Blue Wing Olive (BWO)
Adult coloration
Yellow
Olive
Light Gray
Active water temp
38-56°F
Description
Overview
The Blue Wing Olive (BWO), genus Baetis, is a small mayfly (order Ephemeroptera) common to freshwater streams and rivers, named for its olive wings with a bluish cast. It produces multiple generations a year, hatching heaviest on overcast days from early spring through fall, and is a steady trout food source throughout that stretch.
Nymph
BWO nymphs run 0.5 to 0.75 inches, olive to light brown with a darker thorax. They're active swimmers, working riffles and current seams among rocks and vegetation rather than clinging in place. Typical hook sizes: 16 to 20.
Dry/Dun/Spinner
The dun measures 0.5 to 0.75 inches, with an olive to yellowish-brown body and olive wings tinted blue. Hatches run dense on cloudy or drizzly days, when duns linger on the water and trout key in hard. Hook sizes run 16 to 22; parachute and thorax patterns work best.
Curated by the IdentaFly fly fishing team.
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