Mayflies
The Finn is the largest tributary of the Foyle system, rising in the Blue Stack Mountains of Donegal and flowing east to join the Mourne at Strabane. A powerful spate river with excellent salmon and sea trout. The river has both Republic (upper) and Northern Ireland (lower) sections — the Loughs Agency manages the fishery across the border. Salmon run from March with grilse from June. Sea trout from May. One of the most productive salmon rivers in the Foyle system. Day permits from Loughs Agency. Atlantic salmon are managed under DAERA and Loughs Agency conservation byelaws, with mandatory catch-and-release on many waters; check current rules before fishing.
No venue-specific hatch data yet; as a spate river of this basalt-and-peat country, expect flood-driven stonefly and terrestrial food to dominate over any steady upwing hatch — treat this as general guidance, not an observed hatch.
Summer-autumn runs, seasonal patterns vary by region
- Mixed
