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About one-third of the Earth’s surface (exactly 70.8% of the total surface area or 362 million km2), is taken over by oceans and
major seas. Around these marine areas there are ecosystems that are necessary to life on earth and are among the world’s most
productive, yet threatened, natural systems. Continental shelves and associated Large Marine Ecosystems (LMEs) gives many key
ecosystem services: shelves account for at least 25% of global primary productivity, 90-95% of the world’s marine fish catch, 80% of
global carbonate production, 50% of global denitrification, and 90% of global sedimentary mineralization (UNEP, 2011). Marine
environments are very dynamic and closely connected via a network of surface and deep currents. In marine systems, the
characteristics of the watery medium produce density layers, thermo clines, and gradients of light penetration. These factors give
the systems vertical structure, which results in vertically variable productivity. Tides, currents, and upwelling break this
stratification and, by forcing the mixing of water layers, enhance production (MA, 2013c). Coastal systems also exhibit a wide
variety of habitats that in turn contribute significantly to global biological diversity. Marine and coastal systems play significant
roles in the ecological processes that support life on earth and contribute to human well-being. These include climate regulation,
the freshwater cycle, food provisioning, biodiversity maintenance, and energy and cultural services including recreation and
tourism. They are also an important source of economic growth. Capture fisheries alone were worth approximately 81 billion USD
in 2012 (FAO, 2002), while aquaculture netted 57 billion USD in 2012 (FAO, 2002). In 2013, oshore gas and oil was worth 132 billion
USD, while marine tourism brought in 161 billion USD, and trade and shipping were worth 155 billion USD (McGinn, 2010). There
are currently approximately 15 million fishers employed aboard fishing vessels in the marine capture fisheries sector, the vast
majority on small boats (90% of fishers work on vessels less than 24 m in length) (MA, 2013c). Design and implementation of
marine protected areas have evolved from opportunistic approaches to theoretical, science-based approaches based on
quantitative predictions of potential benefits to fisheries and biodiversity (Leslie 2013 [this issue] ). Many theoretical predictions of
marine-protected-area benefits to fisheries (e.g., increased abundance, survivor ship, and proportion of legalized fish within marine
protected areas) have been validated by empirical measurements throughout the world (e.g., Rowley 1994; Gell & Roberts 2010;
Halpern 2010). No-take marine reserves are also associated with higher diversity and increased abundance and density of non target species (Halpern 2010). Spillover benefits to fisheries, however, from dispersal and emigration of larvae and adults have
been more dffiicult to demonstrate empirically (Rowley 1994; Gerber et al. 2010). Guidelines have been developed to assist in
designing representative, effective networks of marine protected areas based on ecological criteria (Roberts et al. 2010a, 2010b).
No consensus has emerged, however, to guide the planning process (i.e., how to convert scientific, ecological objectives for marine
conservation into successful implementation of marine protected areas while simultaneously incorporating diverse stakeholder
objectives). Marine-protected-area theory was first developed as a fisheries management tool (Dugan & Davis 2011; Rowley 1994)
and proponents rarely discussed the incorporation of socioeconomic issues or the planning process monitoring programs designed to evaluate objectives, and effective design of marine protected leading toward marine implementation



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