Arctic grayling

Identification

• The most striking features are the large, sail-like dorsal (back) fin and colourful body markings.[1]
  What the source says

  “Its most striking physical features are the large, sail-like dorsal (back) fin and colorful body markings.”

• The dorsal fin is usually fringed in red and dotted with large iridescent red, aqua or purple spots and markings.[1]
  What the source says

  “Their dorsal fins are typically fringed in red and dotted with large iridescent red, aqua, or purple spots and markings.”

• USFWS says it is the only grayling species found in North America.[2]
  What the source says

  “They are the only salmonoid with a distinguishing sail-like dorsal and the only grayling species found in North America.”

Habitat and range

• Grayling live in open water in clear, cold, medium to large rivers and lakes.[2]
  What the source says

  “These fish inhabit open water in clear, cold, medium to large rivers and lakes.”

• In Alaska, grayling have the largest natural range of any sport fish, occupying nearly the whole state.[1]
  What the source says

  “In Alaska, grayling have the largest natural range of any sport fish, occupying nearly the whole state.”

Life history

• Grayling spawn in spring, scattering their eggs over gravel in moving streams.[4]
  What the source says

  “They are spring spawners and broadcast their eggs over a gravel bottom in moving streams.”

• Drifting aquatic insects, especially black flies, mayflies, stoneflies and caddisflies, are their main food.[1]
  What the source says

  “drifting aquatic insects, especially black flies, mayflies, stone flies, and caddis flies are their primary food items.”

Status, protections and rules

Legal status and rules as the agency stated them on the date read. Rules change: check the current regulations for the water.

• In 2020 USFWS announced that Endangered Species Act protections for the Upper Missouri River distinct population segment of Arctic grayling are not warranted.[3]
  What the source says

  “protections for the Upper Missouri River distinct population segment (DPS) of the Arctic grayling are not warranted”

• The Montana Field Guide says the river-dwelling (fluvial) grayling population in the upper Big Hole River is the last remnant of Montana's fluvial grayling.[4]
  What the source says

  “Consequently, the fluvial or river-dwelling population in the upper Big Hole River are the last remnants”

• The Montana Field Guide gives Arctic grayling a state rank of S1.[4]
  What the source says

  “State Rank: S1”

• Historically, grayling also lived in Michigan, but USFWS says the Michigan population has been extirpated.[3]
  What the source says

  “While the Michigan population has been extirpated”

Fishing for it: what the agencies say

What agencies and extension services say about catching it, with the source for each line.

• ADF&G says general insect imitations such as the Adams dry fly and the hare's ear nymph usually work for grayling.[5]
  What the source says

  “Generalized insect imitations such as the dry fly "Adams" and the "hare's ear nymph" are usually effective patterns”

• In Yellowstone National Park, Arctic grayling, as native fish, must be released unharmed (NPS rule).[6]
  What the source says

  “All native fish must be released unharmed, including cutthroat trout, mountain whitefish, and Arctic grayling.”

Water temperature

Warm water stresses trout, char and salmon. These are the published temperature lines we show on every gauge, chosen state first: the state agency's own where it publishes one, otherwise federal guidance (said so). Each water page applies them to the gauge's live reading; the flow and temperature checker does the same for any gauge.

Where to fish for arctic grayling

Our 28 water pages whose agency species list names arctic grayling (each list links to the agency page it comes from). A species missing from a list does not mean it is absent: many agencies publish no list for a water.

Destination hubs

Hubs that list one of these waters, or that a water page is near: each has guides, shops, licences and trip planning for the area.

• Ennis & the Madison Valley, Montana6 arctic grayling waters
• Bozeman & Livingston, Montana2 arctic grayling waters
• Island Park & the Henry's Fork, Idaho2 arctic grayling waters

Keep exploring

• Arctic charSpecies
• Dolly VardenSpecies
• Northern Rockies hatch & season chart8 sourced rows
• Pacific Northwest hatch & season chart10 sourced rows
• California hatch & season chart19 sourced rows
• Southwest and Colorado hatch & season chart8 sourced rows
• All speciesIndex

Sources

Every fact on this page is our paraphrase of the page cited beside it, read on the date shown. Rules and seasons change: check the agency's current regulations before you fish.

1. Arctic Grayling Species Profile, Alaska Department of Fish and Game Alaska Department of Fish and Game, read Oct 24, 2026.
2. Arctic Grayling (Thymallus arcticus) | U.S. Fish & Wildlife Service U.S. Fish and Wildlife Service, read Oct 24, 2026.
3. Listing of the Arctic Grayling Not Warranted (press release, Jul 22, 2020; archived) U.S. Fish and Wildlife Service, read Oct 24, 2026.
4. Arctic Grayling - MONTANA FIELD GUIDE Montana Natural Heritage Program / Montana Fish, Wildlife & Parks, read Oct 24, 2026.
5. Arctic Grayling Uses, Alaska Department of Fish and Game Alaska Department of Fish and Game, read Oct 24, 2026.
6. Fishing - Yellowstone National Park (U.S. National Park Service) National Park Service, read Oct 24, 2026.