Fall Fishing Frenzy in Big Horn, Montana: Trout, Walleye, and More on the Rise

Big Horn Montana woke up crisp and clear this September Sunday, with overnight lows dropping into the high 40s and a light breeze drifting through by dawn. Sunrise hit at 6:38 a.m. with another golden shot expected at sunset, 7:39 this evening. We’re getting real hints of fall now, as the nights have cooled off and the days settle into comfortable, fish-chasing conditions. No tides to report this far from the coast, so river flows and reservoir levels are what matter most. On the water, local anglers are reporting trout activity is on the upswing, especially during the middle of the day after things warm up just a touch. Montana Outdoor’s latest report from September 6th points out that the hopper-dropper combo is still drawing energetic strikes, but a change is in the air—blue-winged olive mayflies are starting to make appearances on cloudier afternoons. If you’re a fly angler, keep a box ready with #16-#18 blue-winged olive dries and parachute Adams, and don’t put away those foam hoppers just yet. For subsurface, a bead-head pheasant tail or a smaller copper John below the hopper is a steady producer. If you’re aiming for walleye, Fort Peck continues strong according to the latest Montana Outdoor Radio Show recap, where deep-running slow-trolled crankbaits and crawler rigs are pulling strikes from the ledges and drop offs. Smallmouth bass are still hanging deeper too—try jigs tipped with soft plastics on the rock piles and points. Out at Canyon Ferry and Tongue River, perch and crappie mixed bags are showing up near weed lines and brush piles, responding well to small minnows, panfish jigs, and even a classic worm under a float for the kids. In the Big Horn proper, drift boaters and shore anglers alike have picked up some healthy rainbows and browns this week, especially in the after-lunch window as the sun coaxes bugs off the water. Locals say streamers in olive and white—zonal buggers or sparkle minnows—are pulling bigger fish out of shadow pockets and cut banks, especially when fished slow first thing then a touch faster mid-day. For bait, the tried-and-true nightcrawler below a split shot is always a staple near the afterbay and in any of the deeper runs. Folks tossing lightweight spoons or little Rapalas are landing mid-size browns and occasional cutthroat. If you’re looking for a hot spot, the Afterbay section just below the dam is a perennial favorite, especially on a cool, misty morning. The stretch downriver near Soap Creek confluence has had solid numbers of active trout as well, both from shore and by boat. For the adventurous, hiking into the lower canyon gives you a shot at wild fish in less pressured water, but watch for mud and loose rock after last night’s brief shower. Fish stories from this past week include several rainbows pushing 18-19 inches, a surprise walleye caught north of the Bighorn ramp, and lots of action on chunky browns in the 15-16 inch range. Mountain lakes in the Absarokas to the west are also picking up, This content was created in partnership and with the help of Artificial Intelligence AI.