Brown trout are a European fish, Salmo trutta, brought to the United States in the 1880s from German and Scottish stock and spread West on the same railroads that carried rainbows East. They are the only trout on this site that is not native to North America, and they are now the dominant fish on a large share of the West's best rivers: the Middle Provo, the Weber, the Taylor, the East Walker, the Arkansas, the lower Yellowstone. Sixty-five of the ninety-two river pages here list them. GBIF records place brown trout in Wyoming, New Mexico, Colorado, Utah, California, Idaho, Montana, Arizona, Oregon and Nevada among the Western states, along with a long list of Eastern and Midwestern ones.
Why browns are harder to catch than rainbows
The wariness of brown trout is not folklore. They are a fall-spawning fish that evolved in clear, heavily fished European rivers, and the traits that survived are the ones that avoid predators: a preference for cover, a habit of feeding hardest in low light, and a tendency to inspect a fly rather than lunge at it. Where a rainbow in a riffle has a fraction of a second to decide, a brown in a slow pool has all the time it wants. The river pages here say it in different ways for different rivers. The browns of the Blue River Gold Medal section are described as highly selective and educated by constant pressure. The Hat Creek browns are called among the most technically demanding wild browns in California, fished on 6x and CDC emergers rather than standard dries. The Silver Creek browns are extremely cautious, holding in the slower, deeper sections where they can watch a fly for a long time before refusing it.
Where browns hold, and where rainbows do not
If you fish a river that has both species, the split is consistent enough to plan around. Browns take the slow, deep, shaded water: undercut banks, the inside of bends, the tail-out of a pool where the current slackens, logjams and root wads, and the soft water tight against a cutbank. Rainbows take the current. On the Middle Provo, the large browns hold along undercut sod banks and the advice on that page is to cast within inches of the grass. On the Logan the browns are concentrated in the deeper pools while the rainbows spread through the canyon. On the San Juan and Lees Ferry, both rainbow-dominated tailwaters, the fewer browns that do exist are found in the slower eddy water rather than the main flow. On the Green below Flaming Gorge, browns become the majority of the catch as you move downstream from the A section into the slower, warmer B and C sections.
Browns are also more tolerant of warm water than rainbows and far more tolerant than cutthroat or brook trout, which is why they dominate the lower, warmer reaches of many rivers: the Cache Valley sections of the Bear, the lower Owens, the valley reaches of the Gallatin below the canyon, and the lower Pecos near the village.
How browns feed through the year
Browns eat insects like any trout, but they take a larger share of their diet as bigger prey as they grow: sculpins, crayfish, smaller trout, mice on the right night. Through the hatch season they are still surface fish on the right water. On the Weber and the Middle Provo, the Mother's Day Caddis in late April and May is the event that brings the big browns up, and the fall Blue-Winged Olive hatches bring them up again in October. On the Arkansas and Taylor the Pale Morning Dun in summer is the dependable brown trout dry-fly window. On the East Walker, one of the finest wild brown populations in the Great Basin, the browns are most active during the Blue-Winged Olive hatches in spring and fall.
Between hatches, browns feed subsurface and in low light. Early morning and the last hour before dark are brown trout hours on every river listed here, and a nymph fished deep along a cutbank at midday will often find a brown that would never rise.
The fall spawn and what it means for the angler
Browns spawn in fall, typically October into November depending on elevation and latitude, and they move upstream and stage in the weeks before. This is the season most river pages here flag as prime: the Bighorn, Madison, Yellowstone, Big Hole, Frying Pan, Gunnison, Walker and Rock Creek pages all name fall as the brown trout window. Targeting these staging fish is a subject of its own, covered on the trophy brown trout guide. For general fishing, the practical points are simpler: avoid wading through clean gravel in tail-outs from October on, since that is where redds are, and leave actively spawning fish alone. Some states close specific reaches during the spawn. Check the agency for the river you are fishing.
Rivers on this site with strong brown trout fishing
- Provo River, Middle section, Utah: the dominant species, with the largest average size in the Provo system, on a meadow tailwater with undercut banks.
- Taylor River, Colorado: a Gold Medal tailwater where browns dominate and fish technical dries on 5x and 6x.
- East Walker River, Nevada: desert tailwater browns below Bridgeport Reservoir, less pressured on the Nevada side.
- Hat Creek, California: spring-creek browns in the Wild Trout section below Powerhouse No. 2.
- South Platte River, Colorado: browns dominate Cheesman Canyon and feed on fall Baetis and winter midges.
A practical approach for browns
Fish the bank, not the middle. Get the fly tight to cover, within a foot of an undercut or a log, and accept that you will lose flies doing it. Fish early and late. On a bright midday, go subsurface with a Pheasant Tail or a stonefly nymph in 12 to 16 and drift it along the deep edge of a pool. During a hatch, use a longer leader and finer tippet than you would for rainbows, and match the emerger stage rather than the dun, because browns often take the crippled or emerging insect just under the film. Woolly Buggers in 6 to 10 fished on a floating line along the banks will find browns in most freestones without any of the specialized gear the trophy page describes. And check the state agency for the water you are on before a fall trip, since spawning-season closures are the rule that changes most often.