The growth and abundance of yellow perch Perca flavescens in Saginaw Bay have varied historically. Changes in growth have been ascribed to many causes, including density and genetic composition of the fish stock, both of which are also believed to vary with location in the bay. The objectives of this study were to compare growth and maturation of yellow perch from inner and outer Saginaw Bay, to investigate the existence of different fish stocks, and to compare growth of yellow perch in Saginaw Bay to growth in other locations to determine the degree of stunting. Yellow perch were collected from four sites in inner and outer Saginaw Bay from 1983 to 1985. Size distributions differed between the inner and outer bay sites: larger and older fish were more common in the outer bay. Percentage of body water, body energy density, gonadosomatic index, and age at maturation did not differ between the inner and outer bay sites. Growth in weight, total body energy, and condition factors differed significantly. These results indicate that growth conditions differ between the inner and outer bay, but the fish populations may not be isolated completely, as has been suggested. Results also suggest that the growth differential has not caused large geographic differences in growth rate, but has caused small condition differences. Yellow perch growth is poor in Saginaw Bay, and the fish appear unable to store substantial energy reserves at any time of year. It appears that behavioral differences between young and old fish may cause the differential distribution of fish by size in Saginaw Bay.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142193/1/tafs0976.pd
