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Why is this important?
Local Fisheries
Fishery Management & Biodiversity Conservation
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Why is this important?

Although the total amount of fisheries catches appears to have reached a global maximum over the last decade (Watson and Pauly 2001), many local fisheries are known to be declining worldwide. Whereas industrial scale commercial fisheries often switch to new stocks and species after depleting a resource (sometimes leading to a pattern of serial depletions), people in smaller scale, coastal fisheries are much more vulnerable to fisheries collapses. Coral-reef fisheries, due to their relatively small areas, the slow growth and maturation rates of many reef fishes, and the complex community interactions in reef ecosystems, are especially susceptible to overfishing and habitat degradation (Birkeland 2001). Moreover, overexploitation of key reef species has contributed to the instability and decline of coral reefs, leading to threats to the biological diversity of these rich, biodiverse ecosystems (Hughes et al. 2003, Mumby et al. 2006).

Marine protected areas (MPAs), including marine reserves that restrict all take (or harvest), provide tools for addressing threats from overfishing to both the sustainability of local fisheries and the conservation of biodiversity (NRC 2001). A protected area has been defined as an "area of land and/or sea especially dedicated to the protection and maintenance of biological diversity, and of natural and associated cultural resources, and managed through legal or other effective means" (IUCN, 1994). Protected areas, also known as parks, reserves, and by a suite of other names, have been established at international, regional, national, state, and local scales, and many are linked as networks or other systems. Marine resource managers may opt for different combinations of MPA size, number, location, and other factors, depending on the specific objectives of a marine reserve or other MPA. This may include whether, for example, it is primarily designed for conservation or fisheries, for which target species, and in the context of what kind of fishery (e.g., gear type).

This exercise allows users to explore issues related to marine reserves and local fisheries via interactive simulations. Users are able to control (1) some attributes of a local fishery - including population dynamics and mobility of the target species as well as aspects of fisher behavior and economic factors, and (2) the extent and placement of marine reserves. By exploring the contributions of these issues to fisheries productivity over time, users should gain some understanding of the factors contributing to how reserves can interact with local fisheries. Of course, although many of the factors and dynamics in this exercise are based on actual interdisciplinary research conducted in The Bahamas (see http://bbp.amnh.org), the simulation represents a simplification of the real complexities of population dynamics, fisheries economics, and marine resource management. Adding these additional complexities, such as more variable population dynamics, more dynamic pricing of catches, and additional fishing regulations outside of marine reserves, would likely lead to different quantitative outcomes. Nevertheless, qualitative results deriving from controlled comparisons across different scenarios (e.g., species life-history, fleet, and reserve characteristics) are likely to be more general.

REFERENCES

Birkeland, C. 2001. Can ecosystem management of coral reefs be achieved? Pages 21-25 In B.A. Best and A.H. Bornbusch (eds.) Global trade and consumer choices: coral reefs in crisis. AAAS Publications, Washington, D.C. 39 p.

Hughes, T. P. , A. H. Baird, D. R. Bellwood, M. Card, S. R. Connolly, C. Folke, R. Grosberg, O. Hoegh-Guldberg, J. B. C. Jackson, J. Kleypas, J. M. Lough, P. Marshall, M. Nystr�m, S. R. Palumbi, J. M. Pandolfi, B. Rosen, and J. Roughgarden. 2003. Climate Change, Human Impacts, and the Resilience of Coral Reefs. Science 301: 929-933.

IUCN 1994. Guidelines for Protected Area Management Categories. IUCN, Gland, Switzerland and Cambridge, UK.

National Research Council (NRC). 2001. Marine protected areas: Tools for sustaining ocean ecosystems. Committee on the evaluation, design and monitoring of marine reserves and protected areas in the United States. Ocean Studies Board, National Research Council, Washington, D.C.

Watson R. and D. Pauly. 2001. Systematic distortions in world fisheries catch trends. Nature 414, 534-536.