Lough Conn’s reputation as a fine brown trout and salmon fishery goes back to the very beginning of angling in the west of Ireland. There is a sizeable char population present. It is a big lough – about 14,000 acres – and measures 9 miles from north to south and varies in width from 2 to 4 miles. Conn is regarded as a very free-taking lough. It is a great favourite with those who like to fish traditional style in front of the boat and, because trout take the wet fly so freely, very little dapping takes place there – indeed, it is almost frowned upon. Conn is the first choice in the country for international matches – a measure of its reputation for producing fish. It is managed by the North-Western Regional Fisheries Board and its devotees are quick to boast that due to the healthy state of the wild trout stocks it has never been stocked with trout or fish of any kind. It is well served by roads all round and an angler can easily lauch a boat at more than half a dozen locations. There is access to the lough at Gortnorabbey Pier near Crossmolina, Errew Pier, Phiulawakhouse Bay, Gillaroo Bay, Pontoon, Knockmore Bay, Brackwansha, Sandy Bay and Cloghans Bay.
Salmon are taken mainly by trolling from the end of March to July and the best areas to concentrate on are the northern end of the lough, Cornakillew, Massbrook and Castlehill Bay. Trout anglers frequently take salmon on the fly in June and July. About 600 fish are taken annually. The trout fishing begins to pick up in April and reaches its climax with the mayfly hatch in late may and June. The wet-fly fishing can be very good from late August to the end of the season. The artificial flies that work best can be divided into three groups, depending on the time of year: in the early season, Fiery Brown, March Brown, Connemara Black, Bibio, Sooty Olive, (best of all), Black Pennell, Peacock Spider, Glden Olive, Green Olive, Mallard and Claret, Blae and Black; in the mayfly season, artificial Mayfies, Green Peter, Teal and Yellow, Invicta, Bumble lice, Cock Robin, Bibio, Claret Bumble and Watson’s Fancy; and, after the mayfly all the sedge patterns (Green Peters, Murroughs, etc), Sooty Olive, Bibio, Bumble Olive, Peacock Spider, Coch-y-bondhu, Watson’s Fancy, Black Pennell, Green Olive, Invicta and Connemara Black. These can all be dressed on size 8, 10 and 12 hooks, with size 10 the most popular. The shallows are all well marked with iron bars and the best fishing areas are along the shores, in the shallow bays and on the shallows out in the middle.
The season runs from 1 February to 30 September for salmon and from 15 February to 10 October for trout, with a 10-inch size limit. Conn is a well managed and exciting lough to fish, one where the visiting angler can always be sure of a welcome and good advice from the local anglers. There are plenty of boats and outboards for hire and even some professional boatmen. Boat, outboards and boatmen can be arranged through many of the hotels and guest houses around the lough.
Excerpts taken from "Trout & Salmon Rivers of Ireland, an angler's guide" by Peter O'Reilly.