Is This Fly A Dry Fly Or Nymph? — Fly Tying in 60 Seconds Fly fishing fly emerger patterns are designed to imitate insects as they transition from the nymph stage to the adult stage on the water's surface. Emergers are often considered one of the most effective patterns to use in fly fishing because they imitate vulnerable insects during a critical phase of their life cycle. These flies can be used when you observe insects hatching and emerging on the water. This PMD Emerger is perfect to use th