Gallatin River Fly Fishing in May

Gallatin River Fly Fishing in May

In May, the Gallatin River gradually builds from spring thaw to peak runoff. Snowmelt swells the river and degrades clarity. Fishing can be good during the earlier weeks of the month, but there's a countdown to June when the river becomes inhospitable for a few weeks.

Trout feed aggressively near banks and mid-river structures, but wading gets harder as flows rise.

Gallatin River Fly Fishing Hatches in May

Blue-winged olives (BWOs), march browns, and midges emerge in early May. Caddis become increasingly active in the Gallatin Valley sections and can provide some terrific dry fly fishing in the evenings when water levels are stable.

Bozeman Fly Fishing Guide Pro-Tip:

The river can be dirty this time of year, but there are still good angling opportunities if you go above Taylor's Fork Creek near Big Sky, MT. The Gallatin River is normally clearer above this creek as it is the main source of sedimentary runoff. When flows are high, use a nymph and indicator setup with a size 10, brown Pat's Rubberlegs and a size 10 red Sparkle Worm along the banks.

Gallatin River Fly Fishing Techniques in May

Stay on shore or wade carefully, and focus on slow moving water near the banks or next to structure. Nymphing tends to catch the most fish. Use short casts with heavily weighted rigs to find some large brown trout as water levels rise and clarity starts to diminish.

Streamer anglers can dredge heavy sink tips through holding lies as the river rises.

Dry fly-fishing opportunities abound in the early part of May if water levels and clarity remain stable.

Gallatin River Fly Box for May