Members of the Chironomidae species can range in size from the huge #l2 midges on Hebgen Lake to the tiny #26 green midges successfully fished on the Yellowstone River.

Midges are most important during their emergence, when fish rise to pupae and crippled adults. On some waters mating clusters can also be important. Because they emerge year-round, you must be prepared to fish midges at all times. The actual presence of midges on the water is the best clue that trout are rising to them.

Lakes, ponds, and sloughs are rich with midges, which are near the top of the list of insects that rising trout might be feeding on. On streams the importance of midges usually varies with the season. The summer months bring on caddis, mayflies, and stoneflies, moving midges to near the bottom of the list of favored trout insects.

From late fall into the spring season, however, midges may be the only aquatic insect emerging. Midges are two-winged flies that come in a variety of sizes and colors. They can emerge on all waters any time of the day and season. Be prepared with imitations of pupae and crippled adults and you will catch trout on midges.

Good fly patterns for midges are #10-26 Fur Midge Pupae, Serendipities, Zelon Midge Emergers, Cooper Bugs, Zelon Midges, Midge Clumps, and Griffith's Gnats. - Western Fly Fishing Strategies

Grasshopper activity is strongest during the heat of the sum' mer months, but I've taken trout from May through November on hopper patterns. Though hoppers are most prevalent in August and September, the fact is that they're often present on western waters for much longer. Grasshoppers are like tiny armored cars, burrowing in for several days to withstand snow and cold and appearing on stream again once the weather warms. Only a blanket of snow and cold of several days' duration will kill them.

Swarming bees and flying ants can bring tremendous rises of trout in Yellowstone country, especially in late July and August— though approaching a rise might be a bit unnerving with all the naturals buzzing about!

Flying ant swarms always bring rising trout on the Madison and Gallatin Rivers, several spring creeks, and some area lakes during mid-August.

The migrating Mormon cricket causes quite a stir on many waters during years when populations are strong. The females measure 2 to 3 inches long, and as they migrate across meadow areas many find their way into the water. I've heard reports of migrations during which a lead cricket jumped into the water and the others followed like lemmings. August and September are the best months for the cricket, although I've had fine action during June and October, too.

Be prepared for terrestrials whenever and wherever you are fishing western waters. This type of dry-fly angling can bring up the largest wild trout, and those who are ready for it can expect to do well - Western Fly Fishing Strategies