Serratella (Ephemerella) ignita - Blue-winged Olive

The blue-winged olive nymphs are moss creepers and of limited importance to anglers because of their habit of crawling within dense mosses or resting under stones where trout cannot easily find them.

Dun

BWO dun - male

The duns hatch from mid morning until late afternoon, and are most abundant in June, July and early August.

Spinner

BWO spinner - female

The sherry spinner, the female spinner of the blue-winged olive, is seen here with her green ball of eggs. This is a very important fly on the rivers of Wales, and particularly dense hatches occur on the Teifi, the Usk and the Wye.

Fishing tip

On spate rivers, sherry spinners tend to congregate above the rapid waters between pools. There they swarm just before egg laying, and trout take up station either on the lip of the pool or at the head of the next pool downstream. A dry Sherry Spinner fished in such locations often tempts some very fine trout at dusk.