Caddis hatch for most of the summer, but some of my favorite times to match them are the heavy spring and early summer hatches in the Rocky Mountains. The Mother’s Day hatch of brachycentrus caddis on the Yellowstone River near Livingston, Montana is the most famous springtime emergence. But this early season caddis also can be found on other regional waters, such as the lower Henry’s Fork, Madison, Snake, Green, Clark Fork, Big Hole and Gallatin rivers among others. It’s also fairly widespread in Colorado. The Mother’s Day moniker is true on some waters, but the bulk of that activity takes place in late April. This timing coincides with the start of runoff and it is a mad race for the weather to get warm enough for the bugs to emerge, but not too warm to start spring runoff, which could make the rivers unfishable. The best way to hit these hatches is to live there, near the banks of those rivers, and be voluntarily unemployed. Most of us can’t do that and even if we could some years we’d hit the hatch for a couple weeks of prime fishing and other years we’d only get a few days. You hope for the best and take your shots when the
Another peak of caddis activity occurs around the tail end of runoff, usually around the end of June or the Fourth of July, depending on water conditions. At this time, a variety of caddis and small stoneflies can be found in abundance. The stoneflies shine during the day with caddis activity taking over as evening arrives. These early summer caddis are mostly hydroschye. They resemble a turkey quill in coloration. One of the best hydroschye hatches occurs on Montana’s Missouri River in July, a predictable evening emergence, usually right at dusk, that brings every fish in the river to the surface. On the Missouri, that means plenty of heavy 16-to 22-inch browns and rainbows.
On the Missouri, and the aforementioned streams, take advantage of situations when trout can feed heavily without expending much energy. The caddis hatch provides that—trout can rest on a seamline and watch a steady stream of caddis float over their heads. Because these mergers are struggling at the surface trout merely raise up, suck in a snack, drop down a few inches and repeat.