Stoneflies
Caddisflies
- 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
Rules at a glance
- Permit required
- Fly only
Water temperature for Atlantic Salmon
Ideal13°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
Caddisflies
- Green SedgeMost likelyLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- Net-spinning caddisAlso possibleLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- Large sedgesAlso possibleNearest relative#8–10 · AdultBig waked sedge in the last light and after dark.
- CapererAlso possibleLower confidence#10–12 · AdultBig autumn sedge; fish dry at last light.
Hatch timeline · todayPeak at 14 Uhr
Hatch predictions
Today's headline hatch shown — see all 12 active hatches hour by hour as a supporter.
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Sub-surface · on the nymphunder the surface
Hatch predictions
Supporters see the full sub-surface read.
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Beyond the hatch · worth watchingambient prey(1)
Hatch predictions
Top prey shown — see all 3 as a supporter.
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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
Fly box · Atlantic Salmon
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
Gallery · 2
Coastal water near Costelloe Lodge, the heart of the Costello / Fermoyle fishery, County Galway. Terrain map
Water quality (WFD)
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
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.
Related guides
Casting instructors near here
Booking & contacts
Costello / Fermoyle
Water temperature for Atlantic Salmon
Ideal13°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
Caddisflies
- Green SedgeMost likelyLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- Net-spinning caddisAlso possibleLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- Large sedgesAlso possibleNearest relative#8–10 · AdultBig waked sedge in the last light and after dark.
- CapererAlso possibleLower confidence#10–12 · AdultBig autumn sedge; fish dry at last light.
Hatch timeline · todayPeak at 14 Uhr
Hatch predictions
Today's headline hatch shown — see all 12 active hatches hour by hour as a supporter.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Supporters see the full sub-surface read.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey(1)
Hatch predictions
Top prey shown — see all 3 as a supporter.
Start free trial14-day free trial. Cancel anytime.
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
Fly box · Atlantic Salmon
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
Gallery · 2
Coastal water near Costelloe Lodge, the heart of the Costello / Fermoyle fishery, County Galway. Terrain map
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
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.
Related guides
Casting instructors near here
Booking & contacts