| Popis: |
Since 1990, 35 mm cameras have been mounted on Caribbean chevron traps used to sample reef fish in the South Atlantic Bight. These cameras were developed to photograph the habitat type associated with the trap. In instances where traps were recovered with no catch, the photograph was checked to determine if the trap had landed on sponge coral habitats, ledges, and rocky outcrops, commonly referred to as live bottom. If it had, the trap was considered a valid sample and incorporated into catch per unit effort (CPUE) calculations. This method of calculating CPUE was compared with that previously used in which all traps with zero catches were excluded from analyses, and a new method where all traps set were considered valid samples. Using a single factor ANOVA, no significant differences were found between CPUEs calculated using the three methods for the five most abundant species sampled. While trap cameras were useful in identifying live bottom habitat for sample sites where no historic bottom type data were available, they did not significantly impact the results of CPUE analyses when traps were set in the vicinity of previously identified sponge coral habitats. |
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