Montana’s Big Hole River is legendary. It is considered the quintessential Blue Ribbon trout stream in the state. This river offers 153 miles of undammed, pristine water in southwestern Montana. The river remains one of the last free-flowing rivers in the region. It flows through stunning high-elevation meadows, canyons, and vast valleys.
This guide will walk you through the fishing seasons, distinct river sections, and vital conservation rules for the Big Hole River Montana.
The Exceptional Fishery of the Big Hole River Montana
The Big Hole River is renowned for its diverse trout populations. It is home to five species of game fish. Most anglers visit for the plentiful population of large, wild Brown and Rainbow Trout.
The quality of fishing is excellent throughout the system. Trout concentrations are incredibly high in some areas. For example, the Middle Canyon section holds up to 3,000 fish per mile. Historically, the river was noted as a national destination fishery for grayling and trout as early as the late 1880s.
Big Hole River Fish Species
Five primary game species inhabit the Big Hole River. This mix includes both native and introduced populations. The river’s status as a Blue Ribbon fishery is well-deserved.
| Species | Status & Key Location | Key Characteristics |
|---|---|---|
| Brown Trout (Salmo trutta) | Most common species; dominates the lower stretches (Melrose to Twin Bridges). | Introduced in 1889. They are predaceous and often feed at night. Known for growing to large, sometimes “monster,” sizes. |
| Rainbow Trout (Oncorhynchus mykiss) | Plentiful wild populations found throughout the river system. | Introduced in 1889. Dominate Brown Trout in the Fish Trap to Melrose section (2:1 ratio). |
| Fluvial Arctic Grayling (Thymallis arcticus) | Critically important native species. This is the last stream-dwelling population in the contiguous United States. | Identified as a Fish of Special Concern. Catch-and-release is mandated for this species across the entire river. |
| Brook Trout (Salvelinus fontinalis) | Common in the headwaters and tributaries. | Introduced to Montana in 1889. They are aggressive feeders and can grow quite large in the upper sections. |
| Mountain Whitefish (Prosopium williamsoni) | Abundant native fish found throughout the Big Hole River. | Often caught by trout anglers. They are an underrated sport fish, especially during shoulder seasons. |
The Big Hole River flows for approximately 153 miles. Its varied course is often divided into four distinct sections for anglers. This journey provides many different types of water and scenery.
Headwaters (Skinner Lake to North Fork/Wisdom)
This river section begins at Skinner Lake in the Beaverhead Mountains. It is characterized as a slow-moving, high-meadow stream. The water lazily winds through agricultural land and willow-lined bottoms.
This area is the last stronghold for the native fluvial Arctic Grayling. Anglers targeting the Grayling must release them immediately. Wade fishing here is excellent for smaller fish, typically 10 to 14 inches.
Upper Big Hole (North Fork to Dewey/Wise River)
The North Fork joins the main river near Wisdom, which significantly increases the water volume. This stretch becomes floatable and presents the chance for larger fish, including Brown Trout.
The Wise River confluence provides a “breath of cold clear water” in the summer months. This cold input helps rejuvenate this stretch during high temperatures.
Middle Canyon (Dewey to Salmon Fly FAS/Melrose)
This stretch is considered the prime fishing area on the Big Hole River. It showcases a steeper gradient with swift pocket water and deep pools. Rainbow Trout outnumber Brown Trout by about two to one here.
The Middle Canyon has the highest concentration of trout, with up to 3,000 fish per mile. This section is also famous for hosting some of the heaviest insect hatches.
Lower Big Hole (Melrose to Twin Bridges/Jefferson River Confluence)
Below Melrose, the river transitions toward arid plains and large cottonwood bottoms. The water pace slows down, creating classic riffles and long, slow pools.
In this lower stretch, Brown Trout dominate Rainbow Trout by a 2:1 ratio. This area is locally considered the best spot to hook a Brown Trout over five pounds, often called a “monster”. This section generally experiences lower angling pressure, which can provide more solitude.
Seasonal Fly Fishing on the Big Hole River Montana
Timing your trip to the Big Hole River Montana is crucial due to the distinct seasonal flow and hatch cycles. Recreational use on the river, combining both angling and non-angling activities, is highest in July.
Spring Fishing and Runoff (April to June)
The season kicks off with the pre-runoff period, from mid-April through May. Anglers eagerly anticipate heavy hatches like Skwala stoneflies, Baetis mayflies, and the Mother’s Day caddis. Many local anglers consider this period the best time to target the river’s largest fish using big streamers. This period sees low pressure from the public.
The famed Salmon Fly hatch typically runs for a three-week window in June. These bugs are as large as a finger and draw actively feeding fish to the surface. Smaller Golden Stonefly hatches keep the action high after the Salmonflies subside.
Summer Challenges (July to September)
Summer fishing runs from July through September. Hatches include Pale Morning Duns (PMDs) and Yellow Sally Stoneflies. Terrestrials like grasshoppers, ants, and spruce moths also offer great dry-fly action. Trout show no hesitation when eating a well-presented spruce moth imitation.
However, the Big Hole River can experience warm water temperatures. Water above 70°F is stressful and potentially fatal to trout. This is why summer fishing may be subject to severe restrictions.
Fall Fishing (September to November)
Fall is a favorite time for many Big Hole anglers. The water temperatures are cooler, and river congestion is low. Brown Trout become aggressive as they prepare for their fall spawning season. Using streamers is highly effective when targeting these aggressive brown trout.
The river is generally not suitable for winter fishing, as much of the course freezes completely over.
Conservation and Access for Anglers on the Big Hole River Montana
The Big Hole River faces threats from drought, declining fish populations, and habitat degradation. Its continued health depends on cooperation between local groups and anglers.
Regulations and Special Gear for the Big Hole River
All anglers must have a valid Montana Fishing License, a Conservation License, and an Aquatic Invasive Species (AIS) Prevention Pass.
To address declining trout populations, strict rules have been implemented.
- Catch-and-Release: The entire river mandates catch-and-release for the native Arctic grayling.
- Restricted Section: The section from Dickie Bridge to the mouth is entirely Catch-and-Release only for trout from April 1 through September 30.
- Terminal Tackle: In the Dickie Bridge to the mouth section, only artificial lures and single-pointed hooks are allowed. Anglers must replace any treble or double hooks with a single hook. Artificial lures mean no live or dead bait.
Anglers are strongly encouraged to use artificial lures over bait to reduce deep hooking mortality. Other best practices include using barbless hooks, rubber nets, and heavier gear to land fish quickly.
Managing Drought and Closures (Hoot-Owl Restrictions)
The Big Hole Watershed Committee (BHWC), formed in 1995, manages the Drought Management Plan (DMP). The DMP aims to mitigate the effects of low flows and high temperatures.
- Hoot-Owl Closures: During hot, dry summers, emergency restrictions, known as “Hoot-Owl” closures, may be posted. Hoot-Owl restrictions suspend fishing from 2:00 p.m. until midnight.
- Triggers: Closures are triggered when water temperature exceeds 70°F, a level considered stressful for trout (salmonids), or when stream flows drop too low.
- Flow Monitoring: Flow levels are measured in cubic feet per second (cfs) at USGS stations. For instance, Section V (Tony Schoonen FAS to the Jefferson River) closes if flow drops to 100 cfs.
- Lifting Closures: Temperature-based restrictions are automatically lifted on September 15th.
Anglers are urged to voluntarily stop fishing when water temperatures rise above 67°F.
Public Access Points on the Big Hole River Montana
Access along the Big Hole River is considered excellent for much of its length. Public access is provided through numerous designated Montana Fish, Wildlife & Parks (FWP) Fishing Access Sites (FAS). Many FAS locations offer convenient amenities like designated parking and restrooms.
Some popular Fishing Access Sites include:
- Maidenrock FAS: A large site covering nearly 200 acres.
- Salmon Fly FAS: Located near Melrose.
- Glen FAS and Tony Schoonen FAS: Located further downstream toward the confluence.
The river is classified as a Class I water from the Fishtrap FAS downstream to the Jefferson River confluence, which confirms the level of public access for recreational purposes.
Preserve the Legacy of the Big Hole River Montana
The Big Hole River Montana is a rare gem, celebrated for its spectacular scenery, diverse wild trout, and its status as the last refuge for native fluvial Arctic grayling in the lower 48 states. The valley offers open vistas and mountains.
The longevity of this blue-ribbon fishery depends on human stewardship. Cooperation between ranchers, anglers, and conservation groups has been instrumental in keeping the river healthy. By following the strict regulations, respecting access guidelines, and adhering to drought-related restrictions, we can ensure the sustainability of this essential Montana treasure.
Frequently Asked Questions (FAQ) about Big Hole River Montana
What makes the Big Hole River unique among Montana rivers?
The Big Hole River is one of the last free-flowing, undammed rivers in the region. It is the sole remaining habitat in the contiguous United States for the native stream-dwelling Fluvial Arctic Grayling.
Are there special fishing restrictions on the Big Hole River?
Yes, mandatory regulations protect the fishery. Catch-and-release is required for all Arctic grayling. Furthermore, the section from Dickie Bridge to the river’s mouth is catch-and-release only for trout and requires the use of artificial lures and single-pointed hooks.
What is a “Hoot-Owl” restriction?
A Hoot-Owl restriction is an emergency closure mandated by Montana FWP during hot, dry periods. This restriction prohibits fishing during the warmest part of the day, typically from 2:00 p.m. to midnight, to protect trout from stress caused by high water temperatures (above 70°F).
What are the best times to fish the Big Hole River?
Fishing is generally strong from April (pre-runoff hatches) through June (Salmon Fly hatch) and again in the Fall (September to November). Fall is often preferred due to cooler water temperatures and reduced crowds.
Where does the Big Hole River get its name?
The river is named after the vast, high-elevation valley it flows through in southwestern Montana. Early trappers referred to this large, open basin as a “big hole”.
The health of the Big Hole River is a shared responsibility. Ready to explore this world-class fishery or concerned about its future? Support the organizations dedicated to protecting its delicate ecosystem, especially the native Arctic grayling.
Support the Big Hole Watershed Committee’s Conservation Efforts Today
