Fine-scale movements and home ranges of red snapper Lutjanus campechanus around artificial reefs in the northern Gulf of Mexico

Abstract

Few studies have examined fine-scale movement patterns of continental shelf marine fishes. For example, little is known about an important marine species, red snapper Lutjanus campechanus, and its fine-scale movement patterns around artificial reefs. Such information could provide insight on habitat use and help answer persistent questions concerning the ecological function of these structures for red snapper. Thus, the present study examined fine-scale movements (~1 m accuracy) of red snapper (N = 5) around artificial reefs in the northern Gulf of Mexico with the VR2W Positioning System (VPS, Vemco Ltd, Nova Scotia). This system enabled the continuous monitoring of tagged fish over extended durations (44–326 d) on various temporal scales (hourly, daily, and monthly). Red snapper showed a consistent close association with artificial reefs (mean ± SD distance = 19.3 ± 21.6 m). Home ranges (95% kernel density estimates, KDE) were significantly larger during daytime than nighttime periods. Monthly home ranges and core areas (50% KDE) were significantly larger in summer than in winter and positively correlated with changes in water temperature, suggesting colder temperatures reduced red snapper movement. Red snapper showed a high degree of site fidelity to the studied artificial reefs on multiple temporal scales, and these habitats provided a “home base” from which fish expanded area use to the immediately surrounding unstructured habitat.