcticus with surgically implanted radio transmitters were released at their summer feeding areas in three river systems of the Arctic National Wildlife Refuge, Alaska. We tracked the fish from aircraft to determine patterns of autumn migration to overwintering locations. During August or September in each area, fish left the small tundra streams where they were tagged and migrated into larger streams. Migration rates peaked at 5–6 km/d about 1 September and averaged 1 km/d. Fish in two river systems moved into adjacent rivers after passage through estuarine waters. Migration distances from spawning or summer feeding areas to overwintering sites were as great as 101 km. Potential overwintering areas determined from transmitter relocations included deep pools, spring‐fed areas, and lakes. Management problems associated with these extensive seasonal migrations may include the maintenance of the species migratory circuit in a region that may face future development.

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