Guide to Fly Fishing the Gallatin River

Description and Access

For most of its length of interest to anglers, the Gallatin is easy to access off of US Highway 191. The headwaters can be accessed via trail, and the remainder of the Yellowstone National Park section is easy to read as it flows in looping bends through primarily meadow terrain, with some trees. Outside the Park there is a large amount of private land, including places where landowners have erected tall, nasty fences up to the edges of public bridges in order to keep their (often nonexistent) "cattle" from straying. If there's a fence along the road, don't climb it. If it's at a public road bridge, you are within your rights under Montana's stream access law to climb the fence at the bridge right of way in order to access the water. Just be sure to stay below the high water mark. If not, you will be trespassing. Please note that most of the Gallatin cannot be legally fished from a boat, though if you want whitewater thrills and plan only to use the boat for transportation, it's legal to do so. You should only float the canyon portion of the Gallatin if you are an experienced whitewater paddler, as some stretches reach class IV-V.

The Gallatin can be divided into three sections for fishing purposes, though if you want more detail on the Park stretch please check Richard Parks' Fishing Yellowstone National Park, as the Park reach does change a bit as you gain elevation and the river gets smaller. Most of the time the fishing is better in the upper two sections, from the headwaters to Big Sky and from Big Sky downstream to Gallatin Gateway.

The first section of the Gallatin is generally flatter than the second, canyon portion. The character here is riffle-pool, with mostly meadow terrain punctuated by small patches of forest. Numerous bends, undercuts, and the like offer good holding water. This country is somewhat wetter than the other meadow streams in the area, due to its location on the west side of the Gallatin Range, where snow stacks up, so there are more willows than there is sagebrush. This section typically runs clear above tributary the Taylor Fork, except during the height of the spring melt. Unfortunately, the Taylor Fork runs muddy after rainstorms and during the spring melt.

The second section of the Gallatin is much steeper, with boulders the primary structure. This section of the river served as a stand-in for the Blackfoot during the filming of A River Runs Through It. As in the film, stoneflies are the primary insect here. Be careful wading this water, as it is fast and quite deep. Also note the large number of commercial and recreational whitewater rafts and kayaks that use this water. Try to time your visit and fishing spot to stay away from these boats.

Below the canyon, the Gallatin flattens considerably and numbers of browns increase. Some of these fish are quite large. Unfortunately, this section of the Gallatin gets hit hard by summer irrigation drawdowns, an even bigger concern given the river's relatively low elevation. Most summers the elevation and drawdowns mean there will be several weeks in August and September when the river exceeds 70 degrees, and often sections of it will run almost dry. Best to leave this section alone except during the fall brown trout run. Access to this section is also more difficult than it is above.

A special note on winter fishing the Gallatin: beware the twisty, icy US 191. Many people die on this road, which is heavily traveled and narrow. It's terrible in the winter, as the narrow canyon is in shade and there's always some black ice, even with the plows out.


Fish Species Abundance
Cutthroat Abundant in Yellowstone Park, becoming less common and gradually disappearing as you head downstream. Some westslope cutthroat genetics in population, but largely a mishmash of Yellowstone and westslope cutthroats.
Cutthroat-Rainbow Hybrid Abundant in Yellowstone Park, common to rare as you head downriver
Rainbow Abundant except in extreme headwaters.
Brown Abundant except in extreme headwaters.
Whitefish Abundant except in extreme headwaters
Carp Abundant in lower river, just above Three Forks.

The Gallatin fishes as its character suggests. In the Yellowstone Park water and down to Big Sky, matching the hatch or fishing hoppers, beetles, ants, and Spruce Moths during terrestrial time are your best bets. Attractor dry flies will bring fish in the riffles, and nymphs like Princes, Pheasant Tails, and Copper Johns are always good choices. In the heavier flows downstream, stonefly and larger attractor nymphs should be your first choices except during midsummer, when an attractor dry fly or foam hopper trailing a smaller attractor nymph is also a good choice. The Salmonfly and Golden Stone Hatches typically take place around the 4th of July, about the same time as they do on the Yellowstone or maybe 3-7 days later, depending on snowmelt. On the lower river, more limited fish densities and a greater percentage of browns mean my first choice is going to be a streamer except in the depths of winter, when I'll go to a midge larva pattern behind a small Shimmer Nymph, while hoping for Blue Winged Olives.

Always remember your Spruce Moth patterns when fishing the Gallatin in the canyon or upstream. The mountains here are heavily wooded with evergreens, and the last few years have seen extreme numbers of Spruce Moths. With the possible exceptions of upper Soda Butte Creek and the Gardner in Sheepeater Canyon, the Gallatin is the stream where Spruce Moths are most important. Look for them from mid-July onward.

Quality of Fishing By Period: X=high, x=moderate, x?= variable, blank=poor or closed
  May 6/1 6/15 7/1 7/15 8/1 8/15 9/1 9/15 10/1 10/15 Nov.
Upper (Park)     x? x? X X X X x? x?    
  Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec.
Upper (Park to Big Sky)   x? x? X x?   X X X X x?  
Canyon   x? x? X x?   X X X X X  
Lower   x? x? X x?   x?   X X X  


Gallatin River Hatch Charts and Fly Pattern Recommendations
  Timeframe: X=major importance, x=minor importance, blank=unimportant
Insects Jan Feb Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec.
Spring BWO   x x X x              
Fall BWO (Gray Baetis)             x x X X X X
PMD             X X        
Green Drake             X x x      
Gray Drake             x x x      
Tan Caddis (Hydropsyche)             X x        
Caddis, Other       x X   x x        
Yellow Sally Stone             X x        
Salmonfly           x X          
Golden Stonefly           x X x        
Midges X X X x x         x X X
Terrestrial Spruce Moths             X X x      
Terrestrials, Other             X X X x    
Other Trout Foods Jan Feb Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec.
Attractor Dries   x x x x   X X X x    
Attractor Nymphs x x X X X X X X X X X x
Stonefly Nymphs x x X X X X X x x X X x
Streamers     X X X x x x x X X  

Gallatin River Top Flies
Korn's Spruce Moth, #14
MFC Para Spruce Moth, #14
Wood Grain GFA, #10-12
BH Pheasant Tail, #16-18
PFS Beetle, #18
Matt's Golden Stone, #8-12
Matt's Black Stone, #4-8
Coachman Clacka Caddis, #12-16
BH Prince, #10-16
Purple Haze, #12-18

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