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Flathead River Fly Fishing

The Flathead River takes the prize for the state’s most diverse and unique river system. Comprised of the North Fork, Middle Fork, South Fork, and the main stem, which all could be considered their own river, the Flathead begins in British Columbia just above Glacier National Park. The main branch of the Flathead River that flows into Flathead Lake and close by the towns of Whitefish, Columbia Falls, and Kalispell is by far the most pressured section. Therefore, this article will focus on the North, Middle, and South Fork of the Flathead River.

For fly fishing enthusiasts, the North, Middle, and South Fork of the Flathead flow through some of the most pristine and remote areas in the lower 48. Anglers can float these sections in rafts and see minimal signs of human life to extend their trip. In addition to the serenity and seclusion, fly fishers can target unpressured and wild Westslope Cutthroat trout, Montana‘s state fish, using attractor dries. Westslope cutthroat trout are curious fish – bumping flies with their noses, swimming underneath your fly to get a better look, and sometimes smashing it so hard that they miss it entirely.

At Yellow Dog, we frequently receive requests for wilderness float fishing trips for the angler yearning for a complete wilderness experience. They are only gaining in popularity year-over-year as many Americans hanker to remove themselves from the hustle and bustle of everyday life.

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View All Montana Fly Fishing Rivers

Sections of the Flathead River

North Fork of the Flathead River
The North Fork of the Flathead River begins in the Canadian Rockies in British Columbia near Flathead Peak. When it crosses the international border, it then flows south for 58 miles until it meets the Middle Fork of the Flathead River near the town of West Glacier. Between the border and the confluence with the Middle Fork, the river passes through some of the most beautiful country in the Rockies. It passes in-between Glacier National Park to the east and the Flathead National Forest to the west. It is not rare to see eagles, bears, moose, elk, and deer while floating down the river.

Something that the three forks of the Flathead have in common is the wild colors of the water. Within a day, you will float through electric blues, emerald greens, deep navy, and ruby-stained water as you progress downstream. It is comparable to the saltwater of an exotic tropical location in the Caribbean or South Pacific. Stands of pine, fir, and aspen blanket the mountains and provide a fresh aroma.

The North Fork features many gravel bars, shelves, drop-offs, large boulders, runs, pockets, and plenty of seams where cutthroat and some rainbow trout await to smash a dry. The peak amount of flow on the North Fork is in early June during runoff. The water begins to settle by July, and low water is possible by August. This section of the river has some whitewater (Class I-II).

Upper Middle Fork of the Flathead
Only accessible from the air, by foot, or horseback, the Upper Middle Fork is in some of the most remote territories in the lower 48. This part of the river flows through the Great Bear Wilderness area, which comprises over 285,000 acres northwest of Montana’s Bob Marshall Wilderness. The Great Bear land serves as a lobby between the Bob Marshall Wilderness and Glacier National Park, which comprises over three million acres of land. Thanks to relentless conservation efforts, this section of the Flathead that flows through the Great Bear has been designated as a wild river under the National Wild and Scenic River System. As a result, a plethora of cutthroat and rainbow trout, elk, moose, bears, deer, mountain sheep, grouse, eagles, and other mammals call this territory home.

The river can move fast through the Middle Fork. Because it is a freestone river, it doesn’t have the same food sources as a tailwater fishery does. This translates to trout that are opportunistic feeders. With the fast current and minimal food, they will take just about every opportunity to eat! Using foam dry flies or other attractors will entice trout to come from the bottom and wreak havoc on a potential meal.

Middle Fork of the Flathead
A Middle Fork trip is a splendid way to experience a multi-day wilderness float trip with a backdrop of Glacier National Park. Anglers will be able to cast dries all day long into gin-clear water for willing cutthroat trout. The Middle Fork consists of numerous gravel bars, shelves, drop-offs, boulders, and deep holes for trout to hide. In addition, there are a few Class II and III rapids that provide some more excitement to the trip.

South Fork of the Flathead
The South Fork of the Flathead is known in the fly fishing world as the Mecca for dry-fly cutthroat fishing. Located in the 1.5 million-acre Bob Marshall Wilderness, America’s first-ever designated wilderness area, the South Fork is formed from Danaher Creek and Young’s Creek junction. From here, it runs 45 miles due north, fed by dozens of small tributaries, where it exits the wilderness near Spotted Bear Ranger Station. This trip completely transects the wilderness area from south to north, right through the deepest, most remote area of the “Bob.”

Seasons on the Flathead River

The forks of the Flathead River can fish well during early May during pre-runoff. This is an excellent time to target spawning cutthroat that is coming in from Flathead Lake. Around mid-to-late May, the river is experiencing runoff and should be left alone.

This is the best time of the year to fly fish the Flathead River system. The water drops to floatable levels, and the cutthroat trout are hungry. Because this is a freestone river in a remote territory, the river can throw a few curveballs each year. There may be a new side channel, a downed tree that blocks the river, or tricky new water that wasn’t there the year before. It pays to go with an experienced outfitter and guide who knows the area and adequately navigates it.

Popular Flathead River Flies

Dry Flies:

  • Chubby Chernobyl (size 4-14)
  • Royal Wulff (size 8-14)
  • Stimulator Dry Fly (size 8-14)
  • Red/Yellow Humpy (size 8-14)
  • Royal Stimulator (size 8-14)
  • Sweetgrass Hopper (size 8-12)

Making the Most of Your Trip

The Flathead River is one of America’s most iconic and wild trout fisheries. It is surrounded by some of the most untouched and remote territories left in our country. Before or after your trip, be sure to check out a few of these places. You made it all the way out to Northwest Montana, so why not?

  1. Glacier National Park- This goes without saying, but everyone should take a drive or hike through this beautiful country at least once in their lives. A drive up “Going to the Sun Road” is a bucket list item you should cross off. To avoid traffic, get there for a sunrise or sunset drive.
  2. Whitefish, MT- Whitefish is similar to Bozeman, Montana, and has a similar appeal to Jackson Hole, Wyoming. It is a funky ski town with numerous shops, bars, breweries, and great restaurants.
  3. Flathead Lake – Flathead Lake is the largest natural freshwater lake in the western United States. It hosts spectacular views, nearby recreation opportunities, and numerous places to eat.
  4. Hiking – There are many hikes in the area that will ultimately take your breath away, sometimes in more ways than one. Check out Hidden Lake, Ptarmigan Tunnel, or Apgar Lookout Trail near the town of West Glacier.

Lodging Options

Glacier Anglershas been family-owned and operated for 40 years and is considered Montana’s longest-running river outfitter. With over 500,000 guests taken safely down the river since 1976, they are proud to have the best safety record in Glacier Country. Montana is legendary for its outstanding fly fishing, and the waters fished by Glacier Anglers are no exception. Glacier Anglers offers day trips, overnight float trips on the North and Middle Forks of the Flathead River, and multi-day backcountry trips into the Great Bear Wilderness to fish the acclaimed Upper Middle Fork Flathead River. These waters are all home to native Westslope cutthroat trout and rainbow trout.

Flathead River Fly Fishing .
Flathead River Fly Fishing .
Flathead River Fly Fishing .
Flathead River Fly Fishing

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