Fall Fishing on the Horn

“Everyone talks about the weather, but nobody does anything about it”
— Mark Twain

The days are getting noticeably shorter. There’s a little bit of a chill in the morning air, just a little. Of course, I may be imagining this chill because I recently read that the Farmer’s Almanac is predicting a very cold winter. The article said that, “since 1818, the Almanac makes predictions by triangulating the positions of the planets, sunspot activity and cycles of the moon.” Who are these farmers, and what do they farm? I’m trying to imagine the following: “Hank, have you fixed the fence on the back forty?” Martha asks with concern. “Not yet, Dear. I’ll get to it right after I triangulate the planets and check on sunspot activity.”

Anyway, not only is the Almanac predicting a cold winter, but also significant snowfall for most zones. They were a bit noncommittal on snowfall predictions for the northern plains, but the message seems to be: Get your fishing in before temperatures plummet.

The Bighorn has been great. We have a logjam of hatches ready to provide good fishing in September. Pale Morning Duns are still hanging around. Anglers are reporting good dry fly fishing on the upper river (Afterbay to Mile 7) using Snowshoe PMD and PMD CDC Compara Dun patters. Don’t confuse any of this with the FDIC.

Black caddis are fast becoming the main event. The fish are eating black caddis pupa patterns throughout the day, afternoons being best. In the afternoon you will encounter caddis emergences, and toward evening, egg-laying flights. Both of these events can provide world-class fishing. I seem to do better on sunny days, rather than cloudy days when it comes to black caddis, but this is not always the case. A CDC Black Caddis work great for a dry pattern, as does the Hemingway Caddis. The Hemingway is difficult to see but a great picky-fish fly. The olive Flash Back Pheasant Tail Nymph is still my favorite pupa pattern. I usually cut off the tail—probably doesn’t matter, but it makes me feel better.

Tricos are bringing fish to the surface in the morning, especially on the lower float sections. I’ll write more about them in another blog. I’ve had a few good Trico mornings already, from Mallards to Two Leggins. People are fishing them on the upper river too, especially near Bighorn Access. Soon they’ll be the hatch to focus on. You might want to get out there early to fish the duns. The spinner fall happens a little later in the morning depending on air temperature.

And thank God for the Baetis. They’ve been around all summer, their little gray wings glistening in the afternoon sun, looking like perfect miniature sailboats as they dance on the crystalline currents, fulfilling their role in the circle of life. (I thought that by waxing poetic, I could communicate my appreciation for these little insects.) Many of them never make it to the “glistening wings” stage, and the trout take full advantage of this. Emerger and stillborn patterns like the Student are tough to beat. We expect the Baetis to continue sputtering off, and to increase in number later in the fall.

Nymph fishing will remain productive. Aquatic grass can become a problem this time of year, but because of the cold water temperatures, we don’t expect it to be as much of a factor. The fish are eating Baetis nymphs, sowbugs, PMD nymphs and caddis pupa.

Many people ask me, “When is the lake going to turnover?” For those of you who don’t know, here’s a brief explanation of lake turnover from a National Geographic website:
“Lake turnover is the process of a lake’s water turning over from top (epilimnion) to bottom (hypolimnion). During the summer, the epilimnion, or surface layer, is the warmest. It is heated by the sun. The deepest layer, the hypolimnion, is the coldest. The sun’s radiation does not reach this cold, dark layer.
During the fall, the warm surface water begins to cool. As water cools, it becomes more dense, causing it to sink. This dense water forces the water of the hypolimnion to rise, “turning over” the layers.”

During some years we experience an algae bloom near the surface of the lake. When the turnover occurs, the greenish, algae-colored water, along with other suspended particulates, begins coming through the bottom of the dam. Depending on the severity of the algae bloom, this can have a negative effect on the fishing, although oftentimes it affects angler’s attitudes more than the fishing itself. Lake turnover often takes place in October, when air temperatures drop significantly.
During some high-runoff years the lake becomes full of suspended sediment and this begins making its way to the river in September or October. The issue is not so much lake turnover, as it is a churned-up lake. All this being said, I’m not expecting much of a problem this fall. (Don’t quote me on this—I picked the Denver Broncos to win the Super Bowl last year.)

So it’s shaping up to be an outstanding fall fishing season. Low, cold water creates dry fly opportunities. The trout are fat and happy. Streamer fishing is turning on as well.

An angler fishes the fall Baetis hatch