RIVER FISH · Cold streams & cover

Brown trout

Salmo trutta

A nonnative trout in the United States that thrives in many cold streams, rivers and lakes and often uses undercut banks, pools and structure.

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Brown trout showing its spotted brown and golden sides
Photo: USFWS · Public domain ↗

Meet the fish

Habitat
Cold streams, rivers and lakes across a wide range of current speeds, with cover and suitable spawning gravel.
On the menu
Aquatic insects, crustaceans and fish; larger brown trout become increasingly predatory.
Size context
Size varies sharply with habitat: small-stream fish may stay modest while productive rivers and lakes can grow much larger trout.
Range & local context
Native to Europe, western Asia and parts of North Africa; introduced widely across the United States beginning in the late 1800s.

Living with the river

Water & habitat

Cold water, cover, flow stability and clean spawning gravel all matter. Temperature at one station cannot describe an entire trout reach.

Seasonal life

Brown trout generally spawn in fall, with females digging gravel redds where eggs develop through colder months.

Read the water, not a fishing score. Gauge readings describe one monitoring location. They do not prove fish are present, predict a bite, establish safe access or replace current fishing rules. Check the observation time and the specific stretch of river.

Before you go

Brown trout are nonnative in the United States and can affect native fishes in some waters. Local stocking, wild-trout and harvest rules vary.

Use the linked agencies and the relevant river guide for current regulations, closures and consumption advisories. A species profile is not a fishing license or a statement that harvest is allowed.

Editorial review: . Regional size examples are labeled; maximum lengths are not typical sizes.

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