Late Summer Fishing Update

This has been an interesting year on the Bighorn River. I know every year is different and therefore interesting, but there really have been a few unique aspects to this season. To begin, we were confronted with one of the highest snowpacks on record. Billings set a snowfall record and our drainage flirted with 175% of normal at times. We heard reports of caribou and muskox making their way south from Canada. All of us were bracing ourselves for record flows in June. But unlike some years, when river flows weren’t bumped up until late May, the Bureau of Reclamation decided to get ahead of the runoff so they raised flows in April—8,000 cfs, something we’d never seen before this early. High water and cool spring temperatures also came to the rescue. We toasted the Bureau’s proactive efforts. Then water flows were reduced and the algae started to bloom. Not the Bureau’s fault, mind you, simply something that happened due to a churned up lake and other water chemistry factors. The excessive algae choked off certain holes and made life challenging for many anglers. Local guides started to call suicide hotlines. Then lo and behold, we find out miscalculations had been made by the Bureau and the water has to be raised back up again. Up it comes to 7,500 cfs. Not to worry, this flushed out the algae and life was good again. Well, not completely good.

Bighorn Trout Shop guide, Shawn Paul Williams, nets another brown trout for his clients.

Our PMDs and Yellow Sallies never really showed up in significant numbers. Maybe they were washed downriver, and people in Omaha are scrambling to match the hatch.

Anyway, enough water-flow history—what does this all mean? Well, extended periods of high flows tend to churn up the lake. All that water moving through the system doesn’t allow particulates to settle completely. I use the word “particulates” because it sounds better than “a bunch of crap floating in the water.” Particulates tend to create favorable conditions for lake algae blooms with the result being greenish water coming out of the bottom of Yellowtail Dam. Also, higher flows tend to bring water temperatures up earlier in the season. The fish don’t mind—they’re more active and grow faster as water temps approach 60 degrees. However, aquatic grass grows faster with the warmer temps, so as late summer approaches the grass becomes a problem for anglers.

ANYWAY, besides a little whining, we’re dealing with the grass by nymphing the faster, riffle water. Various runs are very productive, especially in early afternoon when the caddis are active. Some of us are throwing streamers. We’re also looking for rising fish. The black caddis are waning, but they’ll be around for awhile, as well as Pale Olive Baetis.

Tricos are hatching on the lower river below Bighorn Access. It won’t be long before Tricos are the main event on the upper river. Trico mayflies bring up more fish than any other hatch on the river. Because the fishing can be technical at times, it takes an accomplished angler to take full advantage. That’s just the way it is when you’re fishing spinner patterns and 6X tippet. Be aware that Bighorn River fishing guides are fairly polite, and usually won’t tell their clients, “Boy, your casting sucks.” Guides may wander off into the brush at times to scream and bang their heads against a cottonwood tree, but they will usually regain their composure by the time they get back to the river. I mention this in order to encourage anglers to engage in casting practice before they show up for their guide trip. Standing behind a ravenous pod of trout that are slurping trico spinners in the sunlight is as good as it gets. September should be prime time.