Mayflies
Limestone river flowing south from Trentino through the Val del Chiese with clear water that demands technical fishing. Marble trout, brown trout, and grayling present. Dam-regulated sections shape the flow pattern.
- Limestone
Rules at a glance
- Licence required
Water temperature for Brown Trout
Ideal13°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Through the Italian trout season — afternoon hatches in spring; sedges through summer evenings; small dark flies into autumn.
Where
Pool tails and the deeper edges of pockets through the upper river; the lower Chiese widens into longer glides as it crosses into Lombardy.
Method
Upstream nymph through the broken water; dry to risers in the glides. Italian No-Kill stretches mandate single barbless — comply or fish elsewhere.
Kit
9 to 10 ft #4 for medium freestone with Alpine clarity. Floating line, 12 ft leader to 4 to 5 lb fluoro. Studded boots — Alpine cobble runs slick.
Why this works
Excellent — water temperature is right today, though time of day could be better.
Likely species
Mayflies
- Blue-winged oliveMost likely#16–18 · DunDuns are up; a sherry spinner fall may follow.
- Anglers curse mayfliesAlso possibleLower confidence#20–22 · SpinnerGo tiny: 20-22 spent spinner, single fly, long tippet.
Hatch timeline · todayQuiet day
Hatch predictions
Today's headline hatch shown — see all 12 active hatches hour by hour with Pro.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 4 guilds with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 3 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
Alpine RhithrogenaHatch
2
3
3
2
Sculpin / Baitfish (Rivers)Hatch
2
3
3
3
3
3
3
3
2
March BrownHatch
2
3
2
Large StoneflyHatch
2
3
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Brown Trout fly box
A fuller Italian trout and grayling box for the southern Alps and northern limestone/alpine systems. It keeps the marble-trout streamer accent, but adds proper grayling dries and bugs, competition nymphs, caddis/olive work, terrestrials, pocket-water dries and alpine lake patterns.
12-16 · Pattern
Upstream dry, on top
Permits & access
Permit required — see local rules.
- Italian fishing license (permesso di pesca) varies by provincia (province)
- Barbless hooks often required on protected waters
- Catch limits may apply.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 1
Terrain map
About this water
Water quality (WFD)
- Ecology: Good
- Chemical: Unknown
WFD classification · IT22E200000000090TN
The full read · show the working · for Brown Trout · confidence 75%
How the 83 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time50 × 13%6.5
Pressure80 × 7%5.6
Insect activity66 × 12%7.9
Conditions total= 83
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout 2026-02-15 → 2026-10-07
- Grayling varies_by_water → varies_by_water
Italian Alpine grayling (temolo) — season varies by zona and managed by Trentino associations. Many grayling sections are no-retention or have strict seasonal restrictions. Check with local association or pescatrentino.it for specific Chiese/Val del Chiese section rules before fishing.
Rules are set at province or association level — check locally.
- Marble trout 2026-03-01 → 2026-09-30
Related guides
Booking & contacts
Chiese
Limestone river flowing south from Trentino through the Val del Chiese with clear water that demands technical fishing.
Water temperature for Brown Trout
Ideal13°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Through the Italian trout season — afternoon hatches in spring; sedges through summer evenings; small dark flies into autumn.
Where
Pool tails and the deeper edges of pockets through the upper river; the lower Chiese widens into longer glides as it crosses into Lombardy.
Method
Upstream nymph through the broken water; dry to risers in the glides. Italian No-Kill stretches mandate single barbless — comply or fish elsewhere.
Kit
9 to 10 ft #4 for medium freestone with Alpine clarity. Floating line, 12 ft leader to 4 to 5 lb fluoro. Studded boots — Alpine cobble runs slick.
Why this works
Excellent — water temperature is right today, though time of day could be better.
Likely species
Mayflies
- Blue-winged oliveMost likely#16–18 · DunDuns are up; a sherry spinner fall may follow.
- Anglers curse mayfliesAlso possibleLower confidence#20–22 · SpinnerGo tiny: 20-22 spent spinner, single fly, long tippet.
Hatch timeline · todayQuiet day
Hatch predictions
Today's headline hatch shown — see all 12 active hatches hour by hour with Pro.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 4 guilds with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 3 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
Alpine RhithrogenaHatch
2
3
3
2
Sculpin / Baitfish (Rivers)Hatch
2
3
3
3
3
3
3
3
2
March BrownHatch
2
3
2
Large StoneflyHatch
2
3
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Brown Trout fly box
A fuller Italian trout and grayling box for the southern Alps and northern limestone/alpine systems. It keeps the marble-trout streamer accent, but adds proper grayling dries and bugs, competition nymphs, caddis/olive work, terrestrials, pocket-water dries and alpine lake patterns.
12-16 · Pattern
Upstream dry, on top
Permits & access
Permit required — see local rules.
- Italian fishing license (permesso di pesca) varies by provincia (province)
- Barbless hooks often required on protected waters
- Catch limits may apply.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 1
Terrain map
About this water
Limestone river flowing south from Trentino through the Val del Chiese with clear water that demands technical fishing. Marble trout, brown trout, and grayling present. Dam-regulated sections shape the flow pattern.
- Limestone
Water quality (WFD)
- Ecology: Good
- Chemical: Unknown
WFD classification · IT22E200000000090TN
The full read · show the working · for Brown Trout · confidence 75%
How the 83 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time50 × 13%6.5
Pressure80 × 7%5.6
Insect activity66 × 12%7.9
Conditions total= 83
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout 2026-02-15 → 2026-10-07
- Grayling varies_by_water → varies_by_water
Italian Alpine grayling (temolo) — season varies by zona and managed by Trentino associations. Many grayling sections are no-retention or have strict seasonal restrictions. Check with local association or pescatrentino.it for specific Chiese/Val del Chiese section rules before fishing.
Rules are set at province or association level — check locally.
- Marble trout 2026-03-01 → 2026-09-30
Related guides
Booking & contacts