Designing marine reserve networks for both conservation and fisheries management

Abstract

Marine protected areas (MPAs) that exclude fishing have been shown repeatedly to enhance the abundance, size, and diversity of species. These benefits, however, mean little to most marine species, because individual protected areas typically are small. To meet the larger-scale conservation challenges facing ocean ecosystems, several nations are expanding the benefits of individual protected areas by building networks of protected areas. Doing so successfully requires a detailed understanding of the ecological and physical characteristics of ocean ecosystems and the responses of humans to spatial closures. There has been enormous scientific interest in these topics, and frameworks for the design of MPA networks for meeting conservation and fishery management goals are emerging. Persistent in the literature is the perception of an inherent tradeoff between achieving conservation and fishery goals. Through a synthetic analysis across these conservation and bioeconomic studies, we construct guidelines for MPA network design that reduce or eliminate this tradeoff. We present size, spacing, location, and configuration guidelines for designing networks that simultaneously can enhance biological conservation and reduce fishery costs or even increase fishery yields and profits. Indeed, in some settings, a well-designed MPA network is critical to the optimal harvest strategy. When reserves benefit fisheries, the optimal area in reserves is moderately large (mode ≈30%). Assessing network design principals is limited currently by the absence of empirical data from large-scale networks. Emerging networks will soon rectify this constraint.biodiversity | fishery profit | ocean policy | sustainability

From the Levant to Gibraltar: A Regional Perspective for Marine Conservation in the Mediterranean Sea

“…Literature on MPA design and management highlights the importance of: (1) connectivity when reserves are small and representation among eco-regions (Adulla et al 2008;Guarderas et al 2008;Gaines et al 2010); (2) suitable management regimes (e.g., Friedlander et al 2003;Vella et al 2009;Olsen et al 2011); and (3) MPA distribution vis-á-vis areas of cumulative impacts (e.g., Planes et al 2000;Coll et al 2011). The first issue assumes principles of biological conservation, especially for the marine environment (Gaines et al 2010).…”

“…The first issue assumes principles of biological conservation, especially for the marine environment (Gaines et al 2010). The second relates to viable mechanisms of governance within and among MPAs.…”

“…1 Variability in definitions impedes assessment of large-scale networks as each country, or region, focuses on varied landscape types and a variety of goals and purposes for their MPAs (Gaines et al 2010).…”

“…National MPAs are those only established and/or recognized in the particular country through local, provincial, or national-level legislation and management regulation. Unlike other studies, the MPAs we consider are not particularly focused on fisheries management (e.g., Gaines et al 2010) but have been designated for a variety of reasons including preserving natural and cultural heritage, education, and research in ''pristine'' settings.…”

“…For marine sites this engenders unique management opportunities and challenges. For example, depth can be very significant in a MPA (Agardy 2000); it is difficult or impossible to put up ''fences'' around MPAs (Dudley 2008); and exploitation of resources adjacent to a reserve for commercial fishing must frequently be reconciled with conservation goals (Gaines et al 2010).…”