Dry Fly Case Study

We had an experience on the water a couple of evenings ago that I feel would make for a great learning exercise in trout behavior. Specifically in rising trout. In my experiences of fly fishing and guiding, I’ve learned that the more I learn, the less I know. This is why fly fishing can be so addictive. There is always a new experience, a different fish, and a lesson to learn. Another thing I’ve learned over the years is that fly fishermen tend to overcomplicate the hell out of the sport. We think over details that may or may not matter in the equation. We document dates, times, if the groundhog saw his shadow or not, weather, and so on and so forth. We tie fly patterns with miniscule changes to see if the trout liked the vibe better. We over analyze things over and over again, to the brink of insanity. Well today, let's push it past the brink of what a sane human would analyze. Here is my dry fly case study.

April 30, 2025. It was a Wednesday. The temperature hit a high of 63 degrees and the low was in the 40’s. We decided to do an afternoon float, to take advantage of the great evening baetis hatches we have seen lately. We put on around 4 and fished till dark. While the fishing was fantastic before the late evening, I want to talk specifically about a fish we encountered around 8 o’clock, rising to baetis dries. Yes, a singular fish.

After a couple of hours of unbelievable nymph fishing, we decided it was time to switch over to dry fly fishing, to target the pods of rising fish we were seeing on the flats and banks. We targeted a group of fish on a steep bank and caught one nice rainbow out of the pack, before I decided to hop out of the boat to get some footage. I love fishing, but lately I’ve found a lot of enjoyment out of documenting the fishing instead of throwing the flies. I jumped up on the bank and followed the boat downstream, waiting for Craig, (my Dad), to pick some fish to approach in the boat. I followed him down the bank for around 100 yards until we found a few fish that seemed worthwhile. I crawled on my hands and knees to the bluff of the hill to get a sight of the fish. This high angle on the hill gave me a perspective I don’t see often. I noticed some very subtle eats from the fish we spotted, which indicated to me that they were larger fish. On the Mo’ the splasier eats indicate a small fish, as they tend to slap the water with their tail, or roll on the surface when they rise, while the bigger fish are very methodical and gentle with their movements.

After sitting and watching for a couple minutes, I noticed the orange coloration on the side and figured they were brown trout. While both will be in shallow water, it seems like brown trout prefer shallower water than rainbows. Perhaps the rainbows sunburn easier. Who knows? I got my camera set up and keyed in on one specific fish, the bigger of the group. He was around twenty inches and had beautiful coloration. I also noticed a very peculiar habit he had. After every eat, he would swim upstream a couple feet before eating again. Most trout in moving water like to stay in the same spot and rise there continually, as it conserves energy. This fish was much more mobile than most. After watching him swim upstream about 30 feet, he turned right around and went back to where he started his ritual. Watch this first clip to see the behavior.

After he did this a couple times, he started settling into one spot, which I would attribute to an increase in baetis on the water. It seemed like he was searching for bugs to start, and then switched over to eating in a rhythm as the stream of bugs was more consistent. As he settled into his lane and got comfortable, I could see every one of his movements and decisions. He ate in a consistent rhythm, which should make for a catchable fish with the right timing. Craig threw a couple casts with a basic baetis dun pattern, to no avail. From my vantage point I noticed a behavior that I have never noticed from my normal angles of vision. Selective eating. This fish was selectively eating natural flies. I would see him eat three in a row, then rise up slowly, turn to look at a bug, then turn away sharply in an act of refusal. Every seasoned fly angler has had a dry fly refused before, but to see a natural refused? Talk about a harsh critic. Watch this fish refuse a natural in this video.

What this signaled to me, is that he was eating a specific form of dry fly. As I talked about earlier, his rises were very subtle. This usually means that the fish is not eating a dun or upright fly. They are targeting either a down winged spinner, emerger, or cripple. I rarely throw emergers, because I like highly visible dry flies, so now we decide if it is spinner or cripple time.

Choosing patterns is subjective, and everyone has their favorites. For personal use, and for my guests on the water, I try to use flies that you can see well on the water. There’s no point in throwing a dry if you can’t see it. I also really enjoy funky patterns that just look like a messed up mayfly. Cripples are great for this and are usually a good option for trout that seem to be feeding selectively. After around five minutes without an appropriate reaction from this fish, Craig decided to downsize his fly a bit, and tied on a favorite cripple pattern of his. A true confidence fly. He did not change his tippet size, or leader length, just a bug change. He took a couple of short shots to figure out his reach cast angle and drift length. When dry fly fishing, your first shot should always be short to get your bearings. After several short shots, it was go time. He threw a cast in the fish’s lane, and started feeding line. I watched his fly drift down 20 feet to the fish, who decided to move 6 inches away from the bank, out of the flies line and completely ignored it. He promptly picked the fly up and put it back on the water. I recorded the fly as it landed in the right lane, waiting patiently for a response from the trout. He locked eyes with the poor baetis pattern and rose to the surface. His nose broke the water as he let the fly drift in his mouth. As he took the fly back down to his watery domain, there was a long pause. Then Craig set the hook.

Trout are weird. They have their own habits and personalities. Some eat whatever you throw in front of them. Some just like shiny stuff. And others want a size 20 cripple baetis pattern with the proper reach cast and presentation. That’s the fun part. Every day on the water is a chance to crack another fish’s code. It’s what I live for. If you want to come and try to figure our fish out, we’d love to help. Mid June till the end of summer is when you want to be here for consistent dry fly fishing. It’s great right now as well, just at more specific times. We still have great spots available, and we are already marking some dates down for next season. If you're interested in a trip or just want to talk fishing give us a call. We’ll see you when you get here.