Midge flies are small, slender flies that are often found in the colder months. They are a favorite food of many fish, including trout, and can be a very effective bait in the winter. One of the key techniques for success when fly fishing with midges is to use a midge cluster pattern. A midge cluster is a group of midges tied together on a single hook, creating a more realistic and attractive bait for fish. These flies mimic a group of midges mating or hatching at the same time, and are often effective at attracting fish when nothing else seems to be working.