Skwala Stonefly Adult

The Skawla stonefly is also called the Spring Stonefly in many areas because it hatches in the spring, sometimes as early as December and as late as April. This hatch is often overlooked because it takes place early at the start of the season when some consider the water is too cold for good fly fishing. They are similar to Salmonflies in appearance and behavior; however, they are not as large as the Salmonflies. In fact, they actually are Little Yellow Stoneflies but they are larger and somewhat different from the Little Yellows. They are found in riffles and runs of the Rocky Mountains streams especially Rock Creek, Montana and the Yuba River in Washington.

They prefer clear, cold, fast water streams with gravel or stone bottoms; and they become active when the water reaches 40 degrees F. Hatches start when the water approaches about 50 degrees F.

After shedding their nymphal shucks on the rocks and banks, they fly to the vegetation on the banks to mate. The males do not have wings and consequently will not land in the water unless blown or fallen into the water. The females will fly out over the riffles and runs and dart down touching the water to deposit their eggs.