Fly Fishing Gardner River - Gardiner

Overview

The Gardner River’s lower Montana reach descends through a rocky canyon to the Yellowstone River at Gardiner. Sagebrush and juniper frame boulder gardens, plunge pools and short runs beneath Mammoth Hot Springs. Rainbow, brown and cutthroat trout inhabit the pockets and sheltered seams, with mountain whitefish in deeper water.

Reading the Pocket Water

Look for the softer current behind a boulder or the edge of a plunge-pool tailout. A short nymph drift can reach a sheltered lie without sweeping across the faster channel. Adjust weight and depth between pockets, and study each pool before extending the cast.

Brown trout move into the Gardner from the Yellowstone in fall. Deeper pools and tailouts offer streamer presentations, while stonefly nymphs can cover the subsurface seams. The canyon’s varied current calls for attention to individual holding water rather than repeated casts through the fastest runs.

Seasonal Flies

Salmonflies and golden stones provide early-summer options, followed by yellow sallies, caddis and pale morning duns. Hoppers, ants and beetles offer bankside choices from late summer into fall, and blue-winged olives add small-fly opportunities on overcast days. Midges and smaller nymphs are other options when fish feed in slower pools.

A dry-dropper can cover a short pocket or tailout, with the dropper depth adjusted to the chosen lie. Hot-spring water enters upstream and influences this reach, giving it a different temperature pattern from colder mountain tributaries. Observe the water and feeding behavior rather than assuming the same presentation will suit every visit.