Top 4 Hatches For Fly Fishing in Bozeman

Chasing hatches usually doesn’t work out. Insects don’t own, or follow, calendars. The key to a great flyfishing trip is enjoying the conditions you fish instead of trying to fish the conditions you enjoy. That said, if you roughly time your fishing windows around optimal insect activity, you might hit one of those magic days when the surface seems to boil with bugs and just about every trout in the river comes up for them.

Here are my four favorite hatches to fly fish on Bozeman area rivers. I’ve listed these in chronological, not hierarchical, order, because any one of them can give you a lifetime day of fishing if you hit it right.

1) Mother’s Day Caddis

Somewhere in the first two weeks of May, millions of Grannom caddis simultaneously get the message that it’s time to party, and party they do. During this hatch’s peak, live caddis create a writhing skin across the river’s surface. It can get so thick that fish won’t notice your flies amid the galaxy of naturals. That’s a good problem to have, and can be solved by using flies a size or two larger than the naturals and making precise casts.

This hatch fishes especially well on the Yellowstone River, where it is both famous and famously fickle. River conditions prevent anglers from effectively fishing it every 2^nd or 3^rd year. If runoff starts early, the Yellowstone is often “blown out,” or carrying too much sediment for fish to see the bugs. If runoff comes late, or we get a cold snap in early May, strap in.

The lower Madison also gets an excellent Mother’s Day hatch, usually a week or two earlier than the Yellowstone. Because it’s a tailwater, the Madison’s less affected by runoff. The caddis hatch on the Lower isn’t quite as impressive as the Yellowstone but still worth getting excited over.

2) Golden Stoneflies

Salmonflies get the glory, but golden stones get the fish. If you happen to hit a river on exactly the right day when the salmonflies are out and the fish are looking for them, you should probably buy a lottery ticket on the way home, because your luck is running. The vast majority of the time, however, chasing salmonflies means seeing far more boats than trout in a given day.

Golden stones, on the other hand, are under-rated in my opinion. Close relatives of the famed salmonflies, goldens are just a little smaller and emerge just a little later. If you enjoy fishing salmonflies, have always dreamed of experiencing a salmonfly hatch, or have been disappointed by salmonflies in the past, consider focusing on golden stones instead.

Here’s why: 1) They usually hatch after salmonflies, so you can avoid the flotillas that chase the biggest big bugs. 2) Trout can only eat so many salmonflies before they get completely gorged, and then they stop feeding for a few days. Once they’ve digested that massive meal, they continue looking skyward and will gladly come up and munch a well presented golden stone. 3) I think trout actually prefer golden stones. I’ve been on the water when both bugs were hatching simultaneously, and on those days, we’ve always caught more fish on golden stones than salmonflies.

3) Pale Morning Duns

If there’s one hatch you can almost count it, it’s the pale morning dun, or PMD. These reddish yellow mayflies hatch consistently on most Bozeman area rivers between early-June and early August, depending on the river.

Unlike the Mother’s Day caddis and stonefly blitzes that appear and disappear in a blink, PMDs hatch slowly and steadily. These mayflies will continue to come out when the weather is good over several weeks.

PMDs are fair weather flyers, hatching best on warm, sunny, early summer days—no need to suffer frozen fingers, torrential rain, or scorching heat. That said, they can be patchy from day to day and stretch to stretch. You might find one section where the fish are gobbling PMDs and then not catch another fish on that bug all day long. The most consistent PMD hatches happen on the Paradise Valley spring creeks, where you’re just about guaranteed to find fish rising for them in July and early August.

4) Tricos

Tricos are polarizing. People generally love them or loathe them, but since the trout like them, I’m a fan. The downside of tricos is their size, or lack thereof. To effectively imitate these diminutive mayflies, you’ll often have to fish a size 20, though sometimes you can get away with an 18.

The upside is that they hatch late in the season, August and September, when almost all the other insects are finished. From dawn until mid-morning you can find good numbers of fish hunting these small mayfly spinners in back eddies and slow seams. I don’t know what it is about tricos, but despite their tiny size, they attract bigger fish. It’s not uncommon to catch browns over 18 inches on size 20 trico dries. It’s challenging, but incredibly rewarding.

Final Thoughts

Part of what makes Bozeman fly fishing so exceptional is the variety of hatches on our rivers throughout the season. I didn’t even mention blue-winged olives, drakes, yellow sallies, or spruce moths, but when forced to pick a handful of favorites, these are 4 of my top choices.

If I were planning a fly fishing trip to Bozeman, I’d consider building my itinerary around one of those potential hatches. The guides at Fins and Feathers will be more than happy to help you maximize your chances at success targeting any one of these emergences. Remember, however, that hatch chasing is finicky business. Plan your trip as best you can, but remain open to whatever the river gives you.

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