THE COMBINED EFFECT OF TEMPERATURE 
AND DELAYED INITIAL FEEDING OF THE 
SURVIVAL AND GROWTH OF 
LARVAL STRIPED BASS 
Morone Saxatilis (WALBAUM) 
Bruce A. Rogers 
Graduate School of Oceanography 
University of Rhode Island 
Kingston, R.l. 02881 
Deborah T. Westin 
Graduate School of Oceanography 
University of Rhode Island 
Kingston, R.l. 02881 
ABSTRACT 
Rearing temperature and the time of first feeding interact to determine the 
degree of survival and rate of growth in larval striped bass. Between 15 and 
27°C, temperature affects the rate of growth and development in fed groups, 
and the time to death by starvation in unfed lots. Delayed first feeding retards 
structural development. The ‘point-of-no-return’ in striped bass is very near the 
stage of complete mortality due to starvation. Unfed groups survived up to 22 
days after hatching at 24°C and 32 days at 15°C. Larvae fed late into 
starvation survived and continued to grow at a rate somewhat higher than that 
observed in earlier fed groups at all temperatures. Larvae which has survived 
delayed development were indistinguishable on the basis of external 
morphology from much younger individuals reared under more favorable 
conditions. The effects of nutritional and thermally induced developmental 
retardation are discussed in terms of how they may affect larval growth and 
mortality rate estimates used in assessing the effects of estuarine power plants. 
INTRODUCTION 
Many estuarine and marine fish species, including the striped bass, Morone 
saxatilis (Walbaum), produce large numbers of relatively small pelagic eggs at 
spawning. These smaller eggs contain fewer yolk reserves. After a relatively 
short incubation period, they hatch into prolarvae that are, in general, at a 
more rudimentary stage of structural development than those of species 
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