The number and nature of muskellunge moving to and from spawning grounds are extensively documented. Individual spawning muskellunge in Stony Lake, Ontario are considered to home annually to specific spawning grounds and to specific areas (spawning sites) within spawning grounds. Some individuals were caught in the same location, or a nearby location, in as many as 7 yr. There is some evidence for discrete populations with apparent reproductive isolation and no interchange in summer. Dispersal from spawning grounds to summer home ranges seems to be limited in regard to direction and area sf the lake. Recapture of fish on spawning grounds suggests an obligatory return to a limited number of “traditional” spawning grounds and may extend our knowledge of the groups of fishes exhibiting this type of directed movement. The results also have serious implications for muskellunge in regard to management, shoreline development, and genetic contamination by fish culture activities.