Owyhee River Hatch Chart | The Fly Fishing Place

Southeast Oregon. The Owyhee tailwater below Owyhee Reservoir is one of the most technical and rewarding trout fisheries in the Pacific Northwest - a remote, canyon-cut desert river holding large, educated rainbow trout in clear, slow-moving water. The tailwater effect keeps temperatures stable year-round, producing consistent midge and BWO hatches even in the coldest months.

The primary public access section runs through the Leslie Gulch / Owyhee Canyon area. This is catch-and-release, artificial lures only water - confirm the exact boundaries with current ODFW regulations before you go. Roads into the canyon are unpaved and can be impassable when wet. Check conditions before making the drive.

The Owyhee demands small flies, long leaders, fine tippet, and precise presentations. Fish are large and selective. This is not a river that rewards sloppy casting or heavy tackle.

Shop by type: dry flies, nymphs, Euro nymphs, hoppers and terrestrials, streamers.

Year at a glance

Month	Primary hatches	Also carry	Typical sizes
Jan	Midges	BWO on mild days	20-24 midge, 20-22 BWO
Feb	Midges, BWO	Small stonefly nymphs	18-24
Mar	Midges, BWO	Early caddis on warm afternoons	18-22 midge, 18-20 BWO
Apr	BWO, midges, caddis	March Brown, early PMD	16-22
May	Caddis, PMD, BWO	Pale evening dun	PMD 16-18, caddis 14-16
Jun	PMD, caddis, pale evening dun	Yellow sally, BWO	PMD 16-18, PED 16-18
Jul	Caddis, PMD, pale evening dun	Hoppers, tricos start	14-18
Aug	Tricos, hoppers, caddis	Ants, beetles, late PMD	Trico 20-24, hopper 8-12
Sep	BWO, tricos, caddis	Hoppers, mahogany dun	18-22 BWO, trico 20-24
Oct	BWO, midges, mahogany dun	October caddis, streamers	18-22
Nov	Midges, BWO	Small nymphs	20-24
Dec	Midges	BWO on mild days	20-24

January

The Owyhee's tailwater character keeps it fishable year-round. January midge fishing can be outstanding on calm, sunny afternoons when fish stack up in the slow pools and flat tailouts. Go small, go fine, and move slowly.

Midges - 20-24. A zebra midge in size 20-22 is a starting point - go smaller when fish are sipping. Two-fly midge rig under an indicator or tight-line through slow tailouts.
BWO - 20-22 on overcast afternoons. A sparse BWO dry when fish are visibly rising.

February

Midge and BWO program continues. Olives increase on gray afternoons. The canyon walls trap warmth and midday can be surprisingly comfortable. One of the less-pressured months on this fishery.

Midges and BWO on overcast days.
Pheasant tail nymphs sized down to 18-20 for Baetis subsurface.
Small dark stonefly nymphs along the bottom.

March

BWO hatches strengthen. Midge activity remains consistent. Early caddis begin appearing on warmer afternoons by late month. March is an excellent time to fish the Owyhee before spring crowds arrive and before road conditions become an issue with late rain.

Midges - 20-24. Larvae and pupae subsurface, adults when fish are rising.
BWO - 18-22. BWO dry and Barr's Baetis emerger.
Late March: early tan caddis on warm afternoons.

April

Spring arrives in the canyon. Caddis become more reliable. BWO continue on cloudy days. PMDs may begin showing by late April. This is prime time on the Owyhee - stable flows, active fish, and a full menu of hatches developing.

Caddis - 14-18. Elk hair caddis and the caddis assortment.
BWO and midges on overcast days.
Early March Brown - 14-16.

May

Peak spring fishing. PMDs and caddis overlap with continued BWO activity. The tailwater keeps flows stable when other Oregon rivers are blowing out with snowmelt - a significant advantage for planning a May trip. Pale evening duns add a third dry-fly option in the evenings.

PMD - 16-18. Pale Morning Dun mornings. A pheasant tail dropper underneath covers the nymph stage.
Caddis - 14-16 afternoons and evenings. Elk hair.
BWO on overcast mornings.
Pale evening dun - 16-18 at dusk.

June

Excellent fishing across the canyon. PMDs and caddis dominate. Pale evening duns can produce exceptional dry-fly rises at last light. Yellow sallies in the faster riffles. The desert canyon heats up by midday - fish early morning and evening for the best action.

PMD - 16-18. Pale Morning Dun with a pheasant tail dropper.
Pale evening dun - 16-18 at dusk. Fish are often most active in the last hour of light.
Yellow sally - 14-16 in riffled sections.
Evening caddis. Elk hair.

July

Midsummer heat moves fish to early and late feeding windows. Tricos begin on the slower flat sections. Hoppers appear along the sparse desert grass and shrub edges. Fish the canyon in the first two hours of light and again in the evening - midday can be very slow.

PMD mornings - Pale Morning Dun.
Trico - 20-24. Early morning spinner falls on flat, slow water. Fine tippet essential.
Early hoppers along desert edges - hoppers and terrestrials.
Evening caddis and pale evening dun. Elk hair.

August

Trico spinner falls are the signature hatch of high summer on the Owyhee - technical, demanding, and uniquely rewarding. Large fish rise in the flat pools to size 22-24 flies on 7X tippet. Hoppers work the banks and riffles. Fish early and be off the exposed canyon rim by early afternoon during thunderstorm season.

Trico - 20-24. The most important August hatch. Morning spinner falls bring large fish to the surface. Spent-wing patterns on 6X or 7X tippet.
Hoppers - 8-12. Desert shrub and grass edges. Shop hoppers and terrestrials.
Ants and beetles in foam lines.
Late PMD on cool mornings.
Evening caddis.

September

Outstanding month. BWO return strongly as nights cool. Tricos continue into mid-September. Hoppers hold through mid-month. One of the least-crowded months with some of the best dry-fly conditions of the year. The desert light and canyon scenery in September are exceptional.

BWO - 18-22. Parachute BWO and Baetis emerger.
Tricos through mid-September on flat water.
Hoppers and ants through mid-month.
Mahogany dun - 14-16 on overcast afternoons.
Streamers in deeper slots at last light.

October

Fall BWO fishing is among the best of the year - dense hatches on gray afternoons, selective fish, and virtually no other anglers. Mahogany duns add a second dry-fly option. October caddis appear on warmer afternoons. A phenomenal month for anyone willing to make the drive into the canyon.

BWO - 18-22. The dominant hatch. Sparse patterns, fine tippet, accurate presentation.
Mahogany dun - 14-16 on overcast afternoons.
October caddis - 8-12 on warm afternoons.
Midges - 20-24 in slow tailouts.
Streamers in deeper runs at last light.

November

Back to the midge and olive program. The canyon is nearly empty. Cold mornings and short days, but calm, mild afternoons can produce exceptional dry-fly fishing to midging fish in the flat pools.

Midges - 20-24. Two-fly rig through slow water.
BWO on overcast afternoons, 18-22.
Small nymphs sized down to 18-20.

December

Midge season. Road access can be limited by wet weather or early snow - check conditions before making the trip. When accessible, the Owyhee in December can surprise with willing fish in the flat pools on calm, mild afternoons.

Zebra midge and small nymphs - 20-24.
BWO on mild, overcast afternoons.

An Owyhee box starts with a deep midge selection in sizes 18-24 and a strong BWO assortment. Add PMDs, trico patterns, pale evening duns, caddis, and hoppers for the summer season. Go one size smaller than you think you need - this river rewards anglers who err on the side of smaller and finer. Start with the western dry and nymph assortment and supplement with smaller sizes.