Freestone · Limestone · Friuli Venezia Giulia / Carnia-Alto Friuli

Tagliamento

Tagliamento terrain map

Friuli's great braided river and, by wide agreement, the last one in the Alps that still behaves like a gravel-bed river should — spreading, splitting, and cutting new channels after every flood rather than being confined behind embankments.

Poor · Marble Trout
Blue-Winged Olive · 18-20
Poorlive now
Not the day for it
Low and clear — careful approach country. A morning for the obvious fish only.
90% confidence
What moved it
  • Flow93.8 m³/sLast reading 8h ago
  • Water temp22.6°C
  • ClarityClear
Today's fly
Blue-Winged Olive
Blue-Winged Olive18-20
Upstream dry, on top
Conditions on the water
Live gauge
Flow
Steady
93.8 m³/s
Last reading 8h ago
Water temp22.6°C
ClarityClear
Weather30°C
WindS 9 km/h
Pressure1022 hPa
Rain · recent2.7 mm
Rain · ahead0.0 mm

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

Water temperature for Marble Trout
Warm — slow
23°C est.ideal 8–13°C
0°14°28°
How to fish it · for Marble Trout
When
Low light — the first and last hour of the day — brings marbles onto the shelves. Season runs 29 March to 27 September; single barbless hook, one fish a day, minimum 35cm on this stretch.
Where
Deep glides against the outer banks and the heads of the larger, more stable pools — the parts of the braid that don't move every flood.
Method
Streamer on intermediate or sink-tip through the deep water — methodical, unhurried coverage rather than blind casting across the whole braid.
Kit
9 to 10 ft #6/7, intermediate line, 8 to 10 lb fluoro, baitfish streamers. Wet net, handle in the water.
Why this works
Water at 22.6°C. This is the line where catch-and-release kills marble trout. Do not fish for them today.
Likely species
Mayflies
  • Iron BlueMost likely
    #16–18 · Dun
    Cold, grey day — the dun sits long. Good dry-fly water.
  • Large dark oliveAlso possible
    #14–16 · Emerger
    Dead-drift the emerger — it's sitting in the film.
  • Blue-winged oliveAlso possible
    #16–18 · Dun
    Duns are up; a sherry spinner fall may follow.
  • Anglers curse mayfliesAlso possibleLower confidence
    #20–22 · Spinner
    Go tiny: 20-22 spent spinner, single fly, long tippet.
Caddisflies
  • Net-spinning caddis (S. Europe)Most likelyLower confidence
    #12–14–16 · Pupa
    Widespread riffle net-spinner; evening emergence.
  • GrannomAlso possible
    #14–16 · Pupa
    Pupa first, then dries as the adults come off.
  • Satin sedgeAlso possibleLower confidence
    #12–14 · Egg-laying
    Skitter it at dusk — this one's fished, not dead-drifted.
Hatch timeline · todayPeak at 6pm

Hatch predictions

Today's headline hatch shown — see all 6 active hatches hour by hour with Pro.

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Sub-surface · on the nymphunder the surface

Hatch predictions

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 2 with Pro.

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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
Marble 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.

Permits & access
Permit required — see local rules.
  • ETPI (Ente Tutela Patrimonio Ittico) regional licence required — course-based, roughly €46 for residents
  • FVG Zone B season (2026 Calendario Pesca Sportiva): trout open 07:00 on 29 March to 27 September, with a catch-and-release-only extension to 31 October
  • Marble trout minimum size 35cm on this reach (Collegi 9/10), one fish a day
  • Grayling minimum size 60cm, and FVG limits every angler to ONE retained grayling per calendar year across the whole region
  • Single barbless hook mandatory on No-Kill and RPS water.
What's coming
Plan ahead
5-day outlook
Water here around 23°C. Nothing cooler within range — carry a thermometer.
About this water

Friuli's great braided river and, by wide agreement, the last one in the Alps that still behaves like a gravel-bed river should — spreading, splitting, and cutting new channels after every flood rather than being confined behind embankments. The middle reaches through Carnia and past Venzone hold marble trout and grayling in clear, cold water over pale limestone gravel. Read the braid rather than a single channel; a good lie this season may be a dry bar the next.

  • Limestone
The full read · show the working · for Marble Trout · confidence 90%
How the 10 is built — score × weight = contribution
Temperature7 × 28%2.0
Flow60 × 22%13.2
Clarity95 × 18%17.1
Feeding Time55 × 13%7.2
Pressure80 × 7%5.6
Insect activity60 × 12%7.2
Limiting factor: Water temperature (22.6°C) is outside Marble Trout's preferred range (8–13°C)= 52
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
What would change the calculation
Cooler water — back toward the 8–13 °C ideal band — would lift the score and ease welfare.
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout 2026-03-29 → 2026-09-27
  • Grayling 2026-06-01 → 2026-09-27

    Rules are set at province or association level — check locally.

  • Marble trout 2026-03-29 → 2026-09-27
Related guides
Grayling Playbookgrayling tacticsEuro Nymphingsubsurface methods
Booking & contacts