Percina caprodes

Logperches have two dorsal fins (located on the back; front one is spiny, rear one is soft), large rounded pectoral fins (located near the gill cover), two spines in the anal fin (located on the underside of the body just forward of the tail fin, and used in stabilization while swimming), and scutes (enlarged scales) on the breast (and on the midline of the belly of males). Scales are absent on the top of the head. Color is yellow-brown on the upper side, with many alternating long and short dark bars on the side that extend over the back and join those on the other side; the bars are relatively uniform and are not constricted in the middle. A dusky vertical bar extends below the eye. During the breeding season, the male's yellowish color becomes more intense, and males also develop small, fleshy projections, called tubercles, on the belly and the underside of the fleshy part of the tail. Maximum length is around 7.2 inches (18 cm).

Range includes the St. Lawrence-Great Lakes, Hudson Bay, and Mississippi River basins from eastern Quebec to Saskatchewan and south to the Gulf of Mexico. This species also occupies Atlantic Slope drainages (where rare) from the Hudson River, New York, to the Potomac River, Maryland, and Gulf Slope drainages from the Choctawhatchee River, Alabama and Florida, to the Mississippi River, Louisiana. It was recently found in the Churchill River system in Labrador. Logperches have been introduced in a few places in the Great Plains. Populations in the Mobile basin formerly assigned to P. caprodes are now recognized as P. kathae, and populations in the Meramec River and southern tributaries of the Missouri River in Missouri and Kansas and the Arkansas River system in Arkansas, Missouri, Kansas, and Oklahoma are now recognized as P. fulvitaenia.

Habitat ranges from small creeks to rivers, and also includes deep waters of lakes and reservoirs. In streams, this species prefers clean riffles and runs over substrates of mixed sand and gravel. It is often associated with bottom debris. In preparation for spawning, logperches move from deeper water to shallows. Eggs are laid in sand in lake shallows, or in gravel or sand in swift current, often in riffles, in streams. Young logperches may be found in dense beds of vegetation.

Spawning occurs mid-March to mid-May in the southern part of the range but not until mid-June to late July in northern Michigan. When spawning, a few to several hundred males gather in schools. Females enter the schools, and male and female pairs partially bury themselves in the sand and extrude and fertilize the eggs. Males are not territorial and do not guard the eggs. Eggs hatch in 5-8 days, depending on water temperature. At night, these fishes generally are inactive on the bottom.