Fly Fishing with Salmon Flies 101
It's finally June, which marks the beginning of a special time of year for anyone who knows anything about anything. It's Salmonfly time on Montana streams'. The recent wet weather has delayed the emergence of these giant humming-birdesque bugs, but the first bit of warmer, dry weather will get um active, that you can count on. So here's a quick and dirty run down on the life cycle and effective techniques during the Salmonfly hatch.
Life Cycle: Salmonflies (Pteronarcys Californica) in the nymphal stage are considered stoneflies and will not be considered a salmonfly until they have become an adult.
Stonefly nymphs require highly oxygenated water to mature, so it isn't a big surprise that they're found in fast flowing, oxygen rich streams. During the colder winter months, the stoneflies burrow themselves deep into the bed of the stream to escape from the potentially hazardous cold water conditions. As the water begins to warm in the spring months, the stoneflies emerge from the stream bed and cling to the underside of bedrock within highly oxygenated runs and riffles. This is where the stonefly will spend most of his/her underwater life (3-4 years) feeding on algae and other microscopic matter.
As the month of May approaches, those stoneflies who are mature enough to become adults begin there migrations towards the banks. It's during this time that the stoneflies become very susceptible to fish because they have detached from the rocks and have begun to dead drift downstream. They will continue to migrate downstream until they have made it to a point where they can attach to bedrock only a few feet off the shoreline. Now it is a waiting game for the stonefly.
There are several factors that drive the emergence of the stonefly from the river, but the most important factor is water temperature. Once the water has reached that magical temperature, stonefly nymphs will begin to crawl out of the stream onto streamside brush and rocks. Once the stonefly has emerged from the river it will begin a transformation event from an immature nymph to a mature adult. This event is referred to as 'shucking' and is depicted here on the right.
Once the adult has completely shucked its nymphal layer, it will take refuge in the streamside bushes to dry it's body and wings, which can be a one or two day event. This is why salmonflies require warm, dry weather. When the adults have dried, they begin what I imagine is they're favorite part of their life cycle, mating. The salmonflies remain on the streamside bushes during this event and are often seen with the smaller sized male on top of the much larger female. The sized difference between genders is thought to be an effect of natural selection within the species, which allows the female to carry more eggs. When the female's eggs have been fertilized, she will leave her post on the streamside and begin a migratory flight upstream. The migratory flights range from 1-6 miles upstream and this is why the hatch progresses upstream up to 10 miles a day. Once the female has migrated far enough upstream, she will land on the water and deposit her egg sac into the stream in a fluttering motion. This event marks the end and the beginning of the Pteronarcys Californica's life cycle.
Techniques: During the nymphal migrations at the end of April throughout the month of May, standard nymphing techniques throughout the heavy runs and riffles and into the tail outs is the way to go. Popular patterns include: RL stones, H's rock n' rollers (shown here), thurminators, girdle bugs, and Pats RLs. Make sure that these are fished right on the bottom. If you aren't losing flies, you aren't fishing right.
After the migrations, fishing bigger patterns in the troughs off the banks will treat you right. These patterns include: yuk bugs, jimmy legs, Pats RL, BH buggers, and bitch creeks.
Once the stoneflies have emerged and shucked into their adult forms, there are patterns types to choose from ranging between fluttering stones or low profile patterns. The fluttering stones work well for imitating egg laying females, where low-pro patterns imitate dead stones or males that have fallen in the water. Larger, bushier patterns like fluttering stones, Wike's Big R bug (shown to the left), and terrenastys work well for imitating fluttering salmonflieson the water. Smaller, trimmed patterns like cat pukes (shown below), rogues, chernobyls, widow makers, and carnage stones work well for imitating dead or fallen stones.
Another techniques that is becoming more and more popular is fishing drowned stones. Popular patterns for this technique include: trimmed cat pukes, sunken rogues, drowned stones, and sunken king kongs.
For more information stop in or call the shop.