Standing atop Idaho’s lodgepole forest-clad Box Canyon, my high school fishing buddy and I watched hundreds of salmonflies clumsily crisscrossing the sky above the Henry’s Fork. We had just had our butts handed to us all morning. We were unable to hook a single trout over fifteen inches. While stowing our gear, a dust laden Bronco pulled down the Targhee Forest service road and parked alongside our underclassed VW beetle. We greeted the angler as he exited his truck and pulled on his Seal Dry latex waders and prepped his flyrod. He introduced himself as Will Godfrey, a local Island Park fly shop owner.
We opted to watch our new, self-assured, angler acquaintance from the comfort of the basalt cliff. Fully expecting to revel in some ‘hot shot’ angler’s misfortune to validate our own poor showing as simply a tough day. It was immediate and it was mesmerizing. He laid out an aggressive, long tight loop against the heavy seams of each midstream broken boulder, each the size of our car, tipped with a single, bulky Sofa Pillow dry. By his third boulder he went tight on a five-pound rainbow, porposing upstream in a rhythmic series of violent leaps and crashes before succumbing to Godfrey’s side pressure and subsequent release.
That was forty years ago. We were two out-of-state teenagers stunned, and schooled, unknowingly by one of the great Rocky Mountain anglers of our youth. But even more consequential, we witnessed the magic of the famed salmonfly hatch in the otherworldly setting of the Henry’s Fork. It was my personal baptism into the giant salmonfly world of Pteronarcys Califronica. This prehistoric and annual migration has since shaped vacations, retirement dates and family relationships.
It has become the ember of countless western river pilgrimages to photograph the modern-day, aquatic insect equivalent, of the great plains migrations of bison in the 1800’s. The similarity with bison migrations of yesteryear doesn’t end with the vast swarms of bugs that fill the sky each spring. Salmonflies, as were bison, are one of the seminal health indicators in our western ecosystems. Stoneflies can only thrive in pure, clear, flowing rivers and streams.
The advent of spring and pending salmonfly emergence is not only celebrated by the appearance of discarded shucks, but also the appearance of fanatic Idaho anglers like Mark Crapo, aka Von Beardly, searching under bridges for creepy crawlers and massive tank size trout with rod and camera in tow. 
A river-by-river diary full of detailed salmonfly hatch progressions from year to year forms the basis of my passion for chasing the big bugs. But the theory evaporates into reality when salmonflies invade your hair, hat strap, behind your ears, under you shirt and yes, even impair your vision. Creepy, invasive and totally awesome at every level!
No joke! Randy Francis retorted that he had another of his successful dry, salmonfly patterns for me. So he revealed a bug vault full of ‘ready to eat’ dry flies for any condition. His offering was matched by two more cases of stonefly nymphs to ensure he was never short-handed on the South Fork of the Snake River. My envy was real as I secretly hoped he would offer a dozen or so to take home. Didn’t happen. 
Salmonflies can hatch as early as May and as late as July on major western rivers. The Yellowstone River provides one of the great mid-summer hatches of salmonfiles, bringing up colorfully adorned native cutts, as Kelli Dotson shows here with her net solidly filled.
Like finding lost gold, it’s hard to beat seeing a silvery, lower river Henry’s Fork brown actively hunting for the emerging and mating salmonflies along the undersides of volcanic, basalt rock cliffs. For big fish, it pays to get out of the boat and stalk the one. 
A male western tanager searches streamside alders for the bug feast of salmonflies. What may surprise many is that birds and trout are also joined by snakes, rodents, otters and even bears to sample on these high protein snacks of spring.
An entire age class of salmonflies, or generations for that matter, can simply disappear due to a single, tragic sediment event. Or they can weaken from a perpetual warming stream flow aided by reckless degradation of riparian habitat or careless toxic releases into our tributaries. Our individual and collective efforts, aided by the support of noble frontline, science-based conservation organizations like the Henry’s Fork Foundation and Trout Unlimited, can continue to enhance, protect and preserve our waterways to the benefit of anglers and mankind. But also ensuring that the otherworldly, annual salmonfly migrations of the American West live on forever.
– Robert Dotson
Salmonflies are most active during (and between) dusk and dawn when it comes to their emergence from the river depths. But it is hard for the dry fly angler to beat a warm spring day fading into evening, with an ever so slight breeze to get trout actively looking up. These are the times that drive me to search for the largest fish in the river. Trout that only show themselves when their major food source is available during daylight hours.
Salmonflies, as were bison, are one of the seminal health indicators in our western ecosystems.
Contributed By
Robert Dotson
Robert Dotson left the Seattle tech world ten years ago and was reunited with his Scott rod, Nikon and a Pelican case. Together with his wife Kelli, they hunt the kiwi backcountry, ocean flats and remote river bottoms. But always return to their first love – the back roads of the Rocky Mountains. His art is frequently found in fly shops, lodges and conservation fundraisers with work appearing in The FlyFish Journal, The Drake, FlyLife, Tail, Jackson Hole Mag and his earliest work in…Catch Magazine.
