Freestone · Mixed · Montana, US

Bitterroot River

Calm stretch of the Bitterroot River with a gravel bar in the foreground and cottonwood trees along the far bank, near Victor, Montana.

The Bitterroot is the river that ends the long Montana winter.

Tomorrow · A proper day on the water
Pheasant Tail
Forecast · Tomorrow
A proper day on the water
A proper day for it. Work the seams with an upstream nymph, switch to the dry when they show.
65% projected
Today's fly
Pheasant Tail
Pheasant Tail
Conditions on the water · Tomorrow
Live gauge
Level
Rising
1.27 m
Lifting fast
Water temp12.0°C
ClarityVery coloured
Weather14°C
WindN 12 km/h
Pressure1009 hPa
Rain · recent0.0 mm
Rain · ahead6.2 mm

The nearest gauge doesn't record temperatures, so we've estimated it — defer to the river keeper's advice.

Water temperature for Rainbow Trout
Ideal
12°C est.ideal 10–18°C
0°14°28°
How to fish it · for Rainbow Trout
When
Nymphing can work through most of the day.
Where
Cover mixed depths.
Method
Start with tight-line nymphs and adjust if fish rise or drift higher.
Kit
9 ft #4 rod, floating line, 12 ft tapered leader to 4–5 lb fluoro tippet.
Why this works
Excellent — water temperature is right today, though insect activity could be better.
Likely species
Mayflies
Caddisflies
terrestrials
Hatch timeline · tomorrowPeak at 12pm

12pm(now) — Mahogany Dun

Stage: On emergersApproach: Emerger or dryActivity: 77%
Also:Reed Smut29%
Peak emergence windowWeather boostDegree-days at peak5 food groups active

Peak activity at 12pm — Mahogany Dun (Mahogany Dun, Peak emergence window)

Sub-surface · on the nymphunder the surface

Hatch predictions

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Beyond the hatch · worth watchingambient prey(1)

Hatch predictions

Top prey shown — see all 3 with Pro.

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Evidence
Records-basedModerate confidence

Based on species-occurrence records, not local invertebrate surveys.

Through the year
0–3 scale · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
2
1
1
2
2
2
2
2
2
2
Brown DunHatch
2
3
3
3
3
3
3
2
Western Green DrakeHatch
2
2
Flav (Small Western Green Drake)Hatch
2
3
2
Mahogany DunHatch
2
2

Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.

Ranked for today
Rainbow Trout fly box
SD
Sex Dungeon
2-6 · Pattern
Proven pattern for this period
Permits & access
Permit required — see local rules.
  • Montana licence
  • Spring catch-and-release and side-channel closures protect spawning — check FWP before the March skwala session.
What's coming
Plan ahead
5-day outlook
Other water nearby · 1
Rock Creek
56 km
Rainbow trout · Brown trout · Cutthroat trout
Gallery · 2
  1. Calm stretch of the Bitterroot River with a gravel bar in the foreground and cottonwood trees along the far bank, near Victor, Montana.
    bitterroot-river-near-victor-montana
  2. Terrain map of the venue
    Terrain map
About this water

The Bitterroot is the river that ends the long Montana winter. While everywhere else is still frozen shut, the skwalas start crawling and the trout start looking up, and grown men drive a long way to throw a dry fly in March. It's an easygoing valley freestone — browns, rainbows, and westslope cutthroat in long riffles and braided side channels you can wade most of. Come the June runoff it blows out brown and high, and you wait. But that early skwala window is worth the cold fingers.

  • Mixed
Water quality · US Clean Water Act
  • Aquatic life: Impaired
What this classification means

EPA ATTAINS assessment unit 'Bitterroot River' (MT76H001_020), 2021 Integrated Report. Aquatic Life use: Not Supporting. Listed impairment causes: Temperature, Hydrologic Alteration. This is a Clean Water Act assessment-unit classification (the US analogue of WFD), not a live reading.

Status is for the Clean Water Act assessment unit covering this reach.

EPA ATTAINS (Clean Water Act) · MT76H001_020

The full read · show the working · for Rainbow Trout · confidence 90%
How the 85 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity85 × 18%15.3
Feeding Time85 × 13%11.1
Pressure75 × 7%5.3
Insect activity62 × 12%7.4
Conditions total= 85
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout Third Saturday of May → Last day of February
Related guides
Euro Nymphingsubsurface methods
Booking & contacts