Fine-Scale Movements and Home Ranges Of Red Snapper Lutjanus Campechanus Around Artificial Reefs In The Northern Gulf of Mexico

Few studies have examined fine-scale movement patterns of continental shelf marine fishes.  For example, little is known about the fine-scale movement patterns of red snapper Lutjanus campechanus, around artificial reefs in the northern Gulf of Mexico. The present study examined fine-scale (~1 m accuracy) movements of red snapper (N = 17) with the VR2W Positioning System (VPS, Vemco Ltd, Nova Scotia).  This system enabled the continuous monitoring of tagged fish over extended durations (100–694 d) with locations recorded approximately every 10 min, for over 1.9 million accurate locations of red snapper from Aug 2010 through June 2012.   Red snapper showed close association with the reef structure (mean ± SD distance = 26.3 ± 35.4 m), but differential habitat use patterns in relation to both diel and seasonal periods.  Home range areas (95% kernel density estimates, KDE) were significantly larger during day than night periods, and showed the lowest area use at dawn and dusk.  Monthly home ranges ( 95% KDE) and core areas (50% KDE) were significantly larger in spring, summer, and fall than winter, and significantly correlated with water temperature, suggesting colder winter temperatures reduced red snapper movement.  Home range area was significantly correlated with fish size (407-590 mm standard length), and fish showed the highest site fidelity compared to any previous study (88 % still present after > 10 months).  Red snapper also showed homing behavior, with quick emigrations to other reefs, followed by extended stays at the new reef site, and then a quick return over open habitat to the original release site, with particular individuals repeating this pattern many times.  These consistent long term use patterns of artificial reefs confirm the importance of structured habitat for this species.