Montana’s Salmonfly Hatch

One of the most anticipated events for anglers in Montana, the annual salmonfly hatch, is here. It's time to grab your dry flies and hit the river for a chance at a super-sized trout.

Montana’s Salmonfly Hatch

Anglers searching for big trout, get your dry flies ready—it’s salmonfly hatch season in Montana. The large insects, some up to three inches in length, crawl from the river bottom and head to the water’s surface—luring larger, deep water-dwelling trout up from the deep as they risk it all for the ultimate protein-packed meal. The colossal hatch, in both size and number, creates a truly one-of-a-kind fly fishing experience. The hatch begins as early as late-May on the Fire Hole River in Yellowstone National Park and continues for about six weeks, through early July on stretches of the Yellowstone River between Livingston and Gardiner.


The salmonfly hatch is one of the best times to fish on one of Montana’s many stone fly-laden rivers including the Big Hole, Clark Fork, Madison, Yellowstone, Smith, Gallatin, and Jefferson Rivers. Rock Creek near Missoula is legendary for its world-class salmonfly hatch, but many of Montana’s smaller rivers and creeks are also great places to fish trout during the salmonfly hatch. Often overshadowed by the more publicized spots, casting on smaller rivers and streams means less fishing pressure and trout that haven’t gotten wise to imitations yet—during the salmonfly hatch, riverfront property becomes invaluable. If you’re not one of the lucky Montana landowners with waterfront property, check with a guide at the closest fly shop for insights on smaller rivers and streams that are worth a wade.

Close up of a salmonfly, photo courtesy of Brian Grossenbacher.


The salmonfly is one of the best hatches to fish in Montana thanks to the size of the hatch, the size of the insects, and the size of the trout they bring to the surface. Of course, experienced anglers know there is no guarantee that you’ll catch a 28”+ trout during the hatch, but you might. The potential to catch a trophy-sized trout with a dry fly draws anglers from around the country—lots of them. If you’re booking a guide it’s best to do it well in advance before guides book up. Consider fishing harder-to-access locations with faster-moving water for less fishing pressure as well. Trout often get wise when they have experienced a large number of imitation flies during the hatch and might start to ignore your dries. 

Timing is everything for the salmonfly hatch. Although quite predictable, the hatch dates vary slightly from year to year and by stretch of river. Riverflow, water temperature, and time of day also come into play when calculating your odds. Some anglers like dragging heavier nymph flies a few days before the hatch and some wait until a few days after the trout have eaten their share of the real thing, slapping their imitation flies when the hatch is over and the fish start to feel hungry again. Trout often eat so many salmonflies they need several days to metabolize the protein and for hunger to return. The hatch usually moves upstream, so it’s possible to get ahead of it, smack in the middle of it, or behind it, depending on your strategy and preferred location. The hatch usually moves by a couple of miles a day but can vary based on climate conditions.  

Fishing Secret Creek, photo courtesy of Brian Grossenbacher.


Trout often gather near vegetation along the shore—waiting for clumsy salmonflies to fall into the water as they climb out to molt. Setting up downstream from overhanging bushes or branches often proves fruitful, especially in higher and faster-moving waters. As the summer progresses and runoff diminishes, salmonflies can hatch further from riverbanks as flows slow down and water levels drop. When it comes to flies, the larger the better—consider deer hair or foam flies in sizes 2-8, with an orange area similar to the underside of the salmon fly. Sizeable and aggressive trout often jump to the surface when they see a flash of orange thinking it’s the orange-colored bellies of a salmonfly. Late in the season, some anglers switch to golden stone flies, or a hybrid between the two as the trout begin diverting from the orange flies after too many disappointments.

Looking for more details on fishing the famed salmonfly hatch in Montana? Contact one of the featured fly shops below for hatch reports and location recommendations:

Brown Trout, photo courtesy of Brian Grossenbacher.

Good luck to all our angler friends who are hoping to catch the big one this summer. Want a front row seat to the hatch on your own Montana ranch? Contact us for more information on available riverfront properties:


The information contained herein was obtained from sources deemed to be reliable. Western Ranch Brokers makes no warranties or guarantees as to the completeness or accuracy thereof.
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