Hunt Trout on Fall Fly Waters

Set that rifle aside a sec – cool temps, lower flows make this prime time to hit streams.

by Matthew Dwonch

Fall has never felt more like summer. As I write this in mid-September, dozens of wildfires wreak havoc across the West, hammering Central Oregon, California and Idaho. Temperatures soar into the 90s, producing dangerously warm water in trout streams. This is all bad news, but don’t get me wrong: I still
love summer. Don’t we all? Who doesn’t get romantic thinking about warm July evenings, full moons and lunker brown trout? Most of us outdoorsmen and -women happily endure the struggles of summer to reap the benefits. And therein lies the beauty of fly fishing the American West. Each season offers its unique challenges, which when solved can produce beautiful rewards. This is true especially of fall, which many seasoned anglers would call the greatest fly fishing season of them all. Last month we focused on Northwest alpine lakes. This article is a continuation of sorts, but will focus
instead on streams and rivers.

DON’T UNDERSTAND THE draw of fall fly fishing? That’s OK! For much of my life, neither did I. I once associated fall with MLB playoffs and Sunday Night Football. That is until I stumbled upon a beautiful little trout stream nestled on the edge of the Frank Church Wilderness several Septembers ago. It’s in a remote location, and while I had not previously laid eyes on it, I had heard rumors that it provided refuge to a population of native bull trout. I knew I had to see them with my own eyes. I became more and more enthralled with stories of bull trout until one day it became too much. I packed my gear and departed for the creek early one September morning. My old Toyota bounced along a rutted dirt road for several hours until I arrived at my destination. It was an eerie scene. A beautiful freestone creek rolled down a steep canyon in front of me. If this had been a month earlier, there would have been voices
echoing around each corner, as fly fishermen jostled for position over the sweetest honey holes. Instead, I was met with complete and utter silence. I remember thinking to myself, “I could get used to this.”

I made my way onto a trail that meandered alongside the creek, giving me a bird’s-eye view into
deep blue pockets of water. I spied migrating Chinook salmon, as well as the occasional trophy bull trout cruising by. It wasn’t long before I found a spot that was to my liking. I tied an Adams Irresistible onto my 5X leader and pushed down the adrenaline every fisherman feels when casting into novel water. A crisp breeze threatened to interrupt my first cast, and the Adams missed its target by several feet. Frustrated, I decided to start over and try again. When I whipped the fly off the water, I found a healthy 12-inch westslope cutthroat attached. I knew then I was in for a treat. Over the next three days, I enjoyed solitude, excellent fishing and refreshing fall weather.

PERHAPS THE GREATEST reward for breaking the fly rod out in the fall is the promise of relative solitude on most rivers and streams. Labor Day marks the end of summer, but if you’re a fly fisherman, it marks
the beginning of something else entirely. It marks the start of a mass migration. Each Labor Day, watch
and witness as masses of summer recreators retreat into the comfort of the homes from whence they came. That’s slightly dramatic, but seriously, the vast majority of summer crowds seem to simply vanish after Labor Day. This leaves your favorite rivers and streams conspicuously lonely, a perfect opportunity for diehard fly fishermen to seize upon.
As previously mentioned, this past summer was brutally hot. In my neck of the woods, temperatures
soared to above 100 degrees for nearly a month straight. This made many folks upset – and it put some local trout populations in dire straits. Mass die-offs were reported in several watersheds. If the heat didn’t outright kill the fish off, it certainly kept responsible anglers off the water for weeks at a time. The good news is that those roasting days on the water should be behind us. Though recent Octobers have seen notable late late-season heatwaves, once the mercury reliably dips into the 50s, trout are happier, and thus so should you be. Add into the mix spectacular fall foliage and scenery, and you’re looking at a genuinely good time.

LIKE ANYTHING, THERE is a price of admission with fly fishing rivers and streams in the fall. The price
you pay is generally manifested in decreased fish aggression. Biologists have found that trout generally feed less frequently and less aggressively during the fall months than in spring or summer. Although it is not exactly understood why this is, it can almost
certainly be attributed to lower flows and decreasing water temperatures.
Of course, there are situations in which this logic does not apply at all.
Some fish can be extremely aggressive in the fall. Most of these cases relate to spawning. Rainbows
and cutthroat spawn in the spring, but brook and brown trout spawn in
November. In the heat of spawning, they are dormant and lethargic. Shortly before this time, however, say in October, these fish become increasingly aggressive and willing to strike. They are not eating out of hunger, but out of predatory instinct. Think about steelhead. Steelhead fishing in the Inland Northwest occurs in fall and spring as these fish migrate from the ocean back to their ancestral homes hundreds of miles upstream. They are on a mission to spawn, so he idea is to throw something flashy and irresistible in front of these fish until they cannot resist attacking. Brook and brown trout offer similar opportunities in October and are likely to chase streamers and other large flies with malicious intent. Speaking of which, fall is the perfect time to cast larger fly patterns. Streamers, stimulators and large terrestrials are quite effective. Fish tend to hold in deeper pockets and pools of water starting in September. An annual decrease in irrigation needs spurs this reaction. Tailwaters, or rivers and streams that are dam-controlled,
see a drastic drop in flows following the end of summer. Watershed managers start to gather water into reservoirs in preparation for next year’s summer irrigation needs, which leaves flows down in the tailwaters. This has drastic effects on fish behavior. Usually, these effects are fisherman-friendly. Fish tend to be more tightly congregated in a few large pools during the fall rather than spread throughout the entire tributary. The drop in water flows also allows access to sections of the river that were previously dangerous or impossible to access. New spots, stacks of fish and streamers? Yep, it sounds like paradise to me too!

STREAMERS ARE ALWAYS fun, but on warmer days, consider reaching for a dry fly rather than a streamer. Mayflies hatch throughout fall, with the most numerous by far being the small olive variety. Blue-winged olives sized 18-22 are my go-to fly in the cooler fall months. If there is a hatch, it’s often going to involve olive-toned mayflies. Caddisflies are also a resilient bunch and hatch into late October.
The famous October caddis is a large orange bug that trout find irresistible.
Adults typically emerge on larger streams from late September through October. If you happen upon an
October caddis hatch, buckle up for an outrageous day of fishing. Terrestrials are also in play up until the first frost of the year, and sometimes beyond. Grasshoppers are a fair bet on some rivers in dry climates, but beetles are just as important a food source for many trout. A basic, size 16
black foam beetle will often suffice. If you are determined to continue your summer fun, grab a Joe’s Hopper instead, the greatest hopper pattern I have in my arsenal. Now, back to streamers. Fishing
with streamers is a boom-or-bust business in my experience. The takes are few and far between, but they are downright ferocious when they happen. As a bonus, fish that hit streamers tend to be larger and more predatory than their dry-fly-eating buddies. I have heard it said that the color of the streamer thrown is more important than the pattern. I tend to disagree. I have fished every color of streamer imaginable under light and dark skies and to tell you the truth, I have not noticed a significant difference in productivity between colors. I adhere to a more “right fish, right time” attitude. However, certain patterns do stand out to me as excellent streamers. Classics like the black Woolly Bugger, Olive Zonker and Clouser Minnow rank near the top of my list.

AS BLAZING HEAT continues this week in September, I can’t help but long for cooler temps, low flows and crisp fall air. It’s about time to get lost on a cool lonely river with nothing but a fly rod and some willing fish. I hope you find that place this fall season as well. NS