Diversity and Movement of Reef-Associated Elasmobranchs at a Caribbean Oceanic Atoll (Glover's Reef, Belize): Implications for Marine Reserve Design

Little is known about the sharks and rays of the Mesoamerican Caribbean. Studies of the elasmobranch fauna of Glover’s Reef Marine Reserve (GRMR), Belize, demonstrate its importance for a diversity of elasmobranchs and provide essential information for marine protected area design. A five year survey documents GRMR as a nursery area for four species of elasmobranchs and the use of the atoll by eight other species (6 sharks, 2 batoids), including the Galapagos shark, C. galapagensis, previously known in the Caribbean from only one specimen. Differences exist in elasmobranch abundance, species composition and intraspecific size distribution among shallow lagoon, deep lagoon, ocean reef, and inshore habitats. Telemetry studies of two common sharks illustrate movement within and outside of the atoll and across the boundaries of the no-take zone of the marine reserve. GRMR is an important breeding ground for several species of elasmobranchs and in need of further study and conservation. For effective conservation of elasmobranchs, an ecosystem based approach should be taken in designing marine protected areas. Zoned management plans are needed that incorporate a fairly large no-take reserve that protects diverse habitats and the connections between them, surrounded by a larger area where fishing is regulated.