Volume 59
The Importance of Sampling across Environmental Gradients in Connectivity Studies
Authors
Rocha, L.A. Download PDF Open PDF in BrowserOther Information
Date: November, 2006
Pages: 629
Event: Proceedings of the Fifty Nine Annual Gulf and Caribbean Fisheries Institute
City: Belize City
Country: Belize
Abstract
The creation of marine protected areas (MPAs) is an important step towards the conservation and management of coral reefs. From a conservation point of view, effective MPAs will serve as source populations for nearby overfished areas, thus, knowledge about larval movement and migration patterns (or connectivity) between areas is of fundamental importance in the design of MPAs. In order to evaluate how well connected the protected and unprotected areas will be, MPA designers usually rely on genetic connectivity studies that compare populations across large geographical scales. However, evidence from recent fish population genetic surveys indicates that geographically close but environmentally distinct locations can be genetically divergent. In the Caribbean, populations of Halichoeres bivittatus in subtropical Florida are very different from those at the tropical Bahamas, and those locations are separated by less than 100 km. In Brazil, reefs at oceanic islands between 200 and 300 km from the coast harbor fish populations that are very different from those along the continental margin. The commonality observed between patterns in the Caribbean and Brazil is that genetic differences correspond to environmental differences. This highlights the importance of sampling across ecologically different reefs in genetic surveys, even those that are geographically close and potentially connected by currents. It also indicates that genetic connectivity studies that cover a combination of geographical and ecological landscapes will provide a better information basis for the selection of sites and sizes of MPAs