Big Hole River Fishing Forecast
Famous for salmonfly hatch and native Arctic Grayling - last fluvial grayling population in lower 48 states
Opens 3rd Sat in May
Western District general season. Some sections have extended or special regs
Today's Fishing Conditions
Fair
Updated 1:44 AM
45°F
605 CFS
3 AM - 5 AM
WD-40
7-Day Forecast
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Quick Facts
Brown Trout, Rainbow Trout, Brook Trout, and Arctic Grayling
freestone
36°F - 45°F
March Fishing Tactics
Primary Targets
Recommended Tactics
Early hatches begin. Look for BWOs.
March Hatches
BWO
Mayfly
Best on overcast days. RS2, Parachute Adams. Spring and fall.
Midge
Midge
Winter staple. Zebra midges, WD-40.
Year-Round Fishing Guide
| Month | Water Temp | Tactics |
|---|---|---|
| January | 32-38°F | Deep nymphing, Midges, Streamers |
| February | 33-40°F | Midges, Small nymphs, Deep pools |
| March(Now) | 36-45°F | BWO dries, Streamers, Early stonefly nymphs |
| April | 40-50°F | Skwala dries, BWO patterns, Streamers |
| May | 45-55°F | Mother's Day Caddis, Nymphing, Streamers |
| June | 50-60°F | Salmonfly dries, Golden Stones, PMDs |
| July | 55-68°F | PMDs, Hoppers, Caddis, Attractor dries |
| August | 55-70°F | Hoppers, Tricos, PMDs, Terrestrials |
| September | 48-58°F | BWOs, Streamers, Hoppers |
| October | 40-50°F | Streamers, BWOs, Egg patterns |
| November | 35-42°F | Streamers, Deep nymphs, Egg patterns |
| December | 32-38°F | Deep nymphs, Midges, Slow presentations |
Spawning Seasons
Please respect spawning fish and their redds. Avoid fishing over actively spawning trout.
Brown Trout
Spawn months: October, November
Night spawning common. Males become very dark with pronounced kype during spawn.
Rainbow Trout
Spawn months: March, April
Resident rainbow trout spawn in smaller tributaries and tend to build smaller redds than steelhead.
Brook Trout
Spawn months: September, October
Males develop vibrant red bellies and white-edged fins during spawning. Early fall spawners.
Access Points & Parking for Big Hole River
Wisdom
Upper river access in the Big Hole Valley.
Divide
Mid-river access.
Melrose
Lower river access with services.
Glen
Lower canyon access.
How to Fish Big Hole River: Tips & Tactics
The Big Hole River is Montana's last stronghold of fluvial Arctic grayling, alongside excellent populations of brown and rainbow trout. This is classic Montana ranching country.
Best Times of Day
The salmonfly hatch in late June is legendary. Summer offers excellent dry fly fishing. Fall brings aggressive brown trout feeding.
Recommended Techniques
Float fishing covers the most water. Match the prolific hatches - salmonflies, caddis, and mayflies. Target Arctic grayling in the upper river.
Water Conditions
The Big Hole can experience low summer flows. Hoot-owl restrictions may apply. The valley is stunning ranching country.
Fly Selection
Salmonfly and golden stonefly patterns for early summer. Caddis and mayflies throughout. Hoppers in late summer.
Local Knowledge
Hoot-owl restrictions close fishing during hot afternoons in summer. Arctic grayling are special - handle carefully. The upper river is the grayling stronghold.
Local Tips
The Big Hole Valley is authentic Montana ranching country. Arctic grayling are a special treat. Watch for hoot-owl restrictions in summer.
When is the Best Time to Fish Big Hole River?
Spring
Skwala and March browns begin the season.
Summer
Salmonfly hatch in late June. Watch for hoot-owl closures.
Fall
Brown trout become aggressive. Excellent conditions.
Winter
Limited but fishable on mild days.
Recommended Equipment for Big Hole River
Rod
9-foot, 5 or 6-weight for most fishing.
Line
Floating line for dries and nymphing.
Leader & Tippet
9-foot tapered leader, 4X-5X tippet.
Waders
Breathable waders. The Big Hole is wadeable in many sections.
Essential Flies
Big Hole River Fishing Regulations
Season
Open year-round.
Limits
Arctic grayling must be released. Trout limits vary.
Special Regulations
Hoot-owl restrictions may apply. Check FWP.
Bait Restrictions
Artificial flies and lures only.
Notes
Protecting Arctic grayling is critical.
Always verify current regulations with Montana fish and wildlife agency before fishing. Regulations can change annually.
Fly Shops & Guides Near Big Hole River
Local Fly Shops
- Frontier Anglers - Dillon
- Big Hole Lodge
- Complete Fly Fisher
Guide Services
- Frontier Anglers
- Big Hole Guides
- Complete Fly Fisher Guides
Optimal Fishing Conditions
Optimal Flow
500 - 1500 CFS
Best fishing conditions
Optimal Water Temperature
50° - 65°F
Ideal for active trout
Other Montana Trout Rivers
Bitterroot
Blackfoot
Yellowstone (inside YNP)
Madison
Missouri (below Holter)
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