Spate · Granite · Brittany / South Finistère

Isole

Photo of Isole
Contributor photo

Isole — image via Wikipedia (Isole)

Lanzonnet <CC BY-SA 3.0>, via Wikimedia Commons

Tributary of the Ellé at Quimperlé described as a wild-trout paradise where Armorican granite creates clear, responsive water.

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.
80% confidence
What moved it
  • LevelDry recentlyNo gauge reading
  • Water temp21.7°C
  • ClarityClear
Today’s fly
CDC Emerger
CDC Emerger16-18
Dead-drift
Conditions on the water
Estimate
Level
Dry recently
No gauge reading
Water temp21.7°C
ClarityClear
Weather22°C
WindNE 10 km/h
Pressure1018 hPa
Rain · recent1.3 mm
Rain · ahead27.4 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 21.7°C — above the brown trout caution line (18°C). Fish dawn or dusk only. Land it fast, wet hands, no air shots. Otherwise very poor — water clarity is in the right range.
Sub-surface · on the nymphunder the surface

Hatch predictions

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Beyond the hatch · worth watchingambient prey

Hatch predictions

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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
Salmon runRun
1
2
2
2
2
2
1
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.
  • AAPPMA permits.
What's coming
Plan ahead
5-day outlook
Water here around 22°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
  1. Photo of Isole
    Isole — image via Wikipedia (Isole)
  2. Terrain map of the venue
    Terrain map
About this water

Tributary of the Ellé at Quimperlé described as a wild-trout paradise where Armorican granite creates clear, responsive water. Small stream requiring intimate casting and careful wading. Fly-fishing potential. Not crowded water — solitude and wild trout are part of the appeal. Spring through early autumn. Check AAPPMA for access and regulations.

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

WFD classification · FRGR0091

The full read · show the working · for brown trout · confidence 80%
How the 16 is built — score × weight = contribution
Temperature8 × 28%2.2
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time50 × 13%6.5
Pressure80 × 7%5.6
Insect activity55 × 12%6.6
Limiting factor: Water temperature (21.7°C) is outside Brown Trout's preferred range (10–16°C)= 56
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
  • Salmon1 March → 15 September
  • Trout2nd Saturday of March → 3rd Sunday of September

Salmon: Banned (2026) — Brittany 2026 order bans Atlantic salmon and sea trout on all Breton rivers.

Sea trout: Banned (2026) — Brittany 2026 order bans Atlantic salmon and sea trout on all Breton rivers.

Related guides
Pyrenees PlaybookFrench riversEuro Nymphingsubsurface methods
Booking & contacts