Journalist, avid fisherman, and friend Greg Thomas gives his local insights on spring fishing in the Big Sky State.
“If I had to choose one time of the year to fish Montana, I’d likely forgo summer “prime time” and choose, instead, the spring “shoulder” season, meaning the months of March, April, and May.” - Greg Thomas.
Spring fishing in the Big Sky State. Photo courtesy of Greg Thomas
I realize that goes against the grain, because most anglers believe the “real” season begins on the Fourth of July and ends when the kids return to school around Labor Day. However, that mindset could prevent anglers from hitting some of the best hatches and the most productive dry-fly fishing of the year, a time when March brown drake and blue-wing olive mayflies, plus the meaty skwala stonefly, emerge from the bottom rocks in masses. That brings wild rainbow, brown, and cutthroat trout to the surface in droves. In addition, after surviving all winter on minuscule midges, large trout (meaning fish between 17 and 20-some inches long) are eager to chase streamers—which imitate minnows and sculpins—as they replenish fat reserves lost during the late fall and winter seasons.
This all occurs during Big Sky Country’s season of rebirth, as ice and snow melt and the rivers run mostly lowish and clear, which means prime conditions for fishing dry flies. Later in spring, as the first heatwaves hit the high country, snow melts quickly and the rivers swell and turn brown, carrying sediment, micro-debris, and, sometimes, entire trees downriver in a torrent. At that time, trout can be difficult to tempt, and wading or floating a river can be, at worst, life-threatening. But, “pre-runoff” conditions are often ideal. When they are not anglers, they simply have to wait a day or so before the rivers slide back into shape.
Photo courtesy of Greg Thomas
You won’t see this pre-runoff timeframe advertised in the many tourism brochures because, well, to be honest, it’s not for everyone.
On any given spring day, conditions could range from sunny and 75 degrees to low scudded clouds offering rain, sleeting, and snow. That’s the wildcard in spring fishing. But those who roll the dice get shots at large, hungry trout that haven’t seen a dry fly floating over their heads since Thanksgiving. When you hit it right—and you do hit it right more often than not—the fishing can be spectacular.
The skwala hatch isn’t restricted to Montana—these bugs are ubiquitous on freestone rivers sprinkled across the northern Rockies and Pacific Northwest. You’ll find the hatch on Montana’s Blackfoot, Big Hole, Bitterroot, Jefferson, and Smith rivers, along with Rock Creek, to name a few; also on many streams in Wyoming, Idaho, Washington, and Oregon. In a typical year, skwala stoneflies are on the water by mid-March, and their presence, on some waters, continues well into May. Skwalas are relatively large bugs, matched by size 8 to 12 imitations. Trout, after surviving all winter on those aforementioned tiny midges, are on the lookout for these creatures, which are the largest bug they’ve seen in several months and the largest they’ll find until salmonflies show up in late May or early June.
Springtime in the Rockies Photo courtesy of Greg Thomas
When the bugs first come off, anglers match them with nothing more precise than a high-riding and highly visible Chubby Chernobyl. But this hatch isn’t unknown, and before long, after the fish see a bevy of artificial flies going over their heads, they can get picky. When that happens, anglers may need to fish a more subtle pattern, such as a Water Walker, Rastaman Stone, or a Plan B, all low-riding flies that partially penetrate the surface film. Skwalas are most active in the afternoon hours, typically from noon to 4 or 5 p.m. But remember this: skwalas migrate from the middle of the river to shore, and trout crush them as they struggle to do so. That’s why trout are always on the lookout for a skwala nymph. If you get on the river early, before the air temperature warms and adult skwalas become active, be sure to fish a double nymph rig or a high-riding Chubby with a skwala nymph dangled 14 inches off the back of that fly.
Photo courtesy of Greg Thomas
On shore, skwalas break free of their nymphal shucks and become winged adults, clinging to sticks, branches, logs, rocks, anything they can clasp onto to prevent falling in the water. They’d get fired if they were being paid to do just that—they’re clumsy and lots of adult skwalas fall into the water and struggle downstream where trout are waiting. In the afternoons, adult skwalas start flying, many eventually dapping their fannies on the surface to release eggs. When you see this activity, it makes sense to give some slight twitches to your adult skwala dry, which mimics that egg-laying effort.
Don’t expect to see loads of skwalas in the air or on the water at any given time. Some days, you may see a few. Other times, you may see none. Some days they fall out of the sky and dimple the surface like raindrops. Just know, whether you see those bugs or not, trout are aware of their presence. Know that a skwala on the surface is an easy meal at a time of year when those fish desperately need protein, and it won’t be ignored.
Photo courtesy of Greg Thomas
When targeting the skwala hatch, don’t sleep on the March brown drake. This size 12-to 16 mayfly is a substantial meal and can emerge in masses, often outshining the skwala. You may see that bug on the surface beginning around 10 or 11 a.m., and the daily hatch may not wind down until 5 or 6 p.m. On cool spring days, however, it may only come off in a burst, sometime around midday.
You can get as technical as you like with this hatch, tying on a variety of March brown imitations, but the fish won’t shy away from standard mayfly imitations, such as a Parachute Adams, Purple Haze, Cripple, Sparkle Dun, or Comparadun. When the March browns pop, they litter the surface and trout rise accordingly. Again, this window may only last an hour or two on cool days, but those temperatures can play into your favor. When the air temperature is cool, it takes a while for those bugs’ wings to dry. That means March browns spend more time on the surface than they would on a warm, sunny day, when their wings dry quickly.
Photo courtesy of Greg Thomas
Cool days afford a wider window for trout the trout may lazily slurp down one mayfly after another. This creates one of those rare situations when every fish in the river seems to be feeding at once, and an angler might hook scads of trout in an hour or two. There are no guarantees on the water, but you’re as likely to see that kind of feeding “frenzy” on the March brown as any other hatch of the year. Speaking of other bugs, you might see blue-wing olive mayflies emerging simultaneously with those March browns. No reason to fret: if you see those blue-wings, which range between size 16 and 20, tie on a similar size Parachute Adams or a Sparkle Dun and run it behind your March brown pattern. A double dry-fly rig can be deadly when multiple mayflies emerge at one time, and you don’t know which one the trout prefers that day.
Photo courtesy of Greg Thomas
If you float these rivers during spring, an angler in the front of a boat might cast a March brown imitation followed by a BWO dry, while an angler in the back of the boat could slap down a skwala dry and nymph, or a skwala dry trialed by a March brown dry or nymph. It’s a good way to cover the bases, with the trout seeing those subtle dry flies first, followed by the big stuff shortly after.
While spring fishing in Montana and elsewhere can be fantastic, that’s not the only reason to visit Big Sky Country in March, April, and May. By doing just that you’ll see the first blades of grass poking out of the ground, buds and then bright-green leaves forming on the trees; you’ll witness the return of swallows, meadowlarks, redwing blackbirds, yellow tanagers, and a variety of waterfowl; and if you’re observant you might witness deer, elk, moose, bighorn sheep, antelope, foxes, coyotes and bears welcoming their new ones into the world.
Spring serves as a rebirth for a multitude of creatures. Photo courtesy of Greg Thomas
Spring is the season of rebirth, a great time to be outdoors and on the water in Montana, with a full year of fishing possibilities resting directly ahead. You’ll get your licks in on some of the best hatches of the year, well before the summer rush, an opportunity to head back home after your trip and say to family and friends—who are still reminiscing about last year and are only now dreaming about the summer ahead—“Man, you should have been there in April!”
About Greg Thomas
Greg, courtesy of Greg
Greg Thomas writes for various publications, including The New York Times, Forbes Alaska, Gray’s Sporting Journal, and Outside. His books include Flyfisher’s Guide to Washington and Flyfisher’s Guide to Montana. He is the former managing editor of Big Sky Journal and the former editor-in-chief of American Angler and Fly Rod & Reel magazines. He earned a journalism degree at the University of Montana, then made his rounds through some of the West’s most inviting trout towns, including Jackson, Wyoming, Ketchum and Boise, Idaho, and Ennis, Hamilton, Gallatin Gateway, and Missoula, Montana. He spends considerable time in Alaska each year when not chasing trout around the Rockies, or trout-setting on tarpon in salty environs. He is a former commercial fisherman and college basketball player who trained under legendary Washington state coach Ken Bone. He is an avid upland bird and big game hunter and now lives in Missoula, Montana, with his trusty Labrador retriever, Rye. He spends part of his life telling his two teen daughters, “Do as I say, not as I do,” an effective tactic, only part of the time.
Looking for more detailed information about springtime fishing in Montana? Contact one of the featured fly shops below for hatch reports and location recommendations:
- Grizzly Hackle Fly Shop - Missoula, MT
- The Rivers Edge - Bozeman, MT
- Montana Angler - Bozeman, MT
- Montana Troutfitters - Bozeman, MT
- Yellow Dog Flyfishing - Bozeman, MT
- Yellowstone Angler Fly Shop - Livingston, MT
- Sweetwater Fly Shop - Livingston, MT
- Angler’s West Fly Fishing Outfitters - Emigrant, MT
- Sunrise Fly Shop - Melrose, MT
- Stonefly Outfitters - Twin Bridges, MT
- Frontier Anglers - Dillon, MT
Catch of the day courtesy of Greg Thomas
Want a front row seat to the hatch on your own Montana ranch? Contact us for more information on available riverfront properties.
