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 Bighorn River

Description: A ribbon of green slicing through parched land, the Bighorn rushes past scenic bluffs and thick cottonwood bottoms, providing anglers some of Montana's best trout fishing.

Vital statistics: 84 miles long from Yellowtail Dam to its juncture with the Yellowstone near Custer.

Level of difficulty: A Class I river, suitable for practiced beginners.

Flow: Annual mean flow: 3,482 cfs near St. Xavier. Dam-controlled, floatable all year. Can have excellent conditions in May and June when other rivers are high with runoff. Optimal flows for fishing are 3,500-4,000 cfs.

Hazards: Snags and occasional logjams, swift flows in the upper section. Sudden high winds associated with storms. Three diversion dams (portage necessary).

Where the crowd goes: Afterbay to Bighorn.

Avoiding the scene: Downstream from Hardin.

Inside tip: Good fishing on warm winter days and in early spring. One of Montana's warmest areas.

Maps: BLM: #79 (Hysham), #80 (Hardin), #81 (Lodge Grass)
USGS: Billings-MT, Hardin-MT, Forsyth-MT
Montana Afloat: #14, The Bighorn River

River rules: No motorboats from Afterbay to Bighorn. A National Park Service $5-per-vehicle user fee or $30 annual fee is required for floating between Afterbay and Bighorn. Permits can be purchased at Quill Gordon Fly Fishers and near the NPS Afterbay access.

For more information: Bighorn Trout Shop, Fort Smith; Bighorn Angler, Fort Smith; Quill Gordon Fly Fishers, Fort Smith; FWP, Billings; National Park Service, Fort Smith.

The paddling: Steeped in history and shrouded in controversy, the magnificent Bighorn River springs from the glaciers of the Wind River Range in western Wyoming. It may be the very best river in the United States for trout fishing. With tributaries including the Wind, Shoshone, and Little Bighorn Rivers, this is a big river, nearly as large as the Yellowstone when the two merge near Custer.

As the Bighorn flows from Wyoming into Montana, it carves a rugged and scenic canyon that extends for nearly 50 miles. This great chasm winds and twists through the mountains in a tortuous course, its limestone and sandstone cliffs exuding the same brilliant colors and hues as the Grand Canyon of the Yellowstone in Yellowstone Park.

According to a 1932 newspaper account, the Bighorn Canyon once contained formidable rapids: "This river is one of the most dangerous in America to traverse. Many have lost their lives in attempts to go down the rapids, while a few others succeeded in accomplishing the feat." Famous mountain man Jim Bridger claimed he shot the Bighorn Canyon on a raft made of driftwood logs. Bridger, however, was known to stretch the truth. He also said the rivers in Yellowstone Park steamed because they flowed so fast they got the river bottom hot.

Yellowtail Dam transformed the treacherous Bighorn Canyon into a flatwater paddle. The 525-foot-high dam, completed in 1967, backs up 71 miles of river. While a canoe paddle through the canyon remains extremely scenic, the area is used primarily by powerboaters and water-skiers.

Jim Bridger was only one of the dozens of mountain men who trudged up the Bighorn on their way to outstanding fur-producing areas along the Wind and Green rivers. This river valley is alive with Montana history. While Lewis and Clark did not explore the Bighorn, it's obvious from Captain Clark's journals that the Corps of Discovery knew the approximate length of the Bighorn and some of its tributaries. The river was named for its healthy population of bighorn sheep in the canyon area.

In 1807, an enterprising Spaniard named Manuel Lisa constructed Montana's first trading post at a point near where the Bighorn and Yellowstone rivers join. In future years, this spot became the site of several other forts, a projected city, and an army headquarters. All are gone today. Near Yellowtail Dam, the remains of Fort C. F. Smith can still be viewed. It was built in 1866 to protect travelers using the Bozeman Trail. The trail crossed the river about three miles below the present site of Yellowtail Dam.

Construction of Yellowtail Dam changed the entire character of the Bighorn River in Montana. The river once carried a heavy silt load to the Yellowstone. Now, the dam traps the dirt. Below the dam, the Bighorn winds through arid benchlands and thick cottonwood groves. The river is an oasis in the middle of a parched land, a belt of green that attracts many species of wildlife, including deer, beaver, and songbirds. During migration, waterfowl flock to the Bighorn.

The combination of less sediment and regular flows means the river no longer braids or creates islands. In fact, about 1,500 acres of islands have disappeared since 1967, a 50 percent decrease. While this habitat loss is especially significant to beaver, muskrats, and geese, other native wildlife associated with the river have also suffered.

On the other hand, the combination of less sediment and cold flows from the reservoir has created an outstanding trout fishery. The river is not only rich in vegetation, but it squirms with aquatic life, including freshwater shrimp and caddis fly larvae. The river flows through limestone country, and the water is quite mineralized and rich in nutrients, which makes for excellent insect life. Such a favorable climate creates extraordinary growing conditions for trout. For instance, a 7-inch Bighorn River rainbow trout can grow to 14 inches in a year, about three times the normal growth rate. A fingerling brown trout can grow to 16 inches in three years. Only the Beaverhead can match the Bighorn for productivity.

The Bighorn's reputation rests on its abundance of trout and their exceptional size. The record Bighorn trout is a 29-inch, 16-pound rainbow. Although few trout exceed 21 inches, the average trout is slightly more than 14 inches. The Bighorn has almost 6,000 fish per mile and over half of these are 13 inches or more, almost twice as many as the Madison and nearly three times as many as the Beaverhead.

These Bighorn fish facts are well known to trout fishing's cognoscenti, and this river's popularity has zoomed during the last two decades. During the peak periods of July, August, and September, the popular sections of the river may see well over 100 boats a day. Fortunately, this river has good fishing almost all year, so it is possible to avoid the crowds if you are willing to brave inclement weather. A National Park Service $5-per-vehicle user fee is required for floaters between Afterbay and Bighorn. Purchase permits at Quill Gordon Fly Fishers in Fort Smith or at the National Park Service Afterbay Access. No permits are required for those boating downstream from Bighorn.

Summertime moss and algae buildups can frustrate anglers-especially those with spinning gear. But the copious amounts of river vegetation attract wildlife, and the birdlife along the Bighorn can be spectacular. Shorebirds pass through this drainage in large numbers, and the river sees heavy waterfowl use during migration. In fact, up to 20,000 mallards winter on the river, and these ducks attract raptors like bald eagles and, occasionally, peregrine falcons. Afterbay is a favorite winter and spring spot for serious bird watchers.

The upper 44 miles of the river in Montana flow through the Crow Indian Reservation. Recreational use of this portion of the Bighorn, particularly for fishing and hunting, has been a controversial topic for several decades. In 1976 the Crow Tribe declared the river off-limits to non-tribal members. This initiated a legal debate that was resolved by a 1978 Supreme Court decision that ruled the river bed belongs to the State of Montana, not the Crow Tribe.

The state reopened the section of the Bighorn which flows through the reservation to public fishing in 1981. Be aware that on the reservation, recreational use is only permissible below the high-water marks. Hunting big game is not allowed and upland bird hunting is only allowed on deeded land. Waterfowl hunting is only permitted within the high-water marks.

Access to the Bighorn is limited, but adequate. Most floating occurs immediately below the dam in the 12-mile section between Afterbay and the Bighorn access. While the trout habitat between Bighorn and Mallard's Landing isn't as good, the fishing pressure is considerably lower and the fishing is still excellent.

Below Hardin, it is a warm-water fishery with limited populations of sauger, channel catfish, burbot, and smallmouth bass. This section also has good waterfowl concentrations and receives some hunting pressure. The Crow Reservation stops at Hardin. Floating pressure below Hardin is light. Access can be difficult, however, as the river flows mostly through private land.

Floaters use all kinds of crafts on the Bighorn, including motorboats and jet boats (no motors allowed above Bighorn access). Practiced beginners can handle the Bighorn. The main channel splits occasionally, and snags in the river can cause problems for the unwary. High winds can be a problem, too. Watch for the low diversion dam on the downstream side of the old Two Leggins Bridge. Below Hardin, watch for the Victory and Manning diversion dams.

Excerpted from Paddling Montana by Hank Fisher
(Copyright 2000, Falcon Publishing, Inc.)

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