Early Brown Stonefly

Overview: The Early Brown Stonefly, also known as the Willowfly, is a small, cold-weather stonefly that emerges early in the fishing season, often as the first significant hatch of the year. Found in clear, fast-flowing streams and rivers, these insects are vital food sources for trout coming out of winter lethargy. Their subdued brown coloration blends with the environment, and their low-profile emergence creates opportunities for subtle fly presentations.

Nymph Stage: Nymphs of the Early Brown Stonefly are slim and range from 3/8 to 1/2 inch in length. They are dark brown with lighter banding and have strong, developed legs for clinging to submerged rocks in fast currents. Tied on hooks sized 12–16, nymph patterns are best presented with a dead drift near the riverbed. During pre-emergence, targeting shallower runs and riffles can yield success as nymphs migrate to the edges.

Adult Stage: Adults are about 3/8 to 1/2 inch long, with light to medium brown bodies and delicate, transparent wings. Fly patterns tied on hooks size 12–16 effectively imitate them. These adults are weak fliers and often skitter on the surface or rest on nearby vegetation. Fish dry patterns near the edges of streams and riffles, especially in the late morning and early afternoon when they are most active.