EFFECTS OF TEMPERATURE, SALINITY, AND FISH SIZE ON GROWTH AND CONSUMPTION OF JUVENILE BLUEFISH

Consumption and growth rates of juvenile bluefish Pomatotomus saltarix increased with increasing temperature and decreased with increasing f ish size in short-term (7 days) experiments. Salinity had no effect on growth or consumption rate in a short-term experiment. In a long-term (90 days) mesocosm experiment, consumption and growth rates declined with increasing body size. Predictive equations developed from short-t erm experiments did not adequately predict observed consumption rates in the mesocosm experiment. However, growth in the mesocosm experiment was similar to field growth. Also, mesocosm consumption rates and con sumption rates calculated using field growth and mesocosm growth effic iencies were similar to published independent field estimates of consu mption rate. Our results indicate that experiments to determine the ef fects of temperature and the allometry of body size on growth and cons umption rates should be conducted over long time periods simulating fi eld conditions. Juvenile bluefish have rapid growth and their individu al cumulative consumption is large. This result suggests that bluefish may have a large effect on their prey populations. This effect has ye t to be quantified. (C) 1995 The Fisheries Society of the British Isle s.