A strong argument for tying your own flies is the ability to design a fly that is different. When fishing pressured streams, I like to think my fly doesn’t match every other angler’s offerings. Maybe theirs are better, but mine are at least different.

When fishing pressured streams, I at least like for my fly to be different.
The owner of a local fly shop once told me how many thousand size 14 Pheasant Tail nymphs he sold every year. I forgot the exact number, probably because I have trouble with math in big numbers, but the message was clear. The fish already had a crack at thousands of size 14 Pheasant Tail nymphs, so one more might not look that appealing. At some point, even bakers in a donut shop quit sneaking bites.
Each season, I pick one or two patterns in my box and work on them. They are usually flies I like but think they could be better. I’ll give you an example.
Several decades ago, I started fishing a popular stone fly nymph that became one of my go-to flies. I used it and caught fish. But I thought it could be improved.

Starting with a classic fly, I experimented by changing one part at a time.
For starters, I lost a lot of them on the bottom. The stone fly was weighted and snagged on the rocks and sticks where stone flies were supposed to be fished. So the first thing I did was turn the hook over. Dai-Riki makes a streamer/nymph hook (#700B) that is bent about a third of the way back from the eye. If you wrap lead or heavy wire on that front third, the fly rides with the hook point up. This did reduce hang-ups on the bottom though tree limbs on my backcast were still in play. Some things you can’t fix.
My next adjustment to the fly was an attempt to add life to it. For instance, when this fly was designed, biots were used for the tails and legs. Biots are about as lifeless as a mannequin at Macy’s, so I replaced them with rubber legs. Now the fly had some movement even on a slow fall.
The thorax on the original was tied with chenille and it seemed that loose dubbing might be more effective. Once dubbing gets ragged from being chewed on by a fish the fly seems to improve. So I changed that as well.
After fishing the new pattern, I wanted just a little faster sink rate so I added a tungsten bead head. I used dull colors to keep the look as natural as possible.
After each change, I fished the fly a few times to confirm the fly had improved. On occasion, I took a step back but by the end of the season the new fly had found its way into my secret fly box.
When I compare this pattern to the original, about all that stayed the same was the peacock herl on the body. I never changed that part as I believe a trout would eat a grilled cheese sandwich if you put herl on it.
Still, I never set out to create a new fly. My intent was to make a good pattern better and over time it evolved into something totally different. As new materials become available, many classic flies will be targets for upgrades.
After a number of seasons, my fly box has become home to a few secret flies. These are the ones that I’ve invested time in, have gained my confidence, and may be just a little different than a size 14 Pheasant Tail.
My secret streamer pattern has produced most of my best brown trout. You would recognize it if you saw it but you might not pick up on the changes as they are somewhat subtle.
The hotspot I added is not overwhelming but it’s a color browns like. It also contributes something to the original pattern that might look just enough different to the fish.
The second change is almost imperceptible. I’d had some short strikes on the original and decided the wing was too long. So I shortened the hair wing to stop just past the bend of the hook. Then I lengthened the few strands of Flashabou so they would flutter more freely now that they weren’t confined by the hair wing. The end result is a compact sculpin imitation that is bite-sized and has some life.
Not long after modifying the streamer, I found myself on a stream in the North Carolina mountains a bit wider than my casting range. Heavy rain had made it difficult to wade and the main currents better for kayaking than fishing. Still, I had driven a good ways and wanted to fish.
The new streamer was a logical choice to start with. It had some bulk and weight, so I shortened my leader and tied one on.
I found a deep hole where I could wade the close bank though I couldn’t see my feet through the suspended silt. The water had the translucency of milk so I had to test each step with one foot. Even close to the bank I was in water up to my waist. The only fishable section was directly upstream but looked like the sort of place a brown might hold. The bank was undercut and the water slowed against it.
Casting straight upstream, I let the streamer find bottom before working it back. I gave it short jerks the way I imagined sculpin moving. In short order, I felt a take as I gave the streamer a twitch.
The fish seemed satisfied to slog it out in the slower water. Soon a nice brown slid into my net with the streamer protruding from the corner of its mouth like a half-smoked stogy. With a twist of the hook and a dip of the net, he was soon back under the bank.

Most of my best brown trout have been on my secret streamer.
Feeling my way upstream with my feet, I continued to fish along that edge picking up the occasional brown trout. By the time I had used up the wadable section, I had four nice browns on the streamer. All four were among the best I caught from the river that year and the sculpin imitation became one of my secret flies.
I’m one of those fishermen who really could fish the local streams for a season with just a dozen patterns. When you rely that heavily on each pattern, it makes sense to invest time improving them. Then, each fly becomes something of a treasure. You protect the secrets in your fly box, not wanting to give them away for free.

Secret flies should be carried in a box without a clear lid.
This extends to climbing trees to retrieve flies from low limbs, wading out to snags and reaching into cold water for a snagged fly, and crawling around on your knees in the parking lot looking for one you dropped while tying it on in the dark. When the loss of your secret is at risk you spend more time trying to protect it by finding the fly.
I’m contemplating which fly to work on this season, to provide a few tweaks and eventually produce a better pattern or at least one that’s different. I’m leaning toward a size 14 Pheasant Tail. After all, it’s a good pattern that might be made better. Besides, even a baker in a donut shop will take a nibble if you add a few sprinkles.
Jim Mize continues to chase fish with secret flies. His award-winning books of humor and nostalgia for outdoorsmen can be found on Amazon or you can get autographed copies at www.acreektricklesthroughit.com. You can also purchase Jim’s books here on Rivers and Feathers “Books” page.