The main objective of this class experiment is to measure the activity of two metabolic enzymes in crude extract from bird pectoral muscle and to relate the differences to their mode of locomotion and ecology. The laboratory is adapted to stimulate the interest of wildlife management students to biochemistry. The enzymatic activities of cytochrome "c" oxidase and lactate dehydrogenase are measured in pectoral muscle of black duck and ring-necked pheasant. The black ducks have a high cytochrome "c" oxidase/lactate dehydrogenase (LDH) ratio, which reflects high aerobic capacity required for sustained and long distance flight. The low cytochrome "c" oxidase/LDH ratio in ring-necked pheasants and high level of LDH activity suggest that this bird can only support short bursts of flight, which may be related to his strategy of predator avoidance.