Crowsnest River Salmonflies

The salmonfly hatch is in full swing on the Crowsnest River and fishing conditions couldn’t be better. It’s not very often where the river is clear and fishable during this elusive hatch. It is this year, though. This stonefly hatch occurs every year but it usually coincides with the spring runoff, a time where the river is running high and discolored. Everything has come together perfectly this time around, and who knows, it might be another 10 years before it happens again.

Let the Hatch Begin

I’ve been checking the river almost daily for the past couple weeks for signs of the big bugs. Last Monday, there were about a dozen stonefly shucks on the concrete abutments on the small bridge downstream of Hwy. 3. During the week, only a few more stoneflies crawled out of the river to hatch. I was beginning to wonder whether it was ever going to happen. Then, on Saturday night, under the cover of darkness, they crawled out of the river en masse. By Sunday morning there were salmonflies everywhere on the lower section of the Crow.

Stonefly shucks on bridge abutment

An Exciting Event

Unless you’re a fly angler, you probably don’t understand what all the fuss is about, or why this insect hatch can cause such a stir. If you are a fly angler and have experienced such an event, you know why people get so excited this time of year. These stoneflies (Pteronarcys californica) are giants, the largest of the various species that inhabit the river. When the salmonfly hatch begins on the Crowsnest River, trout take notice. And so do anglers.

Salmonfly adult

Nymph fishing can be productive before, during, and even after the salmonfly hatch. The naturals spend up to four years in the river and are available to trout all season long.

Salmonfly nymph and imitation

Nymph to Adult

Each spring, when the time is right, the nymphs crawl from the river onto shore, where they begin their amazing transformation into winged adults. The whole process may take an hour to complete. The nymphal exoskeleton splits open across the back and a winged adult, a salmonfly, slowly pulls itself free. All that is left behind is an empty, paper-thin shuck.

This nymph crawled 30-feet from the river, then 4 more feet up a fence post to hatch

Shucks upon shucks

The name salmonfly refers to the salmon-orange coloration of the adult’s body. They are huge and can measure more than two inches in length. There’s a lot of protein in one salmonfly. Trout love protein and will gorge themselves on these insects when given the opportunity.

Female salmonfly, with egg cluster and shuck below

Returning to the River

Once they have mated, female salmonflies return to the river to lay their eggs. They will often release their egg clusters while flying above the river, but will sometimes land on the water to deposit their eggs. The life cycle of this year’s salmonflies is nearly complete, but others will soon begin their lives among the rocks and boulders at the bottom of the Crowsnest River.

Adult stoneflies are sometimes blown into the river by strong winds, or inadvertently fall onto the water from streamside vegetation. If water clarity is at least a couple feet, trout will be able to see these insects floating on the river. Once they are on the water, they are fair game and easy targets for hungry trout. This is what fly anglers dream of – the opportunity to catch trout on large, bushy dry flies.

Salmonflies creeping across my camera

On Monday, I was able to get out on the river for a good part of the day. I had my fishing gear with me but spent most of my time photographing salmonflies along the river. They were all over the place and at times were crawling on my camera equipment, and on me.

Salmonfly on camera and bush

Sam landing a nice rainbow

During the afternoon, I bumped into a couple of anglers, Sam and Susan, who had caught a few fish on nymphs. While we were talking, Sam hooked and landed a nice size rainbow trout on a large, rubber-leg stonefly nymph pattern.

Mark fishing a riffle

 A Perfect Day

Later on, I headed a bit further downstream and ran into a couple of my friends, Gary and Mark. Gary was heading home for the day and said the dry-fly fishing had been quite productive for him. Mark had just arrived and was rigging up his fly rod. I had about an hour to fish, so I climbed down to the water and tried a large, foam-wing dry fly. Right off the bat, a small rainbow trout grabbed my fly on the surface. The fish was on for a couple of seconds before the hook pulled free. I worked my way upstream, casting into the water flowing along the willow-lined bank. Two larger trout rose to my fly but didn’t connect. Finally, along a quiet seam, where the river turned at a bend, another trout rose to my dry fly. This time, it stuck and I had my first trout of the year caught on a dry fly – and a salmonfly pattern, at that!

A fat Crowsnest rainbow trout caught on an adult salmonfly pattern