Ricardo Garla – Departamento de Botânica, Ecologia e Zoologia, Universidade Federal do Rio Grande do Norte
Demain Chapman & Mahmood Shivji – Guy Harvey Research Institute, Nova Southeastern University
Brad Wetherbee – Department of Biological Sciences, University of Rhode Island

The Caribbean reef shark, Carcharhinus perezi is an important, but poorly understood apex predator important in shaping the ecology of coral reef ecosystems throughout the Caribbean, Gulf of Mexico and east coast of South America.  The goals of this project were to characterize the nursery areas used by Caribbean reef sharks at a location where they are common and where the presence of marine protected areas (MPAs) may help to sustain their local populations.  Standardized fishing surveys were conducted from 1999 to 2003 to describe the spatial distribution, nursery habitat and the time of parturition of Caribbean reef sharks at Fernando de Noronha.  The capture of 143 individuals (71-224 cm) indicated that the insular shelf (from 5-30 m depth) is used as nursery area by this species and that parturition occurs from December to April, with a peak in February-March. These sharks were uncommon outside the marine protected area. Additionally, we examined themovement patterns and long term site-fidelity of Caribbean reef sharks using tag-recapture and automated telemetry at Fernando de Noronha.  Twenty-two of 143 (15.3%) externally tagged juvenile sharks (<110cm) were recaptured between 0-5 km from the site of tagging after 5-800 days at liberty, suggesting some site fidelity in young individuals of this species. Site-fidelity and movement patterns of ten juvenile sharks ranging from 78 to 110 cm, and one adult female (224 cm), were also investigated for periods of up to two years with an array of automated telemetry receivers. Catch-per-unit effort and telemetry data from inside and outside a marine protected area (MPA) both show that shark abundance and activity is greatest along the part of the archipelago’s coastline least disturbed by human activity.Juvenile sharks demonstrated a high degree of site-fidelity and occupied specific locations along the coast throughout the year, with some evidence of increased activity space with ontogeny. Sharks appeared to range more widely at night and there were no seasonal variations in habitat use. Our results suggest that marine protected areas may be a useful conservation tool to protect young Caribbean reef sharks and potentially other reef-dwelling carcharhinid sharks during their early life-history.

For pdf versions of publications resulting from our study click on the manuscript below.

Garla, R.C., D.D. Chapman, M. Shivji, B.M. Wetherbee & A.F. Amorim. 2006. Habitat of juvenile Caribbean reef sharks, Carcharhinus perezi, at two oceanic insular marine protected areas in the southwestern Atlantic Ocean : Fernando de Noronha Archipelago and Atol das Rocas, Brazil . Fish Res. 81:236-241.

Garla, R.C., D.D. Chapman, B.M. Wetherbee, M., Shivji. 2006. Movement patterns of young Caribbean reef sharks, Carcharhinus perezi, at Fernando de Noronha Archipelago, Brazil : the potential of marine protected areas for conservation of a nursery ground. Mar. Bio. 149(2):189-199.