📍Mayo · West📐10.19 km²📋IFI (Republic of Ireland)Season Open
4Species Present
Lough Cullin is a 10.19 km² shallow lake west of Foxford, County Mayo, connected to Lough Conn by a narrow inlet at Pontoon and draining directly into the River Moy. It reaches a maximum depth of approximately 3 m and sits within the River Moy SAC, historically regarded as one of Ireland''s premier brown trout fisheries and an important passage water for salmon bound for Lough Conn.
County
Mayo
Region
West
Type
Lough
Surface area
10.19 km²
Maximum depth
3 m
Nearest towns
Foxford
River system
River Moy
Species
Brown Trout, Atlantic Salmon, Pike, Roach
Lough Cullin sits in the shadow of its famous neighbour Lough Conn, connected to it by the narrow channel at Pontoon Bridge — but anglers who know it well would not trade it for anywhere else on a May morning when the mayfly are dancing over limestone-fed shallows. It is a lough with its own quiet character, less celebrated than Conn but in no way lesser for it.
The lough covers around 1,019 hectares in north Mayo, relatively shallow and fertile, sitting within the same limestone geology that gives the Conn/Cullin system its exceptional trout fishing. It drains southward through the outflow near Foxford and into the upper Moy system, giving it a role in the wider catchment that runs to Killala Bay.
Brown trout are the primary quarry. The mayfly season, typically beginning around mid-May, brings the finest dry fly sport, though wet fly fishing from late March through mid-June produces consistent results on drifts across the limestone shallows. Fish tend to run somewhat smaller than the best Conn trout, but they are in excellent condition and fight hard in cold, clear water.
Salmon pass through Cullin on their way to spawning grounds upriver, and while stocks have declined across the west in recent decades, some fish are encountered during summer months, particularly near the Pontoon inflow. Pike inhabit the margins and weed-fringed bays, providing sport for those who seek them, particularly from late summer into autumn.
Drifting is the traditional and most effective method — standard lough-style wet fly tactics with a team of three, covering ground from the Pontoon inflow southward with a westerly or south-westerly breeze. The weed growth that builds from mid-June limits access to some areas but also creates ideal habitat for larger fish. Local knowledge of the clean ground makes a real difference.
No permit is required to fish for brown trout on Lough Cullin, which makes it one of the most accessible wild trout fisheries in the west of Ireland. Pontoon village, perched between Cullin and Conn, offers accommodation and is a natural base for anyone wishing to fish both loughs across a week.
Salmon: 17 Mar – 10 Oct
Brown Trout: 15 Feb – 12 Oct
Pike: Year-round
Best times
Mayfly Season · Free Brown Trout Fishery · Limestone Lough · Pontoon Bridge · Lough Conn Connection
Difficulty
Intermediate
Access & bases
Lough Cullin is accessed from the N26 between Foxford and Castlebar. The main access point is Pontoon village, where the bridge between Cullin and Conn provides boat hire and bank access. A second access point exists at the southern end near Foxford. Parking is available at both points. Boat hire is available through Pontoon Bridge Hotel.
Season by season
March–April
Early season wet fly fishing on cold, bright days can produce trout on drifts across the cleaner ground in the centre of the lough. April shows particularly good potential with 50% positive reports and catch rates averaging 4.4 fish per rod. Fish are in good spring condition and sport, though patchy, can be excellent when conditions align. Duckfly hatches are prominent (mentioned in 12 of 29 early season reports), with buzzer activity beginning in late April. Evening rises sometimes occur on mild April evenings. Dabbler patterns are particularly effective, with Fiery Brown Dabbler being the top early-season pattern.
May (Mayfly)
The peak of the Cullin season with 59% positive reports and an average catch rate of 2.7 fish per rod. The mayfly hatch typically begins around 15 May, with the main hatch lasting two to three weeks. Mayfly activity dominates (mentioned in 21 of 32 May reports), with olive hatches also significant. Dapping with a live or artificial mayfly is the traditional method. Dry fly on floating line produces fish rising confidently in the surface film. Green Peter and Grey Wulff patterns are highly effective alongside traditional mayfly patterns. This window attracts visiting anglers and local regulars alike — book boats early. Castlehill Bay, Victoria Bay, and the Pontoon area are key productive zones.
June–October
Sedge and daddy longlegs patterns come into their own from late June. June maintains good quality with 54% positive reports and 3.3 fish per rod, while later summer becomes more challenging (July drops to 29% positive). Caenis hatches appear in June, followed by sedge activity from August. Weed growth complicates the fishing from mid-summer, but the clean drifts along the western shore and near Pontoon remain productive. Daddy longlegs patterns become effective from July onwards. Autumn brings improving conditions as temperatures fall, and back-end wet fly fishing can be excellent in a good blow.
Best conditions
Based on analysis of 119 IFI reports (2011–2025):
💨
W F3
Best wind
35% positive
☁️
Partly cloudy (30-60%)
Best sky
60% positive
🌡️
8-10°C
Best air temp
67% positive
⏰
10am–3pm during mayfly; evening sedge rises in June–August
Best window
Seasonal fly & tactics guide
Pre-Mayfly (March–14 May)
Patterns
BibioSooty OliveBlack PennellClaret BumbleConnemara BlackFiery Brown DabblerClaret DabblerSooty Olive DabblerPeter Ross DabblerBuzzerDry Olive
Standard lough-style wet fly fishing on a three-fly cast, size 10–12 early season moving to 12–14 as water warms. Fish the wave, covering ground on drifts over cleaner limestone ground. A brisk drift in a good wave is usually more productive than a slow plod. Target Cloghans Bay in early season for best results.
⚠️Common mistake: Fishing too large a fly in cold early-season water. Small, dark wet flies on size 12–14 hooks outperform larger offerings when the water is below 10°C.
Mayfly (c.15 May–end May)
Patterns
Green Drake (dry)Spent GnatGrey WulffYellow HumpyGreen PeterGinger DabblerOliveYellow Wulff
Dapping
Mayfly
Watch the surface carefully and position the boat to drift through rising fish. Dapping with a live or foam mayfly on a light dapping line is the traditional method and effective. Dry fly on a greased floating line for a more precise approach. Begin watching for rises from mid-morning. Focus on Castlehill Bay, Victoria Bay, and the Pontoon area where mayfly activity is most concentrated.
⚠️Common mistake: Starting too late. The best mayfly rises often occur before midday, particularly on calm, overcast mornings.
Fish the weed edges and the clean ground between weed beds. Sedge patterns fished in the surface film work well in the evening from August onwards. Daddy longlegs dapping is effective from late August through September. Caenis hatches provide opportunities in June.
⚠️Common mistake: Ignoring Cullin from mid-June because of weed. The clean drifts near Pontoon and along the western shore remain fishable all season.
What works here
Flies and methods reported most successful by the community.
Where to Fish at Lough Cullin
Pontoon Bridge
The inflow from Lough Conn at Pontoon creates water movement and draws fish throughout the season. Drifts starting near the bridge and running south with a westerly breeze are consistently productive. The Pontoon area is particularly effective during the mayfly season, being mentioned specifically in successful reports from May and June.
Western Shore
The western shore offers cleaner ground and good drifts with the prevailing south-westerly winds. The primary fishing ground for most visiting anglers. Cloghans Bay along this shore produces fish in both early season (March-April) and during the mayfly period.
Southern Outflow (Foxford End)
The outflow end of the lough near Foxford provides an alternative access point and a productive area, particularly for salmon moving through in summer. Castlehill Bay and Victoria Bay in this area are noted mayfly season hotspots.
Conservation & stewardship
🌿
Lough Cullin is a free, wild brown trout fishery that receives less angling pressure than many comparable loughs in the west. Practise careful catch and release, particularly for salmon, and handle all fish with wet hands.
Frequently asked questions
Before You Go — Key Regulations
Jurisdiction
Republic of Ireland (IFI)
Season
March 17 – October 10
Licence required
Yes — State Salmon Rod Licence
No permit is required to fish for brown trout on Lough Cullin. A state salmon rod licence (available from IFI at fishinginireland.info) is required for anyone targeting salmon.
Main access: Local boatmen available in Pontoon village; Pontoon Bridge Hotel can advise on guides, Pontoon Bridge Hotel, Pontoon, Co. Mayo — boat hire and accommodation, IFI North Western Region
