9521010 Lewis The utilization of estuarine habitats as nurseries by many coastal fishes is considered to be critical to the productivity and survival of those pmpulations, yet patterns of usage and an understanding of factors which effect differences in habitat utilization within and among estuaries by the larvae of these species are not well-defined. The objective of this planning study is to measure the physiological and behavioral responses of estuarine-dependent larval fishes (Atlantic menhaden Brevoortia tyrannus and spot Leiostomus xanthurus) to a range of salinity regimes. This preliminary information will provide a basis for designing more rigorous experiments that will relate larval growth and survival to environmental fluctuations. ***
