Fly Fishing Cayuse Creek, Idaho: Remote Cutthroat Water

Kelly Creek’s Long Tributary

Cayuse Creek runs into Kelly Creek, the big North Fork Clearwater tributary, in north-central Idaho. Fish and Game maps it at 35.9 miles across Clearwater and Idaho counties. That makes it longer than most of the “secret” Idaho waters on this site, and most of it is a long walk from any road.

The creek starts near 6,700 feet in the Bitterroot country east of the North Fork. It runs west from the headwaters, then hooks northeast for its last miles and meets Kelly Creek at about 3,270 feet. The mouth sits four trail miles above the end of the Kelly Creek road.

Fish and Game’s fisheries plan says much of the unaltered, roadless country in the Clearwater drainage lies in the upper North Fork near Kelly and Weitas creeks. Friends of the Clearwater puts a number on it: the Bighorn-Weitas Roadless Area, 260,000 acres in the Weitas Creek and Cayuse Creek drainages, is the largest roadless area entirely within the forest.

The Forest Service noticed the fishing too. In January 2025 its final forest plan study named Cayuse Creek one of 11 rivers suitable for Wild and Scenic designation, alongside Kelly Creek and its three forks. Its recreation study said that Kelly Creek, Cayuse Creek, the North Fork, the upper Lochsa, and Colt Killed Creek “stand out for trout fishing.”

For more small waters in this state, see our Idaho secret waters guide.

Regulations (Checked September 2026)

Cayuse Creek is not named in Idaho’s 2025 to 2027 rule book. Fish and Game’s Fishing Planner page applies the “Kelly Creek and tributaries” special rule to it, and the rule is short. Trout are catch-and-release, no bait is allowed, and barbless hooks are required.

The same rule covers Kelly Creek itself and every other Kelly Creek tributary. The rest of the North Fork drainage runs under different limits, so read the Clearwater Region pages before you fish the main river. The Clearwater Region office answers at (208) 799-5010.

The Fish: Wild Cutthroat Under a Quality Rule

Fish and Game’s planner page shows no survey and no stocking record for Cayuse Creek. What it has is a management direction. The 2025 to 2030 fisheries plan lists “Kelly Creek and its tributaries,” 60 miles, with cutthroat trout, rainbow trout, mountain whitefish, and bull trout, all native.

The cutthroat here are managed under the plan’s “Quality” category. The direction reads, “Manage Cutthroat Trout and Rainbow Trout to maintain a quality size structure and abundance.” Bull trout are to be kept stable or growing. That is a different job from the other North Fork tributaries, which are managed for harvest.

The state’s westslope cutthroat plan calls Kelly Creek a core conservation population. It says the North Fork, Kelly Creek, and the Little North Fork “all support healthy, viable cutthroat trout populations” with stable or increasing trends, and it schedules surveys every three to four years.

One survey detail is worth knowing. Kelly Creek snorkel counts in 2010 came in at about 60 percent of the 1989 count.

The biologists put that down to cool water rather than a decline, because in this system cutthroat move upstream as the water warms. In a hot August, that means the fish are higher up the creek than you expect.

Catch-and-Release Since 1970

Kelly Creek has been catch-and-release for more than 50 years. The state’s westslope cutthroat plan says anglers could keep 15 cutthroat a day here until 1970, when the limit went to zero. The North Fork went from 15 to 3 in 1972.

Friends of the Clearwater dates Cayuse Creek’s own catch-and-release rule to 1974. Today the rule book folds the creek into the Kelly Creek rule.

The results are in the state’s creel records. Angler effort dipped after the change, then climbed until the North Fork carried more than ten times the effort of the early 1970s, with higher catch rates.

Studies on Kelly Creek, the St. Joe, and the Lochsa in the 1960s and 1970s were among the first to document what catch-and-release does for cutthroat.

The other half of the story is the dam. The Army Corps of Engineers built Dworshak Dam on the North Fork between 1966 and 1973. At 717 feet it is the third-tallest dam in the country, and it has no fish ladder.

Fish and Game’s plan says the North Fork, “one of the most productive steelhead rivers in the state,” was eliminated from natural production of anadromous fish.

The North Fork “may have been the finest population of large-size steelhead in the world,” in a line quoted in the dam’s history. Its redband trout, the resident form of the same fish, fell by about 90 percent after the steelhead runs ended.

Flows and Summer Heat

No gauge has ever run on Cayuse Creek or Kelly Creek. The nearest live gauge is the North Fork Clearwater near Canyon Ranger Station, well downstream, with 60 years of record.

Source: USGS gauge 13340600, 1,296 square miles, monthly means 1967 to 2026.

Runoff peaks in May and is still high in June. Hoodoo Pass, the Montana way in, usually stays snowed in until early July, which lines up with the water. July’s average flow on the North Fork is about a third of June’s, and the small tributaries settle sooner.

The main river warms in summer. Average water temperature at the gauge is 64 degrees in July and 65 in August, then 57 in September. Cayuse Creek runs colder and higher, and the state’s own survey notes say cutthroat move upstream when the river warms. Follow them.

Getting There

Check the forest’s alerts page before you drive. As of mid-September 2026, two wildfire orders close Forest Road 250 from the Kelly Forks Work Center upriver to the Deception Saddle Road junction. Forest Order 01-17-53-26-004 runs through September 30, and the Moose Mountain Fire order, 01-17-53-26-008, repeats the closure through October 9.

That is the North Fork road on the Hoodoo Pass side. The Moose Mountain Fire order also closes an area of roads and trails north of the Kelly Creek road.

That order lists Forest Road 250 from Pierce to Kelly Forks and the Kelly Creek road, Forest Road 255, as open. Fire closures change fast, so call the North Fork Ranger District at (208) 476-4541 before you go.

How to Fish It

Everything about this creek says fish it lightly. A 4-weight, a floating line, and a box of attractor dries in sizes 12 to 16 will cover it from July into October. Pinch every barb, because the rule requires it, and leave the bait at home for the same reason. Our dry fly tips cover the presentation side.

Nothing gets kept. Every cutthroat, rainbow, and bull trout goes back, and the state manages this water for size and abundance, not harvest. Keep fish in the water, back the barbless hook out, and let them go where you caught them.

The walk shapes the day. Four miles of easy trail from the trailhead puts you at the mouth, where Kelly Creek is also catch-and-release. Most people fish the confluence and the first mile or two of Cayuse Creek. The trail up the creek and the airstrip road put the middle creek within reach of a longer day or an overnight.

Two other North Idaho waters go with this one. Johns Creek is a South Fork Clearwater tributary with a two-trout limit and its own steelhead story, and the Pack River drains the Selkirks into Lake Pend Oreille.

Frequently Asked Questions

Where is Cayuse Creek in Idaho?

Cayuse Creek runs 35.9 miles into Kelly Creek, part of the North Fork Clearwater drainage of north-central Idaho, in Clearwater and Idaho counties. It starts near 6,700 feet in the Bitterroot country and meets Kelly Creek at about 3,270 feet, four trail miles above the end of the Kelly Creek road. It drains the Bighorn-Weitas Roadless Area.

What are the fishing rules on Cayuse Creek?

Fish and Game applies the Kelly Creek and tributaries rule: all trout are catch-and-release, no bait is allowed, and barbless hooks are required. Bull trout are catch-and-release statewide. Brook trout carry a limit of 25 under regional rules, but the no-bait and barbless rules still apply. The creek is open all year.

How do you get to Cayuse Creek?

Drive Forest Road 250 to Kelly Forks, 48 miles from Pierce or 54 miles from Superior, Montana over Hoodoo Pass. Take Forest Road 255 about 11 miles up Kelly Creek to the trailhead, then walk Kelly Creek Trail 567 about four miles to the mouth. Toboggan Ridge Road 581 reaches a Forest Service airstrip on the creek four miles upstream.

When is the best time to fish Cayuse Creek?

July through October. There is no gauge on the creek, but the North Fork Clearwater gauge downstream peaks at 10,600 cubic feet per second in May and 7,900 in June, then drops to 2,500 in July and 1,100 in August. Hoodoo Pass usually stays snowed in until early July, and the Kelly Forks campground closes October 14.

Sources and Check Dates

• Idaho Department of Fish and Game, Fishing Seasons and Rules 2025–2027, second edition 2026: Clearwater Region pages 19–21, including the Kelly Creek and tributaries rule. Checked September 2026.
• IDFG Fishing Planner, Cayuse Creek: county, length, and rules block; IDFG hydrography layer for the creek’s course and mouth. Checked September 2026.
• IDFG, Fisheries Management Plan 2025–2030: North Fork Clearwater drainage table and the Clearwater narrative on roadless country and Dworshak Dam. Checked September 2026.
• IDFG, Management Plan for the Conservation of Westslope Cutthroat Trout in Idaho, November 2013: North Fork Clearwater section on the 1970 and 1972 rule changes, creel and snorkel surveys, and population status. Checked September 2026.
• USGS gauge 13340600, North Fork Clearwater River near Canyon Ranger Station: monthly mean flows 1967–2026 and water temperatures 1999–2026. Checked September 2026.
• USDA Forest Service, Nez Perce-Clearwater National Forests: Kelly Creek, Kelly Forks Campground, and Kelly Forks Cabin pages, the forest alerts page and Forest Orders 01-17-53-26-004 and 01-17-53-26-008 (Moose Mountain Fire), and the North Fork corridor travel planner. Checked September 2026.
• USDA Forest Service, Final Environmental Impact Statement for the Nez Perce-Clearwater Land Management Plan, Executive Summary, January 2025, and the forest’s recreation outstandingly remarkable value paper. Checked September 2026.
• Idaho Trails Association, “Trail Spotlight: Kelly Creek and Hanson Ridge,” October 2024, for trail conditions and camps. Checked September 2026.
• Friends of the Clearwater, Weitas Creek page, for the Bighorn-Weitas Roadless Area and the 1974 rule date. Checked September 2026.
• Wikipedia, Dworshak Dam and North Fork Clearwater River; OpenStreetMap for trail, road, and airstrip positions; USGS elevation point query service for elevations. Checked September 2026.