Spate · Granite · Corsica / Corse-du-Sud (Ajaccio hinterland)

Gravona

Gravona terrain map
Terrain map

Mediterranean torrent flowing from central Corsican mountains to the west coast, steep, technical river where light bounces off white rock and the air carries salt.

Poor · Brown Trout
CDC Emerger · 16-18
Poorlive now
Not the day for it
River temperature is the limiting factor today, not the flow. This is not the day to push it. Check the thermal advice above before you head out.
90% confidence
What moved it
  • LevelDry recentlyNo gauge reading
  • Water temp22.0°C
  • ClarityClear
Today’s fly
CDC Emerger
CDC Emerger16-18
Dead-drift
Conditions on the water
Estimate
Level
Dry recently
No gauge reading
Water temp22.0°C
ClarityClear
Weather24°C
WindNE 3 km/h
Pressure1017 hPa
Rain · recent0.0 mm
Rain · ahead0.0 mm

No gauge on this water — readings are regional estimates from weather, not a live gauge.

Water temperature for brown trout
Warm — slow
22°C est.ideal 10–16°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 22°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
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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Evidence
Survey-backed · regionalModerate confidence

Backed by regional invertebrate surveys; no sampling on this exact reach yet.

Through the year
0–3 scale · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
March BrownHatch
2
3
2
GrannomHatch
2
2
Large StoneflyHatch
2
3
2
Yellow SallyHatch
2
3
2

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.
  • Réglementation de Corse-du-Sud
  • Carte de pêche obligatoire
  • Développement actif du no-kill.
What's coming
Plan ahead
5-day outlook
Water here around 22°C. Nothing cooler within range — carry a thermometer.
About this water

Mediterranean torrent flowing from central Corsican mountains to the west coast, steep, technical river where light bounces off white rock and the air carries salt. Tight, cascading pocket water requiring short-line nymphing and small dry flies. Endemic Corsican trout (macrostigma lineage) in cold, oxygenated flows. Clear water, conservative fish, ethics-heavy approach. No-kill conservation developing. Check Corse-du-Sud regulations.

  • Granite
Water quality (WFD)
  • Ecology: Good
  • Chemical: Unknown

WFD classification · FRER39

The full read · show the working · for brown trout · confidence 90%
How the 12 is built — score × weight = contribution
Temperature6 × 28%1.7
Flow60 × 22%13.2
Clarity95 × 18%17.1
Feeding Time40 × 13%5.2
Pressure80 × 7%5.6
Insect activity38 × 12%4.6
Limiting factor: Water temperature (22°C) is outside Brown Trout's preferred range (10–16°C)= 47
Can you trust it?
Water temperatureair-to-water estimateestimated
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.
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout2nd Saturday of March → 3rd Sunday of September
Related guides
Pyrenees PlaybookFrench riversEuro Nymphingsubsurface methods
Booking & contacts