In the heart of the aquatic insect world, there are one species that stands out above the rest due to its massive size and intimidating appearance. Its full name is Pteronarcys californica, but as anglers, we simply refer to it as the Salmonfly.
In the early Spring of 2020 Phil Tuttle, Chris Cutler, and I began planning a trip around the upcoming salmonfly hatch. For weeks we anticipated not only catching fish on large dry flies, but as filmmakers we also hoped for the opportunity to film their emergence; the exact moment when the adult salmonfly breaks free from its exoskeleton as a winged adult ready to take its first flight. Finding the leading edge of the hatch was our goal, and after driving 400 miles to fish this hatch for only two days our fingers were crossed that we would be able to find both fast fishing action, and emerging salmonflies to film.
It’s important to note that as with all other river-dwelling insects that emerge, the hatch begins in the lower stretches of the river and progresses upstream over a period of weeks as temperatures in the river system increase. In other words, if you’re off by a mile you could miss the hatch completely. Here are a few other interesting life-history characteristics of salmonflies that are good to keep in mind when planning a trip to fish a salmonfly hatch.
Salmonfly Life-History
Salmonfly Nymphs:
Salmonfly nymphs live the majority of their lives on the stream bottom. Here they make a living by wandering around scraping and consuming detritus from the riverbed, growing ever larger with each year that passes. They remain as nymphs in this underwater state for up to four years before it’s time for them to advance into adulthood.
Salmonfly Emergence:
Every year in the late spring to early summer these nymphs experience a change which prompts them to migrate to the edge of the riverbank in preparation for emergence. Typically, in the late afternoon salmonfly nymphs crawl out of the river and anchor themselves to nearby rocks, trees, or any other solid surface where they then proceed to emerge. This is when they leave behind their aquatic life for good.
Adult Salmonfly:
Now, in their terrestrial form salmonflies have one main item on their agenda, and that’s to reproduce. After reproduction has occurred the egg-ladened females return to the water’s surface to deposit their eggs. Both males and females are clumsy fliers and are oftentimes knocked or blown onto the water’s surface. Hungry trout await the opportunity to gorge themselves on the less fortunate salmonflies that end up drifting helplessly on the water’s surface. As anglers, this is where we come into the picture. Tossing extra large dry flies to eager trout, that for the time being have lost all fear of surrounding threats.
During the first day of our trip there were adult salmonflies lining the foliage up and down the river. Just the sight we were hoping to find, giant bugs EVERYWHERE! However, we were finding the occasional engorged fish willing to eat our dry flies, but the action was a bit slow and it felt like we were at least a few days, and a few miles behind the hatch on this stretch of river. As the night drew to an end we still hadn’t found the leading edge where the salmonflies were currently metamorphosing into adults. We knew we were close, but with the clock ticking on our trip, we needed to find it fast if we were going to film their emergence.
The next morning we decided to relocate miles upstream from where we were the day before. As we systematically worked our way upstream not only searching for fish, but also checking every shadow on the backside of each large boulder for the signs of emerging salmonflies, it began to feel hopeless as the hours passed by. Mile after mile we continued fishing and hoping, but as the afternoon began to fade we knew our opportunity was slipping by.
But in reality we really didn’t have anything to complain about. We had been finding quality fish that were more and more willing to eat our dry flies the further we worked upstream, and the scenery was second to none. But the hopes of filming emerging salmonflies was looking more and more bleak as we neared the end of our final day. Although we didn’t have the crowning shots we were hoping for, we still had enough good footage to tell a compelling story of these amazing insects and the hatch event that they bring to pass each year. Before our trip was even over, we were already planning for next year when we’d once again try to find and film their emergence.
However, as the afternoon was fading and our time was nearly up, we noticed on the backside of a decent size boulder half in, half out of the water, a clustered up emerging frenzy with dozens of salmonflies working their way into adulthood. We couldn’t believe it! There were salmonflies in all stages of the hatch, nymphs crawling out of the water, others slowly protruding from their exoskeletons, and still others drying their new wings before taking their first flight. With so little time left we had found what we had been hoping for. We quickly grabbed our cameras and began recording.
The evening ended without casting another fly. We found what we had come for, both the fish and the insects had complied with our desires and the river had left us with nothing more to desire. Watch the full film below:
