Spate · Granite · West / South Mayo, IE

Carrowniskey

Carrowniskey terrain map

A short south Mayo spate river running off the slopes of Croagh Patrick and the Sheeffry Hills to the sea near Louisburgh.

Poor · Atlantic Salmon
Collie Dog · 6–10
Closed season
Out of season. File this water for the right month.
Closed — confidence not applicable today.
What moved it
  • LevelProxyvia Erriff
  • Water temp5.5°C
  • ClarityClear
Today's fly
Collie Dog
Collie Dog6–10
Regional salmon default — river-specific evidence is thin.
Conditions on the water
Proxy gauge
Level
Steady
Proxy
via Erriff
Water temp5.5°C
ClarityClear
Weather8°C
WindS 28 km/h
Pressure1008 hPa
Rain · recent0.4 mm
Rain · ahead4.3 mm

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

Water temperature for Atlantic Salmon
Cool — slow
6°C est.ideal 10–16°C
0°14°28°
How to fish it · for Atlantic Salmon
When
Morning into early afternoon.
Where
Pool tails, steadier runs, and any water with pace.
Method
Fish a sensible line-and-fly combination for the height and pace of water.
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.
Likely species
Stoneflies
Gammarids
Hatch timeline · todayPeak at 11am

Hatch predictions

Today's headline hatch shown — see all 4 active hatches hour by hour as a supporter.

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Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 3 guilds as a supporter.

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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 · November highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Salmon runRun
1
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.
  • Western district
  • IFI managed in part; part of the river held privately by the Harman family
  • Shrimp (natural and artificial) is prohibited
  • State rod licence required.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Bunowen River (Louisburgh)
6.0 km
0
Brown trout · Salmon · Sea trout
Delphi Lodge
15 km
0
Salmon · Sea trout
Culfin River
15 km
0
Salmon · Sea trout · Brown trout
Bunowen River (Louisburgh)
6.0 km
Brown trout · Salmon · Sea trout
Lough Muck
16 km
Brown trout · Sea trout · Salmon
About this water

Part of the Ballinakill coastal district. Sea trout and grilse enter on the summer spates; the river dries to a trickle in July drought. Roonagh Lough, on the system, also offers fishing for both species when conditions allow. Part of the river is held privately by the Harman family; the rest is club and IFI water with day permits available locally. The setting is exceptional — the reek of Croagh Patrick above, Clew Bay below — but the fishing demands water. Given the right conditions, fish move fast through the system and are fresh. A river to visit opportunistically rather than plan a trip around, but one worth knowing for its quality when conditions align. For 2026 this is a catch-and-release fishery under the Wild Salmon & Sea Trout Tagging Scheme — all salmon and grilse must be returned.

Hatches & food

EPA monitoring confirms mayflies, stoneflies, caddis, aquatic diptera and gammarus are present across the Carrowniskey's WFD reaches. This is food-presence evidence from kick sampling only, with no confirmed emergence timing or dependable hatch.

  • Granite
Water quality (WFD)
  • Ecology: Unknown
  • Chemical: Unknown
Why this score · for Atlantic Salmon
  • Temperature1330% weight
  • Flow6025% weight
  • Clarity9520% weight
  • Feeding Time4015% weight
  • Pressure8510% weight
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Salmon 1 April → 30 SeptemberC&R
  • Sea trout 1 June → 30 September

Sea trout: Variable seasonal (2026)

Related guides
Atlantic Salmonsalmon tacticsIrish Salmon Rivers Guidefive great salmon fisheriesConnemaraIrish fishing
Casting instructors near here
Booking & contacts
At a glance

Carrowniskey is a spate river in West / South Mayo, Ireland. The catchment geology is recorded as granite, and the water sits at about 8 m above sea level. The river is described as roughly 12 km long. Species listed for this water: brown trout, salmon and sea trout. It is classed as a salmon river. The salmon season is recorded as running from 1 April to 30 September. The sea trout season is recorded as running from 1 June to 30 September. Best window recorded for anglers: June–September; best on rising or early dropping water. Core methods listed: across and down on floating line; spate fishing immediately after rain. Nearby waters in our listings include Bunowen River (Louisburgh) at 6.0 km, Bunowen River (Louisburgh) at 6.0 km and Delphi Lodge at 15 km.