Gunnison River Colorado Hatch Chart
Western Colorado, flowing northwest from its headwaters near Gunnison through the Black Canyon of the Gunnison and the Gunnison Gorge before joining the Colorado River at Grand Junction. The Gunnison River is Colorado's most dramatic trout fishery - a remote canyon river with exceptional populations of trophy brown and rainbow trout in two distinct Gold Medal sections that together represent some of the finest wild trout fishing in the American West. The Black Canyon section within Gunnison Gorge National Recreation Area and the upper river near Gunnison and Almont offer completely different experiences that together define the range of what the Gunnison system offers the dedicated fly angler.
Check current Colorado Parks and Wildlife regulations before you go. The Gunnison Gorge Gold Medal section has special regulations including artificial flies and lures only with catch-and-release required - one of Colorado's most protective wild trout designations. Access to the Gunnison Gorge requires a hike down steep canyon trails - this is not roadside water and first-time visitors should research the access routes carefully. The upper river near Almont and Gunnison has more standard regulations with some catch-and-release sections. A Colorado fishing license is required.
Shop by type: dry flies, nymphs, Euro nymphs, hoppers and terrestrials, streamers.
The river
The upper Gunnison near Almont - where the Taylor and East rivers converge to form the Gunnison - is a broad, accessible freestone river with good populations of wild browns and rainbows and consistent public access along the river corridor through the Gunnison Valley. This is the most approachable section of the Gunnison system - manageable flows, roadside access, and the kind of varied freestone character that makes it productive across the full hatch calendar. The upper river is excellent preparation for the more demanding downstream sections and is a destination in its own right for anglers based in the Gunnison and Crested Butte area.
The Gunnison Gorge below the Black Canyon is the river's legendary section - a remote, cliff-walled canyon accessible only by trail where trophy browns and rainbows inhabit some of the most spectacular river scenery in Colorado. The gorge requires a commitment: the hike in is steep and the water is powerful and demanding to wade. The reward is wild trout fishing with minimal pressure, exceptional fish size, and the kind of remote canyon experience that is increasingly rare on Colorado's more accessible rivers. The canyon walls of the Black Canyon rise thousands of feet above the river and the setting is unlike anything else in Colorado fly fishing.
The Gunnison system's salmonfly hatch is one of the most significant in Colorado - the canyon sections produce exceptional salmonfly hatches in late May and early June that bring large fish to the surface in the kind of aggressive feeding that defines the western salmonfly experience. Combined with the summer hopper fishing in the upper valley sections and the fall BWO hatches in the canyon, the Gunnison offers a complete seasonal fly fishing experience from early spring through late fall.
Year at a glance
| Month | Primary hatches | Also carry | Typical sizes |
|---|---|---|---|
| Jan | Midges, BWO | Small nymphs, streamers | Midge 20-26, BWO 18-22 |
| Feb | Midges, BWO | Small nymphs, streamers | Midge 20-26, BWO 18-22 |
| Mar | BWO, midges, blue quill | Small nymphs, streamers | BWO 16-20, midge 20-24 |
| Apr | BWO, caddis, midges | Blue quill, small nymphs | BWO 16-20, caddis 14-16 |
| May | Salmonfly, caddis, BWO | Golden stone, PMD start | Salmonfly 4-8, caddis 14-16 |
| Jun | Caddis, PMD, golden stone | Yellow sally, ants | Caddis 14-16, PMD 16-18 |
| Jul | Caddis, hoppers, PMD | Ants, beetles, yellow sally | Hopper 6-12, caddis 14-16 |
| Aug | Hoppers, caddis, PMD | Ants, beetles, trico | Hopper 6-12, caddis 14-16 |
| Sep | BWO, caddis, hoppers | Mahogany dun, ants | BWO 16-20, hopper 8-12 |
| Oct | BWO, midges, caddis | Mahogany dun, streamers | BWO 16-20, midge 20-24 |
| Nov | BWO, midges | Small nymphs, streamers | BWO 18-20, midge 20-26 |
| Dec | Midges, BWO | Small nymphs, streamers | Midge 20-26, BWO 18-22 |
January - February
The upper Gunnison near Almont fishes through winter with midge and BWO activity on the warmer afternoons. The Gunnison Gorge is accessible in winter but the hike in and the powerful canyon flows make it a demanding destination in cold conditions - the upper river is the more practical winter option for most anglers. Streamers for large browns in the deeper canyon pools and undercut banks. The Gunnison Valley in winter with the West Elk Mountains above and midging fish in the upper river is a quiet and productive off-season option for the Gunnison area angler.
- Midges - 20-26. Upper river on warmer afternoons. Subsurface and surface on midge clusters when fish are dimpling.
- BWO - 18-22 on overcast afternoons. Parachute and CDC emerger styles.
- Streamers for large browns in the deeper pools and undercut banks.
- Small nymphs subsurface throughout.
March - April
BWO hatches strengthen through March on the upper river and begin appearing in the Gunnison Gorge on the warmer afternoons. Blue quill on the upper river sections. Caddis begin building in April - early caddis activity in the canyon is the first signal of the approaching prime season. The pre-runoff April window is excellent across all sections - fish in prime spring condition, good hatches, and the gorge accessible before the high water of May. Monitor flows carefully as snowmelt begins in late April.
- BWO - 16-20 on overcast afternoons. The dominant spring hatch on the upper river and canyon sections.
- Blue quill - 16-18 on the warmer upper river afternoons.
- Midges throughout - 20-24.
- April: caddis building - 14-16 in the canyon sections.
- Small stonefly nymphs subsurface through April.
May - June
The salmonfly hatch in the Gunnison Gorge in late May and early June is one of Colorado's great dry-fly events - the remote canyon with minimal pressure and large browns feeding aggressively on salmonfly adults creates the kind of fishing that anglers plan trips around years in advance. Timing the hatch requires attention to water temperature in the canyon - call Gunnison area fly shops for current conditions before committing to the gorge hike. Post-runoff June brings caddis, golden stones, and PMDs as the canyon transitions to its summer character. The upper river near Almont is a productive alternative during runoff when the gorge is blown out.
- Salmonfly - 4-8 in the Gunnison Gorge late May through early June. The signature Gunnison hatch. Large foam and deer hair patterns. Hike to the canyon - the gorge has the best fish and the best hatch.
- Golden stone - 6-10 following the salmonfly through June.
- Caddis - 14-16 evenings throughout. Building strongly through May and June.
- PMD - 16-18 mornings building through June on the canyon and upper river sections.
- BWO on overcast days through May.
July - August
Summer hopper and caddis fishing across all sections of the Gunnison. The upper river near Almont and Gunnison has outstanding hopper fishing along the broad valley margins - one of the finest hopper stretches on any Colorado river with the Elk Mountains and West Elks as backdrop. The Gunnison Gorge in summer rewards the angler willing to make the hike with large browns on hoppers and caddis with virtually no competition. Caddis evenings throughout. PMDs continue through July mornings. Ants and beetles midday. The summer Gunnison with morning hoppers and evening caddis is classic Colorado valley fly fishing at its best.
- Hoppers - 6-12 along the valley margins and canyon edges mid-July through August. Outstanding on the upper river near Almont.
- Caddis - 14-16 evenings. The most consistent summer hatch throughout all sections.
- PMD - 16-18 mornings through July.
- Ants and beetles midday - 16-18.
- Yellow sally - 14-16 in the faster riffle sections.
September - October
Fall is the finest season in the Gunnison Gorge. BWO return strongly with the cooling temperatures - the canyon produces excellent afternoon olive hatches through September and October with the dramatic canyon walls as backdrop and virtually no other anglers making the hike in after Labor Day. Hoppers through mid-September. Mahogany duns on overcast days. Streamers for large pre-spawn browns in October. The Gunnison Gorge in October with golden aspens on the canyon rim, BWO hatches on the river, and large browns in the deep pools is one of Colorado's most remote and most rewarding fall fly fishing destinations.
- Hoppers through mid-September - 8-12 along the canyon and valley margins.
- BWO - 16-20 on overcast afternoons. The dominant fall hatch in the canyon. CDC emerger and parachute styles.
- Mahogany dun - 14-16 on overcast afternoons in September and October.
- Caddis evenings through September - 14-16.
- Streamers - October into November for large pre-spawn browns in the canyon pools.
November - December
BWO and midges through November on the upper river with streamer fishing for large browns in the canyon extending into mid-November for committed anglers willing to make the hike. The upper Gunnison near Almont is the practical winter option - accessible, productive, and fishable on most winter days with midge and BWO activity. The Gunnison Valley in November with snow on the West Elk peaks and rising fish in the upper river is a quiet end to the Colorado fly fishing season.
- Streamers through mid-November in the Gunnison Gorge for large pre-winter browns.
- BWO - 18-20 on overcast afternoons through November on the upper river.
- Midges - 20-26 throughout. Upper river year-round on warmer afternoons.
- Small nymphs subsurface in the deeper upper river holds.
A western dry and nymph assortment covers the core season - add salmonfly patterns in sizes 4-8 for the May and June gorge hatch and a strong hopper selection for the upper valley in July and August. The Gunnison River is Colorado's most remote and most dramatic trout fishery - the gorge demands commitment but rewards it with wild trout fishing in a canyon setting that rivals anything in the American West. One of Colorado's essential fly fishing rivers.