Grayling are easily distinguished from other game fish: they have an immense dorsal fin with twice the number of supporting rays, an under slung mouth with few apparent teeth, and a sharply forked tail. Taken together these features make grayling unmistakeable. The Grayling is a spring spawning species (unlike trout which spawn in late autumn and early winter) Grayling are also prepared to feed in lower water temperatures when other game fish are lethargic.