Bighorn Trout Shop: Late Summer Fishing Update

By Hale Harris

Late summer fishing has been good.
It’s been a great fishing year so far, and insect hatches have been good throughout the season. We saw a resurgence of PMDs and Yellow Sallies in July. Those hatches are over now. The black caddis hatch began in mid-July and is still taking place on the upper five miles of river. There are still a few of these insects farther downriver, along with some tan caddis and Baetis (Pale Olives). The Baetis are currently providing good dry fly fishing for the expert angler. Fish are eating both duns and spinners. The Baetis Student in size 22 is currently our top producer. Fish it on 6X or 7X behind something you can see.

It looks like the fishing is going to be challenging in the weeks ahead. Warmer water temperatures in late summer stimulate the growth of aquatic grass, and this grass reduces the amount of fishable water. Anglers are forced to concentrate on fast-water sections of the river, and competition can be fierce for the best water. Hopper fishing has been fair—we’re not catching large numbers of fish, but big fish are being taken. We’re hoping that the hopper fishing will improve, and that the Tricorythodes (tricos) mayflies come off in abundance. Tricos used to be one of the super hatches on the river, creating blanket hatches in September and October, but the drought years caused this hatch to all but disappear. After several high-water years in a row, it’s possible we’ll see a good hatch this year. If they return to their former glory, we’ll have some outstanding fall fishing.

An angler who can fish streamers effectively can do very well in late summer and fall. The key to successful streamer fishing is covering lots of water. It helps to be able to throw a lot of line, strip aggressively, and recast quickly. A sink-tip line of some type is usually preferred, especially if you want to get down in the deeper holes. The 24 foot sink-tip lines are especially good for this. As for fly patterns, I’m a big fan of patterns that utilize marabou or rabbit strips. These materials move well in the water and patterns tied with them look like bait fish or leeches. Black, brown and yellow, and olive seem to be the best colors. We have long-nosed dace in the Bighorn, so keep this in mind in regard to pattern selection.

This time of year, the Bighorn becomes an “angler’s river.” If you can get it done, the fishing can be great. If you’re a novice, you’re going to have to work for them. Hope to see you this fall.