Grayling · Thymallus arcticus
Arctic Grayling
Also called Grayling, Sailfish of the north.
Short answer
The Arctic grayling is a salmonid with an enormous sail-like dorsal fin, a small mouth and a silver-purple sheen. In the lower 48 it survives natively only in Montana's Big Hole and a few connected waters; in Alaska it is abundant and rises freely to dry flies all summer.
How to identify a arctic grayling
- Dorsal fin
- Huge, sail-like, spotted and iridescent. Nothing else in fresh water has one.
- Colour
- Silver-grey flanks with a purple or lilac sheen, and a scattering of dark spots on the shoulder.
- Mouth
- Small and delicate relative to the body, which is why hooks pull free so easily.
- Adipose fin
- Present, confirming it is a salmonid.
What a arctic grayling is
Grayling are salmonids but not trout, and the enormous dorsal fin makes them unmistakable — a sail of purple and orange spotted membrane that a hooked fish uses to hold itself in the current. They were once native to Michigan and to Montana's upper Missouri; the Michigan population was extinct by the 1930s after logging and overfishing, and the Montana fluvial population in the Big Hole is now one of the last river-dwelling grayling populations in the lower 48. In Alaska and northern Canada they remain abundant, and they are among the most willing dry-fly fish anywhere.
- Native to
- Native to Alaska, northern Canada, and historically to Montana's upper Missouri drainage and Michigan.
- Typical size
- Ten to fourteen inches commonly. Alaskan fish reach eighteen to twenty inches and are considered large.
- What they eat
- Drifting insects, taken in the surface film more readily than almost any other salmonid. Grayling hold in open current and intercept whatever comes down.
Where arctic grayling live
Abundant throughout Alaska and northern Canada. In the lower 48, natively only in Montana's Big Hole and Red Rock drainages, with introduced populations in high lakes in Montana, Wyoming, Utah and Colorado.
Fly fishing in Alaska Fly fishing in Montana Fly fishing in Wyoming Fly fishing in Utah
Conservation status
Secure in Alaska. The Big Hole fluvial population is a long-running conservation concern and the subject of a major restoration effort; the Michigan population is extinct. Special regulations apply in Montana.
Protected status and the rules that follow from it are set state by state and change. Before you fish, check the current regulations for the water you are standing in — this page is a starting point, not a legal reference.
How to catch arctic grayling
Fish a small dry fly in open current and expect takes. Grayling are not selective and will rise repeatedly, which makes them one of the best fish for a beginner or a child. The difficulty is the mouth — it is small and soft, hooks pull out easily, and a gentle hand on a light tippet lands more fish than a firm one. In Alaska they often sit behind spawning salmon alongside the rainbows.
- The sail-like dorsal fin is the whole identification. Nothing else has it.
- The mouth is soft. Play them gently or you will pull the hook.
- In the lower 48 the native river population is Montana's Big Hole, and it is fragile.
Flies that work for arctic grayling
Each of these is a card in the deck, and each has a full page in Our Fly-brary.
Keep reading
- How to release a trout — handling, and why it matters more for some species than others
- How to read water — where each of these fish holds
- Hatches and what trout eat — the food these fish are feeding on
- Fly fishing by state — which species you will meet, state by state
Rainbow Trout Brown Trout Brook Trout Cutthroat Trout Steelhead Bull Trout Lake Trout Golden Trout Dolly Varden Tiger Trout Mountain Whitefish