Anglers looking to cast streamers can leave the large meat box in the closet. Right now is prime time for small streamers. There is a predominance of small fish in the river now from this year’s spawning cycle. Anglers willing to do the math can build a solid case for fishing small streamer flies now.
Colorado Parks and Wildlife is imposing closures for spring spawning activities on specific waters from March 15 through May 15. Given these dates, anglers can do the math. Small variables like water temperature can lengthen the gestation period before eggs hatch into fry. But it is a period of about 60 days between egg laying and hatching.
The fry are the first stage of rainbow trout development where the egg sac is still attached to the belly of the fry. Once the egg sac has been absorbed, the small trout are in the nursery stage. Almost an inch in length, the fry will swim around the bed. High water will begin to move them as they grow.
Regarded as fry up to three inches or longer, the small fish will begin to develop parr marks. Parr marks are the characteristic spots that color small rainbow trout. During development, parr marks are lost as they mature into fry.
The period between a newly hatched rainbow trout or fry and fry is the window we are currently in. There really aren’t as many fingerlings or yearling trout as fingerlings. The fry learn to swim and the fast currents take the little scarred minnows on an uncontrollable ride. The high number of small trout entering the food chain is a pseudo-hatching so to speak.
The fast-swimming brown trout make easy meals from the highly targetable and extremely visible morsels struggling in the rushing currents. Confronting a monstrous, full-grown, hook-toothed brown trout is a losing game for rainbow babies.
The window is therefore open for the new series of rainbows to throw the gauntlet until summer. Anglers looking to cast streamers should convert their knowledge of rainbow trout development into smart choices for fly selection.
Small rainbows range from 1 inch to 3 inches. Their sides have very visible spots along the length of the fish. They don’t swim very well and therefore seem to be in trouble. Present your flies to mimic “wrestling” for a realistic presentation.
Gary Lafontaine was a great fly fisherman, teacher and person. His writings and videos have taught worlds of anglers and given a thirst for fly fishing that I haven’t quenched in over 30 years of fly fishing. He believed that a struggling, weak and injured baitfish could not swim with strength. Thus, he deliberately cast for the shore when he float-fished and repaired downstream. The downstream repair would pull the streamer with the current the same way an injured or easy-to-eat baitfish would swim.
It’s always a good idea to try a different recovery when you start streamers. This presentation can be a killer with the drop in flows still keeping the water in the somewhat high category but definitely going down. Trout saw lots of small fry blown into the river. Ambush points, rock obstacles, and woody debris all create opportunistic strike positions sought by predators.
Fishing the little streamer flies on a short leader. Small flies don’t need a lot of weight to sink them, but a downward leading line will pull the fly down with an enticing drop. The change in depth a few feet from shore is good water for fishing.
Targeting obstacles with a light color, but striped to mimic parr marks, the streamer can draw in healthy opponents. The brown trout are ready to be fed and the little rainbow fry are just the big bite of protein they are used to seeing in the river.
Now is not the time for your bushy, articulate streamers. A little whitefly with a glue gun egg sac is a unique streamer to use for this time of year. But any small streamer who swims attractively can mimic the early stages of rainbow trout development. Take the little ones out, you’ll be glad you did.
Michael Salomone moved to the Eagle River Valley in 1992. He began guiding fly fishing professionally in 2002. His freelance writing has appeared in magazines and websites including Southwest Fly Fishing, Fly Rod & Reel, Eastern Fly Fishing, On the Fly, FlyLords, Pointing Dog Journal, Upland Almanac, Echo Website, Vail Valley Anglers and more. He lives on the shore of the Eagle River with his wife, Lori; two daughters, Emily and Ella; and a pair of yellow Labrador retrievers.