Designing Cost-Effective Artificial Reefs: Fine-Scale Movement and Habitat Use of Red Snapper around a Nearshore Artificial Reef Complex

Artificial reefs are commonly used to provide structured habitat in areas with limited natural habitat to enhance the environment. Creating artificial reefs is expensive, and materials are often limited; thus, discussions are needed regarding the best material and design to maximize reefing efficiency while best meeting the goal of reefing programs. We tracked Red Snapper Lutjanus campechanus, an economically important and reef-dependent species, by using a Vemco Positioning System to determine fine-scale movements and habitat use around a nearshore reef comprised of three types of reefing structure: concrete reef pyramids, concrete culverts, and a sunken ship. Habitat use (core volume and home range, or the probability of a fish being absent 50% or 5% of the time, respectively) was significantly different by month, with the largest movements during summer months. Mean depth values also differed by study month (February-August), with Red Snapper residing deepest in the water column during August and shallowest during April. In the summer months, differences among structure types were observed in core volume use but not home range, suggesting that Red Snapper used similar-sized areas on all three structure types. A high reported recapture rate (77%; 10 of 13 fish) indicated that these easily accessible nearshore reefs undergo heavy fishing pressure. Half of the recaptures were reported as recaptured on a structure other than their tagging structure; however, tagged fish spent the greatest percentage of time on their tagging structure. Red Snapper habitat use was influenced more by the presence of structure than by the type of reefing structure. Using the results from this study combined with a cost comparison of reef types, we argue that use of the least expensive reefing material that covers the largest area may be the best policy in designing future artificial reefs.