The mayfly is up, trout are biting and guesthouse beds are filling for miles around the western lakes, writes Lorna Siggins in Galway.
That's the word from the Western Regional Fisheries Board, which predicts that the ephemeral insect will once again generate millions of euro for the regional tourist economy.
Angling on loughs Mask, Corrib and Carra has been "very good" over the past couple of days, according to Mr Danny Goldrick of the fisheries board. He caught three fine trout himself on Carra several evenings back, and says the present overcast conditions are "ideal".
However, several over-enthusiastic anglers appear to be ignoring weather warnings. A party of anglers was forced to stay on the Corrib in gale conditions overnight and returned to safety yesterday.
Irish Water Safety has reminded all boat-users to wear lifejackets and to be aware of local weather forecasts before venturing on the water. Hundreds of anglers from the east coast and beyond tend to migrate west when the word is out and the fly is "up".
The graceful mayfly, so named because of the timing of its main hatch, leads a joyless sort of life. Its Latin scientific name, Ephemera, is even more appropriate. Mayflies spend up to three years as an egg and a nymph among mud and stones, feeding on debris on lake beds. When they mature, they rise to the surface during May to August. Their skin splits and a winged insect is released.
The "dun", as it is known by anglers, will moult again within hours and a "spinner" takes flight. The adult mayfly mates, sheds the eggs, and perishes within a day or two. As they fall onto the water's surface, the trout spots the disturbance and snaps. Some are also food for keen-eyed sand martins and swallows.
Mr Denis Kelleher, public relations officer for the World Cup Trout Fly Competition on Lough Mask, said the first signs of hatches on Lough Mask were evident at the weekend. "Ballinrobe will be packed out now for the next few weekends, and there won't be a bed anywhere," Mr Kelleher predicted.
"There are reasonable hatches of mayfly on Lough Corrib," Mr Goldrick said. "Lough Carra is the earliest of the western loughs to have mayfly hatches, usually starting the first week in May and continuing for a least a fortnight.
"Throughout the summer months, from just past the normal mayfly period, all of the western limestone loughs experience a sprinkling of mayfly, particularly Lough Mask where, under certain conditions, hatches can be quite strong."
Mr Kelleher said lifejackets would be compulsory during the World Cup competition on Lough Mask, which marks its 50th anniversary when it opens on July 31st. The contest normally attracts upwards of 700 anglers, he said.