Spate · Granite · West / Connemara, IE

Costello / Fermoyle

Coastal inlet near Costelloe Lodge in Connemara, County Galway, Ireland.

A distinct classic Connemara sea-trout system with its own literary pedigree — T.

Poor · Atlantic Salmon
Cascade · 10-14
Closed season
Out of season. File this water for the right month.
Closed — confidence not applicable today.
What moved it
  • LevelProxyvia Erriff
  • Water temp13.3°C
  • ClarityVery colouredColouring up
Today's fly
Cascade
Cascade10-14
From the river-specific salmon pack.
Conditions on the water
Proxy gauge
Level
Rising
Proxy
via Erriff
Water temp13.3°C
ClarityVery coloured
Weather15°C
WindSW 48 km/h
Pressure1002 hPa
Rain · recent5.0 mm
Rain · ahead31.4 mm

No gauge on this water — conditions are inferred from Erriff. The trend transfers, the absolute level does not.

Water temperature for Atlantic Salmon
Ideal
13°C est.ideal 10–16°C
0°14°28°
How to fish it · for Atlantic Salmon
When
All day is fishable. Peaks around mid-morning (10-12) and late afternoon (4-6pm). A change in light — cloud passing over the sun, or the first shadow reaching the water — can trigger a take.
Where
River still rising — fish the margins and slacker water where running fish pause. Avoid the main current. Eddies and backwaters behind boulders can hold fish temporarily.
Method
Medium-paced swing, fly fishing just below the surface. Fish are willing to move — a steady broadside presentation across the current is ideal. Vary speed through the swing.. Slow intermediate or light sink-tip. Small-medium: size 8-12 doubles, small tubes. Fish are willing to move — let them come to the fly.
Kit
13 ft #8/9 double-hander in spate, 10 ft #8 single in low water. Floating line plus a fast-sink tip. 12–15 lb fluoro tippet.
Why this works
Very few salmon are historically caught on this river in September (based on guide reports and fishery knowledge). Current conditions matter, but expectations should be modest. Conditions are reasonable, though not ideal. Late season — fish are beginning to colour up as spawning approaches. They become more territorial and can take aggressively. Autumnal colours (orange, copper, gold) work well.
Likely species
Stoneflies
Caddisflies
Hatch timeline · todayPeak at 2pm

Hatch predictions

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Sub-surface · on the nymphunder the surface

Hatch predictions

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Beyond the hatch · worth watchingambient prey(1)

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 · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Salmon runRun
1
2
2
2
2
2
2
1
Sea trout runRun
1
2
2
1
March BrownHatch
2
3
2
CapererHatch
2
3
3
2
Heather FlyHatch
2
2
Autumn DunHatch
2
3
2

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

Ranked for today
Atlantic Salmon fly box

Connemara/Mayo low water: a lightly-dressed shrimp on a floating line with sink tip, sized down from 8s in cold spring water to 12s and 14s as summer water warms and clears. Where the current runs faster, a slim tube or hairwing swung through tracks better than a shrimp.

Permits & access
Permit required — see local rules.
  • Costello & Fermoyle fishery — private, managed by IFI
  • Day tickets may be available
  • State rod licence required
  • Fly fishing only on the Costello and Fermoyle system; beats rotated and rod numbers strictly limited.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Owengowla
21 km
0
Brown trout · Salmon · Sea trout
Screebe / Gowla
12 km
Brown trout · Salmon · Sea trout
Invermore
15 km
Brown trout · Salmon · Sea trout
Gowla Lough
19 km
Sea trout · Salmon
Derryclare Lake
27 km
Brown trout · Sea trout
Gallery · 2
  1. Coastal inlet near Costelloe Lodge in Connemara, County Galway, Ireland.
    Coastal water near Costelloe Lodge, the heart of the Costello / Fermoyle fishery, County Galway.
  2. Terrain map of the venue
    Terrain map
About this water

A distinct classic Connemara sea-trout system with its own literary pedigree — T. C. Kingsmill Moore's Bumble tradition was born here — and still-credible current runs. IFI reporting notes improving sea-trout runs in 2025 after a slow start, and the 2023 season saw a big increase in sea-trout catches even when salmon were down. A chain of granite lakes connected by short river sections, draining through a brief tidal reach into Casla Bay. Fish move quickly through the system after rain; the sea-trout season runs 1 June to 30 September. Lake drifts with wet fly teams are the traditional method; river sections fish on the spate. Better-supported as a current sea-trout story than generic west-of-Ireland nostalgia, but still fundamentally water-responsive rather than calendar-reliable. For 2026 this remains an open fishery — salmon may be retained in season under the Wild Salmon & Sea Trout Tagging Scheme and bag limits, with catch-and-release at other times.

Hatches & food

EPA kick-sample monitoring of the Costello/Fermoyle system (2009-2018) confirms mayflies, stoneflies, caddis, midges and blackflies, and freshwater shrimp (Gammarus) are all present in the aquatic food base. This is presence evidence from monitored waterbody segments only, not a record of emergence timing, abundance, or a visible hatch on the water.

  • Lough system
  • Granite
Water quality (WFD)
  • Ecology: Good
  • Chemical: Unknown
What this classification means

EPA WFD 2019-2024 — Good ecological status; filled 2026-06-18. Source: EPA Ireland WFD 2019-2024 classification (catchments.ie / EDEN).

EPA (Ireland) · IEWE_31C080760

The full read · show the working · for Atlantic Salmon · confidence 75%
How the river scores — hydrology factors
Water heightHigh But Manageable+0.8
Recent riseClear Recent Rise+8.8
Falling after liftStill Rising Hard-0.6
Water temperatureCool To Moderate+3.5
Time in seasonLate Season+0.4
ClarityClearing+2.4
Hydrology base15.3
Rules that fired
Rise Plus Good Temp Bonus+0.75
Will they take?Willingcaps the band

Fish should be willing to take — clearing, stained water, fresh fish moving on the lift.

Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowproxy via Erriffproxy
What would change the calculation
No prolonged stable spell before the current rise.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Salmon 1 February → 30 September
  • Sea trout 1 June → 30 September

Sea trout: Variable seasonal (2026) — Costello / Fermoyle is one of the original Connemara fisheries documenting the 1989/1990 sea-trout collapse. IFI 2023–2025 evidence shows volatility — strong runs in some years, near-empty in others. Western fishery district catch-and-release / retention restrictions apply.

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Booking & contacts