Live & Learn

“You live and learn. At any rate, you live”  Douglas Adams

Over the 26 years we’ve been in business, I’ve witnessed a variety of conditions on the Bighorn River. This year looks like it will be another high-water year. Don’t panic. I’ve seen this before. I’ve seen high-water years and low-water years. I’ve even seen medium-water years, although these are a bit harder to recall. I’ve seen extremely low AND extremely high-water in the same year. I’ve seen years when they sprayed insecticide on the grasshoppers in nearby fields, and when the poisoned hoppers were blown into the river, they poisoned the trout. Just a few trout, mind you, but enough to cause major concern among the local populace. I’ve seen excessive moss and aquatic grass, marauding pelicans and ospreys, and anglers who harvested trout beyond the legal limit. This litany of challenging conditions and trout hazards could continue, but through it all the Bighorn River has proven to be anvil that has worn out many hammers. It just keeps producing an amazing number of brown and rainbow trout, year after year.

The river’s “unbreakable” quality owes itself to a variety of features. If you were going to design the perfect trout river, it would contain many of the characteristics of the Bighorn River today. Water chemistry is at the top of the list. The Bighorn is strongly alkaline due to the limestone geology of the canyon and upper river drainages in Wyoming. Alkalinity encourages moss and weed growth, which in turn provides habitat for aquatic insects and crustaceans. Crustaceans especially, put weight on the trout in a hurry.

Because the Bighorn is a tailwater fishery (below a dam), the water temperature is moderated to some degree—colder in summer and warmer in winter. Anchor ice doesn’t form on the bottom like it can in some streams during a cold winter. During a hot summer, when the water temperature in other rivers may top 70 degrees, the Bighorn stays in the optimal zone (55 – 65 degrees).

Current speed is not often considered, but the ideal trout river is not too fast and not too slow—I’ve heard that an average speed of 3.5 mph is about right. Too fast and it reduces trout holding capacity, too slow and the water temp heats up too quickly. Plus, you want the river to be “interesting,” not just a series of stagnant pools. You need riffles to aerate the water, deep water to provide security for large fish, and side channels for spawning. The Bighorn contains all these features along with a large volume of flow.

Speaking of spawning, the river contains an abundance of the right-sized gravel. The Montana Department of Fish, Wildlife & Parks has called the Bighorn “the most reproductive trout stream in the state.” The river has not been stocked in many years, and brown trout were never stocked in the river. They made their way into the Bighorn through feeder streams. Our wild trout are beautiful, and they fight hard. We receive many comments about the sporting qualities of our brown trout. They leap well and are colorful, especially in the fall. Other fishery agencies have expressed an interest in stocking the “Bighorn strain” of brown trout in their waters.

While our brown trout are special, rainbows tend to be the biggest and heaviest fish. On the average, they are in better condition than a brown of the same length. This is due to feeding habits. Rainbows utilize the crustaceans more than the browns. Rainbows will root around in the moss and grass in pursuit of sowbugs and scuds, while brown trout tend to concentrate on drifting food items. Also, larger browns prefer baitfish and unfortunately there are not a lot of baitfish in the upper river, just a few long-nosed dace. This being said, you will occasionally encounter a true trophy brown that has beaten the system. I assume these fish have begun feeding on small trout, plus carp and sucker minnows. These fish are usually taken by anglers fishing deep water with large streamer flies and 24’ sink tip lines. The lower river below Bighorn Access produces most of these trophies.

Let’s keep our fingers crossed in hopes that several of our insect hatches return to their former glory. Pale Morning Duns used to be the main event in July and August. This hatch was great because you could actually see your fly. What a concept! August also saw the Yellow Sallies (little yellow stoneflies) bring trout to the surface, and the trout slash at these fluttering insects with gusto. But in my opinion, the trico mayfly hatch used to be the best hatch on the river. This event occurred in September and October, with vast numbers of spinners rising up into the sky like smoky columns. When the insects mated, died and fell on the water, huge pods of trout fed ravenously. I often chose to fish double spinner patterns just to give trout a reason to select my fly out of the multitudes.

All the aforementioned hatches were better last season than they’ve been in years. I’m optimistic that this summer and early fall should provide great dry fly fishing. Of course, I’m assuming the dam won’t break and Japanese radiation won’t create trout and human mutants.