Abstract

Fishery-independent surveys provide a means to acquire standardized abundance and diversity data that are ade-quately replicated over time and space. The standardization of these surveys control gear and/or sample-related varia-bility which allows researchers to assess the impact of seasonality, habitat, and a variety of other factors that affect abundance fluctuations of fisheries species. Following the Southeastern Area Monitoring and Assessment Program (SEAMAP) protocol we recently implemented a vertical longline (VLL) survey for demersal fishes inhabiting artificial reefs of the Texas coast. These reefs are dominated by cutoff and toppled oil and gas platforms which vary in complexi-ty, size, water depth and distance from shore. Three hook sizes (15/0, 11/0 and 8/0) were used to sample reefs varying between 30 and 60 m total depth. A subset of the deployments was accompanied by a GoPro© camera to supplement catch data with visual estimates of abundance, depredation events, and escapes. Neither hook size nor drop order af-fected the number of fish captured or seen, suggesting there was no enhanced baiting by larger gear or prolonged de-ployment times. The abundance and diversity of catch per deployment was not affected by the addition of the GoPro© camera. Preliminary results show a positive correlation between fish size (total length and weight) and hook size while diversity decreases as hook size increases. Our findings indicate that vertical longline surveys are a valid assessment tool for estimating fish abundance on Texas artificial reefs. However, as has been demonstrated elsewhere, VLL gear tends to target Red Snapper.

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