Freestone · Granite · Hautes-Pyrénées / Cauterets

Gave du Marcadau

A rocky mountain stream, the Gave du Marcadau, running through a green valley with Pyrenean peaks in the background near Cauterets.
Contributor photo

Cauterets, vallee du Marcadau

LaurPhil - CC BY 2.0

Tributary of the Gave de Pau at Cauterets, flowing through a granite valley where the light seems to sharpen the mountains.

Good · Brown Trout
Small Perdigón · 16-20
Goodlive now
A proper day on the water
Low and clear — careful approach country. Stay small, stay accurate.
75% confidence
What moved it
  • LevelDry recentlyNo gauge reading
  • Water temp14.6°C
  • ClarityClear
Today’s fly
Small Perdigón
Small Perdigón16-20
Euro-nymph
Conditions on the water
Estimate
Level
Dry recently
No gauge reading
Water temp14.6°C
ClarityClear
Weather13°C
WindS 6 km/h
Pressure1019 hPa
Rain · recent0.0 mm
Rain · ahead3.0 mm

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

Water temperature for brown trout
Ideal
15°C est.ideal 10–16°C
0°14°28°
How to fish it · for brown trout
When
Late spring through early autumn — high alpine tributary, fishes only when snow has cleared. June through September realistically.
Where
Pocket water through the Cauterets valley. High Pyrenean character — clear cold water, intimate scale.
Method
Short upstream dry-dropper to wild fish in pocket water. The Marcadau is small mountain water — short casts, quiet wading.
Kit
8 ft #3 — small alpine stream. Floating line, 9 to 12 ft leader to 4 lb fluoro. Studded boots.
Why this works
Good — water temperature is working for you, but time of day is the limiting factor today.
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 · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
Grayling seasonSeason
1
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 permits
  • Fly-only sections common in Pyrenees.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Lac des Especières
28 km
Brown trout
Cinca
41 km
34
Brown trout
Ara
43 km
Brown trout
Gave d'Estaubé
47 km
76
Brown trout · Grayling
Gave d'Ossau
48 km
31
Brown trout
Gallery · 2
  1. A rocky mountain stream, the Gave du Marcadau, running through a green valley with Pyrenean peaks in the background near Cauterets.
    Cauterets, vallee du Marcadau
  2. Terrain map of the venue
    Terrain map
About this water

Tributary of the Gave de Pau at Cauterets, flowing through a granite valley where the light seems to sharpen the mountains. ~1300 m designated no-kill fly-only (barbless hooks required). Wild brown trout in pristine conditions. High altitude, short season, responsive to snowmelt. Best from June when water clears.

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

WFD classification · FRFRR245_3

The full read · show the working · for brown trout · confidence 75%
How the 74 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow60 × 22%13.2
Clarity95 × 18%17.1
Feeding Time40 × 13%5.2
Pressure80 × 7%5.6
Insect activity42 × 12%5.0
Conditions total= 74
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
Apple MapsGoogle Maps
Seasons & zones
  • Trout2nd Saturday of March → 3rd Sunday of September
  • Grayling3rd Saturday of May → 3rd Sunday of September

    France national rule: grayling opens 3rd Saturday of May in all waters. In 1st category (salmonid) rivers, grayling closes with the trout season on the 3rd Sunday of September. Departmental regulations may impose additional restrictions. Always check the relevant département's 2026 arrêté préfectoral.

Related guides
Grayling Playbookgrayling tacticsPyrenees PlaybookFrench riversEuro Nymphingsubsurface methods
Booking & contacts