The Blue-winged Olive is a small mayfly with olive-green body and slate-blue wings that is one of the most important hatch species for fly-fishing throughout the trout season. It is typically a multi-brooded species with emergences in spring and fall. Massive spinner falls of dying adults on the water surface create intense feeding activity among trout and other fish.
Habitat
Cold, clean streams and rivers throughout North America
Diet
Nymphs: algae, diatoms, and organic detritus. Adults: do not feed
How common
Common
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