Legendary Species · Montana
Rainbow trout in Montana
Oncorhynchus mykiss[1]
16 Montana waters whose agency species list names rainbow trout. Each links to its water page (gauge, regulations, access map, guides and shops) and to the agency list it comes from.
- 16waters list it
- 4destination hubs

Montana waters
Most fished first. A species missing from an agency list does not mean it is absent; this page lists only waters whose list names it (at least 5 are needed for a page).
- Madison RiverAgency list: Montana Fish, Wildlife & Parks
- Yellowstone RiverAgency list: Montana Fish, Wildlife & Parks
- Blackfoot RiverAgency list: Montana Fish, Wildlife & Parks
- Clark Fork RiverAgency list: Montana Fish, Wildlife & Parks
- Bitterroot RiverAgency list: Montana Fish, Wildlife & Parks
- Rock CreekAgency list: Montana Fish, Wildlife & Parks
- Beaverhead RiverAgency list: Montana Fish, Wildlife & Parks
- Jefferson RiverAgency list: Montana Fish, Wildlife & Parks
- Big Hole RiverAgency list: Montana Fish, Wildlife & Parks
- Smith RiverAgency list: Montana Fish, Wildlife & Parks
- Ruby RiverAgency list: Montana Fish, Wildlife & Parks
- Gallatin RiverAgency list: Montana Fish, Wildlife & Parks
- Boulder RiverAgency list: Montana Fish, Wildlife & Parks
- Bighorn LakeAgency list: National Park Service (Bighorn Canyon National Recreation Area)
- Ennis LakeAgency list: Montana Fish, Wildlife & Parks
- DePuy Spring CreekAgency list: Montana Fish, Wildlife & Parks
Identification
- Rainbow trout vary a lot in colour and shape. Adults are silver with many small black spots, a pink or red band along the side, and spots that often run in lines along the tail rays.[2]
What the source says
“Highly variable in color and body shape, especially between resident fish and steelhead. Adults are silver and heavily spotted with small black spots. Iridescent pink or red along the lateral band. Numerous black spots pepper the body and dorsal fin, often radiating in lines along the rays of the tail.”
- The cheeks are pink and the back ranges from iridescent blue to nearly brown, with silver, white or yellow sides and belly. Young fish carry large, dark oval parr marks along the lateral line.[2]
What the source says
“Opercula (cheeks) are pink, the back iridescent blue to nearly brown, and the sides and belly silver, white or yellow. Juveniles have oval parr marks along the lateral line that are large and dark.”
- Rainbow trout and steelhead are the same species. Rainbows stay inland, while steelhead are the form that migrates to the ocean or, in Michigan, the Great Lakes.[1]
What the source says
“Genetically rainbow trout and steelhead are the same species but lead very different lives. Rainbow trout stays inland, and an anadromous form that migrates to the Great Lakes (or ocean in their native habitat).”
Status, protections and rules
As each agency stated them on the date read; a rule applies only where its agency says so. Check the current regulations for the water before you fish.
- In Great Smoky Mountains National Park, rainbow trout are non-native. The National Park Service says rainbow trout introduced in the early 1900s, together with logging, cost native brook trout 75% of their habitat.[3]
What the source says
“In the early 1900s, significant environmental changes occurred in the park due to logging and the introduction of non-native rainbow trout, which destroyed 75% of the native brook trout's habitat. Rainbow trout out-competed brook trout by reproducing at a faster rate as well as growing faster, taking over the streams.”
- Yellowstone National Park rule: in the Lamar River drainage, including parts of Slough and Soda Butte creeks, every rainbow trout caught must be killed. Releasing one alive is illegal there.[4]
What the source says
“All rainbow trout, brook trout, and identifiable cutthroat/rainbow hybrids caught in the Lamar River drainage, including portions of Slough and Soda Butte creeks, must be killed—it is illegal to release them alive.”
Water temperature in Montana
- Under Montana FWP's 68°F lineMontana FWP cites a study in which trout “caught and released from water with a temperature above 68 degrees F were far more likely to perish than those taken from cooler water.” Water warms through the day: “Fish in the cool morning hours.”
- Warm for released troutAbove 68°F, released trout were “far more likely to perish than those taken from cooler water” (the study Montana FWP cites). FWP: “Fish in the cool morning hours — low water flow and rising temperatures combine to stress fish.”
- 66°F: Montana's cutthroat triggerMontana rule, cutthroat trout waters only: “In cutthroat trout waters, angling restrictions occur when the temperatures reach at least 66 degrees for three consecutive days.”
- 73°F: Montana's hoot-owl triggerMontana rule: FWP's drought policy provides for angling restrictions “when maximum daily water temperatures reach at least 73 degrees for three consecutive days”; hoot-owl restrictions “prohibit fishing from 2 p.m. to midnight each day.” FWP sets them reach by reach: check the current list.
- 77°FMontana FWP: “Water temperatures of 77 degrees or more can be lethal to trout.”
Sources: “Giving a hoot”, Montana Outdoors (July–August 2024) (Montana Fish, Wildlife & Parks); Drought and fishing (Montana Fish, Wildlife & Parks); Additional fishing restrictions begin July 22 on several Montana rivers (21 July 2026) (Montana Fish, Wildlife & Parks); Current waterbody restrictions (Montana Fish, Wildlife & Parks).
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.
- Bozeman & Livingston, Montana6 rainbow trout waters
- Ennis & the Madison Valley, Montana6 rainbow trout waters
- Missoula, Montana4 rainbow trout waters
- Island Park & the Henry's Fork, Idaho1 rainbow trout water
Hatch & season charts
- Northern Rockies8 sourced rows
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.
- Rainbow trout Michigan Department of Natural Resources, read Oct 24, 2026.
- Fishing for Coastal Rainbow Trout / Steelhead California Department of Fish and Wildlife, read Oct 24, 2026.
- Fish - Great Smoky Mountains National Park (U.S. National Park Service) National Park Service, read Oct 24, 2026.
- Fishing - Yellowstone National Park (U.S. National Park Service) National Park Service, read Oct 24, 2026.
