Aerobic Swimming Performance of Juvenile Largemouth Bronze Gudgeon (Coreius guichenoti) in the Yangtze River

Largemouth bronze gudgeon (Coreius guichenoti), a fish species once abundant in the Yangtze River, has been rapidly declining in recent years. One important factor, among many, is the interruption of the free-flowing rivers by dams. To obtain data that can be applied to the design of an effective fishway for C. guichenoti and other species in the fish community, a laboratory study of juvenile C. guichenoti's swimming ability and energetics was conducted in a flume-type respirometer equipped with a high-speed video camera system to record swimming behavior. The critical swimming speed (Ucrit), standard metabolic rate (SMR), and maximum metabolic rate (MO2,max) were determined during steady swimming at four water temperatures (10, 15, 20, and 25 degrees C). A power function accurately describes the relationship between oxygen consumption rate (MO2) and swimming speed (U) at the four temperatures. The Ucrit, SMR, MO2,max, and metabolic scope increased with increasing temperature. The relationship between cost of transport (COT) and U was characteristically inverse bell-shaped, with minimum COT at Uopt = 4.55.0 body lengths per second (bl sec-1). This investigation provides data on the swimming ability of C. guichenoti that will add to the basic science required for fishway design. J. Exp. Zool.317:294302, 2012. (c) 2012 Wiley Periodicals, Inc.