For many of us the month of March marks the beginning of an emergence from the cold, dark days of winter. Here in Montana there is little exception to that. In March, Montanans will gain almost 2 hours of daylight. In other words, the days will be close to 2 hours longer at the end of the month, than at the beginning. Most of us will notice this seasonal change, as will the trout and the insects they consume.
As water and air temperatures begin to rise throughout the spring and into summer, different species of bugs will reach their "critical point" where air temperature, water temperature, and other conditions are just right for them to hatch. Warming water this time of year also brings water temperatures into a range where trout are most active. This combination of active fish and active insects is a great recipe for consistent action on our rivers. These next 4 months(March-June) will provide the widest variety of bugs and some of the best dry fly fishing that we see in Montana all year. Blue-winged Olives, an assortment of Caddis, March Browns, PMD's, Yellow Sallies, Golden Stones, and Salmonflies will all hatch at some point between now and the end of June.
One of the things I most look forward to in Spring are the thick hatches of Blue-winged Olives that frequent such fisheries as: The Yellowstone, Madison, Gallatin, Bighorn and Missouri rivers. Our region's famous, spring-fed creeks(Depuy's, Nelson's, Armstrong), can offer some exceptional small stream, technical, "match the hatch", style fishing too. Perhaps this video, shot last spring on the Lower Madison can better illustrate what these experieces can be like.