Emergers Flies are an import part of a fish’s diet. The insect is high up in the water column, exposed without the ability to escape….easy target! Emergers represent insects as the emerge from the bottom of the water to the surface - as they emerge they are vulnerable to fish. Common mergers are Caddis Flies, May Flies and Midges. Match the hatch correctly and you're going to have a field day with emerger flies.