Rules at a glance
- Free fishing
- Fly only
Water temperature for Brown Trout
Warm — slow22.1°Cideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
The season opens mid-February and there's usually something hatching by March if the weather cooperates, which in the Alps is never guaranteed. Fishing settles into the classic pattern after that — spring mornings, summer dawn-and-dusk once the meltwater gets moving, a solid autumn window once the glaciers stop contributing.
Where
The upper valley above Moso/Moos is faster, tighter water — pocket water and short riffles. Down towards Merano the gradient eases and the pools lengthen, the same stretch where marble trout start showing up.
Method
Upstream nymph through the broken upper water; switch to dry-dropper as the valley opens out. Barbless single hook — much of this river runs under one form of no-kill or another, so check the specific stretch before you start.
Kit
9 to 10 ft #4 for a medium Alpine freestone river. Floating line, 12 ft leader to 4-5 lb fluoro. Studded boots for the cobble.
Why this works
Water at 22.1°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Likely species
Caddisflies
Caddisflies- Net-spinning caddis (S. Europe)Most likelyLower confidence#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- GrannomAlso possible#14–16 · PupaPupa first, then dries as the adults come off.
Hatch timeline · todayPeak at 6pm
Hatch predictions
See the full hour-by-hour hatch timeline with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 2 with Pro.
Start free trial14-day free trial. Cancel anytime.
Evidence
Survey-backed · regionalModerate confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Brown Trout fly box
12-16 · Pattern
Upstream dry, on top
12-16 · Gammarus Scud
Dead-drift, sub-surface
Permits & access
Permit required — see local rules.
- Marble trout carry a year-round no-take rule (reservoirs excepted); brown trout have a 25cm minimum size and a 1 Dec-second Saturday of Feb closed season; grayling a 33cm minimum and a 1 Jan-31 May closed season
- Individual concession-holders can extend or tighten these rules for their own stretch.
What's coming
Plan ahead
5-day outlook
Water here at 22.1°C. Nothing cooler within range.
The full read · show the working · for Brown Trout · confidence 90%
How the 12 is built — score × weight = contribution
Temperature6 × 28%1.7
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity62 × 12%7.4
Limiting factor: Water temperature (22.1°C) is outside Brown Trout's preferred range (10–16°C)= 59
Can you trust it?
Water temperaturelive gauge readinggauge
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
Directions
Seasons & zones
- Trout 2026-02-15 → 2026-11-30
- Grayling 2026-06-01 → 2026-11-30
Rules are set at province or association level — check locally.
- Marble trout 2026-02-15 → 2026-11-30
Related guides
Booking & contacts
Passirio
Water temperature for Brown Trout
Warm — slow22.1°Cideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
The season opens mid-February and there's usually something hatching by March if the weather cooperates, which in the Alps is never guaranteed. Fishing settles into the classic pattern after that — spring mornings, summer dawn-and-dusk once the meltwater gets moving, a solid autumn window once the glaciers stop contributing.
Where
The upper valley above Moso/Moos is faster, tighter water — pocket water and short riffles. Down towards Merano the gradient eases and the pools lengthen, the same stretch where marble trout start showing up.
Method
Upstream nymph through the broken upper water; switch to dry-dropper as the valley opens out. Barbless single hook — much of this river runs under one form of no-kill or another, so check the specific stretch before you start.
Kit
9 to 10 ft #4 for a medium Alpine freestone river. Floating line, 12 ft leader to 4-5 lb fluoro. Studded boots for the cobble.
Why this works
Water at 22.1°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Likely species
Caddisflies
- Net-spinning caddis (S. Europe)Most likelyLower confidence#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- GrannomAlso possible#14–16 · PupaPupa first, then dries as the adults come off.
Hatch timeline · todayPeak at 6pm
Hatch predictions
See the full hour-by-hour hatch timeline with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 2 with Pro.
Start free trial14-day free trial. Cancel anytime.
Evidence
Survey-backed · regionalModerate confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Brown Trout fly box
12-16 · Pattern
Upstream dry, on top
12-16 · Gammarus Scud
Dead-drift, sub-surface
Permits & access
Permit required — see local rules.
- Marble trout carry a year-round no-take rule (reservoirs excepted); brown trout have a 25cm minimum size and a 1 Dec-second Saturday of Feb closed season; grayling a 33cm minimum and a 1 Jan-31 May closed season
- Individual concession-holders can extend or tighten these rules for their own stretch.
What's coming
Plan ahead
5-day outlook
Water here at 22.1°C. Nothing cooler within range.
The full read · show the working · for Brown Trout · confidence 90%
How the 12 is built — score × weight = contribution
Temperature6 × 28%1.7
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity62 × 12%7.4
Limiting factor: Water temperature (22.1°C) is outside Brown Trout's preferred range (10–16°C)= 59
Can you trust it?
Water temperaturelive gauge readinggauge
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
Directions
Seasons & zones
- Trout 2026-02-15 → 2026-11-30
- Grayling 2026-06-01 → 2026-11-30
Rules are set at province or association level — check locally.
- Marble trout 2026-02-15 → 2026-11-30
Related guides
Booking & contacts