Freestone · Granite · Hautes-Pyrénées / Cauterets, FR

Gave du Marcadau

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

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

Poor · Grayling
Pink Grayling Bug · Hook 16
Closed season
Out of season. Try elsewhere.
Closed — confidence not applicable today.
What moved it
  • LevelModerate rain recentlyNo gauge reading
  • Water temp5.7°C
  • ClarityClearing
Today's fly
Pink Grayling Bug
Pink Grayling BugHook 16
in season · all-rounder
Conditions on the water
Estimate
Level
Moderate rain recently
No gauge reading
Water temp5.7°C
ClarityClearing
Weather4°C
WindS 10 km/h
Pressure1013 hPa
Rain · recent21.9 mm
Rain · ahead12.5 mm

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

Water temperature for Grayling
Ideal
6°C est.ideal 4–14°C
0°14°28°
How to fish it · for Grayling
When
Autumn — September through October prime in this high-altitude tributary. Grayling are present but sparse.
Where
Slower glides in the lower Marcadau where the gradient eases. Above the steeper sections is brown-trout-only pocket water.
Method
Euro-nymphing through the slower pockets; dries on autumn afternoons when the air warms.
Kit
10 ft #3 nymphing rod for the deep pockets; 9 ft #4 for dries. 4 to 5 lb fluoro tippet, 12 ft leader.
Likely species
Stoneflies
Hatch timeline · todayQuiet day

Hatch predictions

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Sub-surface · on the nymphunder the surface

Hatch predictions

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Evidence
Survey-backed · regionalHigh confidence

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

Through the year
0–3 scale · November 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
Grayling fly box

French nymph-first water. Fast current, technical presentation, weighted nymphs and emergers, with dry flies when fish rise.

Small Perdigón
Small Perdigón
Hook 14–18 · Fly
in season
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
Gave d'Estaubé
21 km
0
Brown trout · Grayling
Lac des Especières
17 km
Brown trout
La Truite des Pyrénées
19 km
Rainbow trout · Brown trout
Ara
28 km
Brown trout
Río Gállego
28 km
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

~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.

Hatches & food

In the Pyrenean gaves and headwater torrents, resident brown trout move from early-season olives and March browns into strong spring and early-summer stonefly activity, then a long spell of evening caddis and small buzzers, with terrestrials most relevant on wooded lower gaves and much less important high above the tree line.

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

WFD classification · FRFRR245_3

The full read · show the working · for Grayling · confidence 50%
How the 0 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow95 × 22%20.9
Clarity85 × 18%15.3
Feeding Time15 × 13%2.0
Pressure80 × 7%5.6
Insect activity11 × 12%1.3
Conditions total= 73
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
  • Trout 2nd Saturday of March → 3rd Sunday of September
  • Grayling 3rd 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
At a glance

Gave du Marcadau is a freestone river in Hautes-Pyrénées / Cauterets, France. Its recorded elevation is about 1,621 m above sea level and the catchment geology is granite. The river is described as roughly 15 km long. Our data lists brown trout and grayling here. The trout season is recorded as running from 2nd Saturday of March to 3rd Sunday of September. The grayling season is recorded as running from 3rd Saturday of May to 3rd Sunday of September. Best window recorded for anglers: March–September. Core methods listed: Euro nymphing; dry fly; small Spey casting. Its recorded parent river is the Gave De Pau. Its Water Framework Directive ecological status is recorded as good. Access is recorded as day tickets through the local AAPPMA (angling association). Nearby waters in our listings include Lac des Especières at 17 km, La Truite des Pyrénées at 19 km and Gave d'Estaubé at 21 km.