Modifying Store Bought Flies

Contrary to popular belief, the flies that you buy from your local flyshop are not always as effective as they’re intended. Don’t get me wrong, there is a lot of thought that goes into designing flies and most of the time they are intended to be fished during a specific time-frame or hatch. So what is meant by modifying your flies? Fly modifications can be as simple as trimming the length of a wing, to as complicated as adding materials to the fly. I began modifying store bought flies a few years ago while fishing the salmonfly hatch on the Blackfoot River. While helping my buddy, who had very little experience on the oars maneuver through a wave-train, my high riding cat puke had sunken and become a drowned stone. To my surprise there was a 20" brown who thought that was a good looking meal. Instead of turning around and tying on a new cat puke that would float, I stuck with the now torn up sinking version, which turned out to be a good decision (there was a lot of pressure on the river that particular day which had the fish somewhat skeptical to eat on the surface). This is now my go to pattern on days during the salmonfly hatch when fish are somewhat skeptical to eat on top. What I like to do is trim the wing to 1/3 of its original length and part it. Additionally, I will throw it in some mud or dirt and smash it with my wading boot. This transforms the fly into a sunken stone, which will fish just under the surface, a truly effective modification on rivers with high fishing pressure.

Another popular fly in our store that I like to modify is Sam’s Big R Bug in both the salmonfly and golden variations (I know I’ll hear about this later).Sam originally developed this bug to imitate an egg laying, fluttering female adult in its final stage of life. Therefore this fly is somewhat bulky with oversized rubberlegs and schlappen hackle up front to create a large profile that will move water while it flutters. This is great when the fish are keyed into egg layers in the early stages of the hatch, but a lot of times as the hatch progresses and the fish have seen every store bought #4 salmonfly they begin to key into much lower riding profiled flies. With a few simple snips, the Big R Bug can be converted from a high riding egg layer, to a low riding natural. What I like to do is snip the front hackle on the underside of the fly, cut off the egg sac in back, and trim back the rubber legs to be just a little longer than the hackle.

The next modification comes from my favorite dry to fish, the chubby Chernobyl. I generally tie my chubs in all sizes and color combos, but when things get busy and I don’t have time to wrap some, I’m forced into buying them. There are a ton of modifications that I like to do to the chub depending on the time of day, the bug I’m trying to imitate or stream I’m fishing. The most popular modification that I make is coloring the back wing. Generally I will color the back wing black, but sometimes I’ll color it light purple or tan during bright days. Another popular modification I like to make is coloring the foam (usually black) or coloring the butt to add an egg sac to imitate egg laying stones.

A somewhat newer fly that I’ve began to modify is Keller’s Montana Mouthwash (I know I’ll hear about this one too). KK developed this attractor pattern to cover a wide range of underwater creatures: sculpins, leeches, stones, baits, you name it. I think that underwater profile of this bug does a better job imitating smaller, immature sculpins than, therefore it is one of my favorite sculpin imitations to fish early in the year. To make this fly strictly a sculpin, I will put the fly in the vise and trim the top part of the head to make it flat (the hook rides upside down, so the top of the fly will be the bottom in the water).This will give the Mouthwash the flat underbody profile that sculpins tend to have. I will also trim the rubber legs back to be just longer than the head. This will act more like peck fins than the longer legs will. Together, these modifications make the Mouthwash a killer sculpin imitation on all bodies of water.