Freestone · Granite · Alpes-Maritimes / Mercantour

Vésubie

Vésubie venue image
Marginal · Brown Trout
Small Perdigón · 16-20
Marginallive now
Slow going — pick your moments
River temperature is the limiting factor today, not the flow. Fish dawn or dusk if you go at all, and handle everything with extra care.
80% confidence
What moved it
  • LevelProxyvia Arc (Bessans reach)
  • Water temp19.1°C
  • ClarityClear
Today's fly
Small Perdigón
Small Perdigón16-20
Euro-nymph
Conditions on the water
Proxy gauge
Level
Falling
Proxy
via Arc (Bessans reach)
Water temp19.1°C
ClarityClear
Weather21°C
WindNE 3 km/h
Pressure1019 hPa
Rain · recent5.5 mm
Rain · ahead5.3 mm

No gauge on this water — conditions are inferred from Arc (Bessans reach). The trend transfers, the absolute level does not.

Water temperature for Brown Trout
Warm — slow
19°C est.ideal 1016°C
0°14°28°
How to fish it · for Brown 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
Water at 19.1°C — above the brown trout caution line (18°C). Fish dawn or dusk only. Land it fast, wet hands, no air shots.
Hatch timeline · todayPeak at 6pm

Hatch predictions

Today's headline hatch shown — see all 8 active hatches hour by hour with Pro.

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Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 3 guilds with Pro.

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 2 with Pro.

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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
Trout seasonSeason
1
2
2
2
2
2
1
Alpine RhithrogenaHatch
2
3
3
2
Sculpin / Baitfish (Rivers)Hatch
2
3
3
3
3
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1

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

Ranked for today
Brown Trout fly box
Permits & access
Permit required — see local rules.
  • AAPPMA Alpes-Maritimes
  • Storm Alex reconstruction ongoing — check access and parcours availability before travelling.
What's coming
Plan ahead
5-day outlook
Water here around 19°C. Nothing cooler within range — carry a thermometer.
Gallery · 1
  1. Terrain map of the venue
    Terrain map
Water quality (WFD)
  • EcologyGood
  • ChemicalUnknown

WFD classification · FRDR80

The full read · show the working · for Brown Trout · confidence 80%
How the 33 is built — score × weight = contribution
Temperature38 × 28%10.6
Flow95 × 22%20.9
Clarity95 × 18%17.1
Feeding Time55 × 13%7.2
Pressure80 × 7%5.6
Insect activity67 × 12%8.0
Conditions total= 69
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowproxy via Arc (Bessans reach)proxy
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.
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
  • Trout 2nd Saturday of March3rd Sunday of September
Related guides
Booking & contacts