Trout Species of Utah

Utah's combination of cold tailwaters, productive freestone canyons, and isolated headwater basins supports more trout-species variety than most fly anglers expect. The Green River is regularly cited alongside the Bighorn, the Missouri, and the San Juan as one of the finest tailwater fisheries on the continent — wild browns and rainbows over selective midge and BWO water. Meanwhile the upper Bear, the Logan headwaters, and the Strawberry corridor still hold self-sustaining native cutthroat populations in their original ranges.

For a fly angler this means three things: the brown trout fishery is genuinely world-class, the native cutthroat are still here if you know where to look, and an honest week on Utah water can put five different species through your hands — including the one that shouldn't exist in the wild at all.

Non-native — dominant on the Green and Middle Provo

Brown trout are the headline species in Utah. The wild brown trout fishery on the Green River below Flaming Gorge is consistently ranked among the best in the lower 48 — fish over 20 inches are caught every season, and 24-inch wild browns are documented every year. The Middle Provo's wild brown population is dense enough that the river is regularly described in terms of fish-per-mile (the often-cited number is around 3,500). The Strawberry River's "Wild Strawberry" canyon section produces documented browns to 27 inches.

Stocked statewide, with significant wild populations

Rainbows are present in nearly every Utah trout water, through a combination of stocking and self-sustaining wild populations. The Middle Provo and the Strawberry River reservoir-influenced corridor are well-known for producing large rainbows; the Green River below Flaming Gorge holds wild rainbows alongside its more famous brown trout fishery.

Native — Bonneville Basin (Bear, Logan headwaters, Wasatch tributaries)

The Bonneville Cutthroat is Utah's official state fish — and one of two native cutthroat subspecies still hanging on in its original drainages. The species is endemic to the Bonneville Basin, the ancient lake bed that became the Great Salt Lake watershed. You'll find them in cold mountain streams of the Wasatch, the Bear River drainage above Cache Valley, and select Logan River headwater tributaries.

Native — Green River drainage, eastern Utah

The second native cutthroat subspecies in Utah. Colorado River Cutthroat are native to the Green River drainage — the upper Green and its tributaries on the Utah side of the Wyoming line, plus related drainages in eastern Utah. They share the basin with (and historically were displaced by) introduced rainbows and browns; some restored populations exist in protected headwater tributaries.

Non-native — high-elevation lakes and headwater streams

Brook trout are native to the eastern United States and were stocked across the Mountain West a century ago. In Utah they've taken firm hold in high-elevation lakes and small headwater streams — the Uinta Mountains, the high country of the Wasatch, and isolated drainages across the southern part of the state. They're beautiful, they're aggressive, and they're a problem where they overlap with native cutthroat.

Non-native hybrid — stocked by Utah DWR in select waters

The Tiger Trout is a hatchery-produced hybrid — a cross between a female brown trout and a male brook trout. Tigers are sterile (the chromosome counts of the parent species don't quite match up cleanly), which means they can't reproduce in the wild and DWR can stock them without risking new self-sustaining populations competing with natives. Utah DWR has run an active Tiger Trout stocking program in select reservoirs and rivers — the Fremont River is one notable place fly anglers regularly encounter them.

A note that doesn't fit cleanly into the species sections above: the Green River below Flaming Gorge deserves separate mention as one of the top tailwater fisheries in the American West, period. The combination of cold consistent flows out of Flaming Gorge, dense scud and midge populations, and decades of catch-and-release management on the upper sections has produced a wild brown trout fishery that regularly puts up 20-inch fish on technical dry-fly water. Section A from the dam to Little Hole is the wade-fishing crown jewel; the big fish are out there, the hatches are reliable, and the river fishes year-round thanks to the dam.

If you fish one Utah river in your life, fish the Green. Then come back the next year and fish the Middle Provo, because the contrast — Section A's selective trophy water versus the Middle Provo's dense wild populations — is what makes Utah's trout fishery so well-rounded.

Both Utah cutthroat subspecies — Bonneville and Colorado River — face the same set of pressures: hybridization with introduced rainbows (producing "cuttbows" that dilute native genetics), competition from brown trout in shared mainstem rivers, and direct displacement by brook trout in headwater streams. Utah DWR runs active restoration programs on key cutthroat streams — removing non-native trout from isolated reaches, re-introducing native broodstock, and installing barriers that prevent reinvasion.

Utah does not get the destination-trip attention that Montana, Wyoming, or Idaho get — and that's mostly to the benefit of anglers willing to look. The Green is a top-five Western tailwater. The Middle Provo holds 3,500 fish per mile. The Logan canyon fishes like the best small water in the Rockies. The native cutthroat are still in their original drainages. The state stocks a striped hybrid you can catch nowhere else. Show up with a fly rod and an open week, and Utah will hand you a more complete Mountain West trout experience than most anglers expect.