Radio telemetry was used to determine overwintering, spawning, and summer feeding areas of adult Arctic grayling Thymallus arcticus in the Tok River drainage, a second order tributary of the upper Tanana River drainage of interior Alaska. In late September 1994, 25 adult Arctic grayling were implanted with radio transmitters. The fish were tracked from aircraft seven times from January to August 1995. By April, the fish had moved downstream 2 to 15 miles from the release site to four overwintering areas in the Little Tok and Tok rivers with the majority being found at the mouth of the Little Tok River. Spawning areas appeared to be restricted to the Station Creek drainage, a tributary of the Little Tok River. Distances traveled between overwintering areas and likely spawning areas ranged from 17 to 26 miles. After spawning, fish were dispersed along Station Creek and 28 miles of the lower Little Tok River. By August, fish had vacated Station Creek with the majority residing downstream in the Little Tok River.