Blue Winged Olive

The Blue Wing Olive fly pattern imitates one of the most widespread and variable insects in American trout waters. “Blue-Winged Olive” is the common angler’s name for mayflies in the genus Baetis and several closely related groups—small, prolific insects found in rivers and streams across the country.
These mayflies are a cornerstone of a trout’s diet, hatching in a wide range of sizes and subtle color variations throughout the year. Because of this consistency, Blue Wing Olive patterns remain a dependable choice for anglers in every season.
The name comes from the adult mayfly’s appearance: slender bodies in shades of olive or dusky green paired with wings that often carry a soft bluish cast. Their abundance, adaptability, and year‑round presence make the BWO one of the most important insects to imitate in fly fishing.