ABSTRACT: Surf zone fishes were captured by beach seine over the late summer and early fall of 5 yr (1995 to 1999), spanning pre-, during, and post-nourishment time periods along a 15 km expanse of the New Jersey shoreline. During the baseline years of sampling, silversides (primarily Menidia menidia) numerically dominated the surf-zone fish community. In 1997, coincident with beach nourishment operations, bluefish Pomatomus saltatrix became numerically dominant, increasing in abundance 10-fold. Bluefish were not captured near active beach nourishment sites and were significantly more abundant at reference stations than in the beach nourishment (treatment) area for 2 of 6 sampling dates in 1997. In contrast, northern kingfish Menticirrhus saxatilis were more abundant at treatment stations in 1997, and on one occasion congregated at the stations undergoing active sand replenishment. The feeding habits of Atlantic silversides and northern kingfish were consistent throughout the study period. In 1997, prey biomass was greater in fish caught at treatment stations when significant differences occurred. Prey consisted primarily of benthic invertebrates such as polychaetes and mole crabs. Amphipods and insects, which probably originated from groins and terrestrial sources respectively, were also common prey items and were present in plankton samples. Retrospective power analysis indicates that an approximate 3-fold difference in mean fish abundance was the minimum detectable effect size between reference and treatment areas. Beach nourishment impacts on the surf zone fish monitored in this study were restricted to localized attraction (northern kingfish) and avoidance (bluefish) responses to the beach nourishment operation.
KEY WORDS: Beach seine · Dredging · Filling · Bluefish · Kingfish · Silversides · Power analysis · Turbidity · Fish food habits
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