Guelph Lake is popular for fishing yellow perch and pike. In the absence of alewives, walleye and yellow perch reproductive success greatly increased. Fishing offers trout, catfish, largemouth and smallmouth bass or yellow perch. Lakes and rivers are well populated with walleye, northern pike and yellow perch. The caudal fin of the yellow perch is forked. Lake whitefish and yellow perch are caught commercially. Largemouth bass, yellow perch and bluegills are common. Primarily, age and body size determine the diets of yellow perch. Common game fish include warm water fish such as crappie, bass, yellow perch, and bluegill. Total annual mortality of adult yellow perch has not changed since cormorant colonization. The nape, breast, and belly of yellow perch are all fully scaled. Yellow perch have many fine and sharp teeth. The cormorants specifically target yellow perch as primary prey. Yellow bullheads, yellow perch, and redear sunfish can also be found. The rate of PCB metabolism was temperature dependent in yellow perch ("Perca flavescens").