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Although the No-Take Zones in this proposal are intended to primarily target entire ecosystems, we acknowledge that there are biological or economic situations in which a certain organism is of particular importance. In such cases, an understanding of the relevant biology and ecology is critically important. For example, key life stages or migration routes of the target species can be protected by careful placement of reserves (Robichaud & Rose 2004). A land-based analogy is the protection of bird nesting sites and reserves for migratory birds, respectively. Zoning within MPAs can solve the problem when of certain species within the same area need requiring different levels of protection. This method has been used in existing MPAs to provide strict restrictions on those populations that are most in danger of long-term extinction. (HOW TO CITE??? http://mpa.gov/helpful_resources/florida_keys.html#doc%202000
) Another form of zoning regards vertical zoning. Vertical zoning allows MPAs to target species that live in a particular depth of the ocean without completely restricting fish in that area. These can be particularly useful when protecting life on the ocean floor from particular destructive methods of fishing such as trawling. (HOW TO CITE?? http://mpa.gov/pdf/helpful-resources/factsheets/vert-zoning-n-bpl0306.pdf)
When setting up marine reserves, it is also important to consider potential ecological barriers that will prevent the occurrence of spillover, and therefore reduce the ability of the protected area to enhance adjacent fisheries. For instance, one study in the Turks and Caicos Islands found that numerous shallow sand habitats enclosed a population of conch, reducing its spillover into nearby areas (A. Tewfik and C. Bene, 2003).
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