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These are diverse, spiny-rayed freshwater fishes with ctenoid scales, thoracic pelvic fins, and usually barred rather than striped color patterns. They are distinguished by the possession of two separated dorsal fins, only 1 or 2 anal spines, and slender bodies. Darters possess striking pigment patterns, often with intense blue, green, or orange colors. Three groups make up this family: (1) the yellow perch in the genus Perca (Percinae); (2) walleye, sauger, and blue pike in the genus Sander (formerly Stizostedion; subfamily Luciopercinae); and (3) darters in the genera Percina, Ammocrypta, and Etheostoma (Etheostomatinae). Members of the first two groups are large, predaceous inhabitants of the Great Lakes and inland lakes as well as larger streams. Darters are small, and mostly stream dwellers, but a few are lake or pond fishes. The Percinae and Luciopercinae, each with just a few species, occur in Europe as well as eastern North America. The darters are exclusively eastern North American and there are at least 135 species of them. All members of this family spawn in the spring. The yellow perch lays a zigzag ribbon of eggs in moderately shallow water. The walleye and sauger scatter their eggs on the bottom in shoal areas; the blue pike frequented deeper waters in Lake Erie. The darters are diverse in their habits: (1) some, like the Iowa and least darters and logperch, leave eggs unguarded on the substrate; (2) others, such as the rainbow and orangethroat darters, bury their eggs in fine gravel on riffles and desert them; but (3) still others, for example the Johnny darter and the fantail, practice parental care--the males establish nests beneath flat stones or other objects on the bottom and courageously guard the eggs, which are laid on the ceiling of the breeding cavity. All are carnivorous and feed mostly on microscopic animals when young. With increasing size, aquatic insects and their larvae and a host of kinds of other invertebrates are eaten. Adult perch, walleye, and sauger eat other fishes, such as minnows. The yellow perch was an important food and sport fish throughout the southern part of the Great Lakes region. It was once an important part of the commercial catch and was taken in great numbers by anglers. It is active in the winter and may be taken through the ice. In the Great Lakes, walleyes attain greatest abundance in Lake Erie. They are also important in northern inland lakes and larger rivers. The sauger and bluepike were credited with being an increasingly important part of the commercial catch until the 1950s.
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