Flies are tied in the sizes, colors and patterns that best match local terrestrial and aquatic insects, baitfish, or other prey attractive to the type of fish you're trying to catch. In other words, you "match the hatch." Flies used in fly fishing imitate both the immature and adult stages of insects, as well as baitfish, leeches and worms.

Basic Fly Groups

Most flies fit into three categories: 

Dry flies: float on the water's surface and imitate a wide range of foods, including adult mayflies, caddisflies, midges, grasshoppers, crickets and ants. Seeing a trout, bass or panfish take a dry fly floating on the water's surface is one of the greatest sights in fly fishing.

Nymphs (sometimes called "wet flies"): represent the immature life stages of insects such as mayflies and caddisflies, and are fished below the water's surface. Some special nymphs, called emergers, imitate the emerging adult insect and are fished just below or in the water's surface film.

Streamers: represent minnows, leeches and other swimming food items that provide meals for bass, trout, panfish and saltwater fish such as tarpon, redfish, bonefish and striped bass. Streamers are known for their ability to take the largest fish in streams, ponds, lakes and saltwater.