The Incredible Crane Fly Larva – Part II – A Killer Pattern for Large Trout
After reading about how trout love to eat crane fly larvae, I went looking for them to see what all the fuss was about. Not far from my home in Boulder, Colorado, flows a small stream called Boulder Creek. I went down to the creek and started dumping rocks looking for crane fly larvae. Lo and behold, the stream was laden with the larva of the giant crane fly (Tipula abdominalis). I collected a few samples, put them in a quart jar, and took them home to my fly tying bench. You can imagine how excited my wife was when she saw the jar of “worms” in my fly tying bench. Don’t worry though, he had come to expect such strange behavior. A jar full of “worms” was always preferred to roadkill.
I started experimenting with different combinations of Ligas dubbing (Ligas dubbing produced a more translucent effect than other dubbing materials) until I had an absolutely perfect mix to match the color of the larva To duplicate the translucent effect of the larva of the crane fly, I used a loop dubbing technique to tie the imitation. A Mustad 9672 #2 hook was the perfect length to match the size of the crane fly larva I had in the jar. When I was done, I dropped the imitation in the jar to see how close it had come to matching the real “bug.” My imitation was so perfect that I couldn’t tell the difference between the real larva and my imitation except for the hook sticking out of it! I couldn’t wait to try it. I went fishing on my favorite river, the North Platte in Wyoming, about 15 miles upstream from Saratoga, Wyoming, on a section of state lease called “Treasure Island.”
Later, at the end of my fishing day, I ran into two other fly fishermen in the parking lot and asked if they had any luck. Expressing their disappointment, they informed me that they had only caught two trout. They complained that the river was too high and the water too cloudy. They were locals and they assured me that the fishing would improve a lot as soon as the runoff stopped; then they asked me how I was. I proudly responded; “I had a great day. I caught about 30 fish.” They both reacted in amazement and of course they wanted to know what she was wearing. They were both very surprised when I showed them my crane fly imitation.
For years I tied flies for the Great Rocky Mountian Fur Company of Saratoga, Wyoming, and they used my pattern of crane flies extensively. Tom Weirsema, the owner of the shop, told me that the first time he caught my skipper for crane fly larvae, it produced the largest brown trout he had ever caught on the North Platte. I also sent the crane fly larva pattern to Rod Walinchus of Rawlins, Wyoming (The Great Divide Flyfishers) for his book: “The Flies of South Wyoming.” After the book was published, Rod felt me a copy of the book. He included a note saying that he had caught an 8½ pound brown on the fly on his first cast! About a year later, I saw an article in the Rocky Mountain News written by an outdoor writer extolling the fishing properties of an “ugly-looking olive cigar.” Word had gotten out.
As I mentioned earlier, a crane fly larva is translucent, and three colors will mimic most larvae: light gray olive, tan, or dark olive. The fly is easy to tie and has a very simple design. It is shaped like a tiny cigar.
I tie them weighted in sizes 2, 4, 6, and 8. For the South Platte in Cheeseman Canyon near Decker’s Colorado, a size 6 and 8 in tan and dark olive colors is preferred. However, in larger rivers like the North Platte, the Green, the Big Horn or the Colorado, for example; Sizes 2 and 4 are better. The further north you go, the larger the crane fly larva becomes. In Montana I fish only the very heavy size 2 in light olive drab.
There are two presentation methods for the fly fisherman to fish for crane fly larvae: one, you can let them drift as you would any other nymph; when fishing with a nymph. Or two, you can fish them on a sinking line using a short 6-foot leader with a hand-spin slow retrieve. I have had tremendous success with both methods. For really wide water, the sinking line method will take the fly to places that would otherwise be very difficult to reach with a nymph style of fishing.
The best time to fish for crane fly larvae is from the beginning of May to the end of July. I have fished using the pattern in every season except winter.
Where to fish for crane fly larvae? I start at the head of any race just below the rapid. I like to throw the fly in the fast water above and let it wash away on the run. Don’t be surprised if you get an immediate take. From there, I try all the fishable spots throughout the race.
When fishing the crane fly on a sinking line, use a size 2 or 4. Move the drift for the first half of the cast and swim the second half. The largest pattern will be taken as crane fly larva and/or minnow. The sinking line technique is very deadly and will produce the biggest fish in the river.
As for a “pretty” fly, the larva of the crane fly is not very impressive to look at, however trout do not know this. They just want to eat it. Use a minimum of 3X or stronger tippet. The most dominant fish in the stream are usually the first to try it; so hold on and make sure you have your camera with you.