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Marine Reserve Management Introduction Conventional species-specific fishery management tools designed to keep catch at the maximum sustainable yield have not prevented overfishing, bycatch, or habitat degradation. Recent amendments to the Magnuson-Stevens Fishery Conservation and Management Act recognize this and direct the National Marine Fisheries Service and the regional fishery management councils to develop fishery management plans that address these problems. Specifically, fishery managers must end overfishing and rebuild overfished stocks, minimize bycatch to the extent practicable, and identify and protect essential fish habitat. Marine reserves are increasingly being proposed as a tool fishery managers might use to meet these challenging directives. But many remain skeptical about the supposed benefits of reserves. Recent calls for widespread implementation of reserve systems in U.S. waters have elevated this debate to the national level. What is a Marine Reserve? The term "marine reserve" can mean different things to different people. As used here, it describes a defined area in marine waters where fishing is prohibited to achieve specific fishery conservation and management objectives. Also commonly referred to as "marine harvest refugia" or "no-take zones," marine reserves provide fish populations a refuge from fishing pressure -- a fundamentally different type of protection than that offered by conventional fishery management tools, such as total allowable catch quotas; size, bag, or trip limits; and gear restrictions. Although fishery managers have historically relied on seasonal and/or temporary area closures to protect fish when they are most vulnerable (i.e., during spawning), marine reserves offer full-time protection on a much longer timescale. What are the Benefits of Marine Reserves? Marine reserves are believed to be a particularly useful tool for managing multispecies fisheries and fisheries that target species with behavioral or life history characteristics that make them vulnerable to overfishing. Advocates of marine reserves commonly cite five main benefits to fisheries:
Marine reserves improve natural population structures within their borders. Fish populations protected from fishing pressure can become structured by natural mortality rather than fishing mortality. They are also protected from common problems associated with fishing, such as the selective removal of large breeder fish, incidental catch and mortality, and habitat degradation, each of which can alter ecosystem structure and function. Preserving the natural structure of fish populations within the reserve area can, ultimately, enhance the resiliency of these populations to outside pressures. Marine reserves increase the individual size and abundance of fish both inside and outside their borders. There is evidence from around the world that marine reserves support fish populations of increased abundance, density, size, and age classes within their borders. These benefits allow protected populations to increase their reproductive output and potentially replenish fisheries outside their borders through dispersal of eggs and larvae. Marine reserves may also replenish nearby fisheries through direct migration of adult fish. Because fish protected within a marine reserve are generally larger, direct migration can provide added benefits to recreational fishermen in the form of "trophy" fish and to commercial fishermen in terms of increased profits. Marine reserves provide insurance against scientific uncertainty. One of the greatest challenges in fishery management is the uncertainty associated with setting safe and appropriate catch levels for individual fish stocks and trying to predict variations in natural conditions. Marine reserves can protect a portion of fish populations from potentially irreversible damage resulting from erroneous fishery management decisions. Marine reserves provide scientific research opportunities. Marine reserves can improve the scientific basis for fishery management decisionmaking by offering scientists ecological benchmarks against which fishing impacts can be measured, as well as baseline data on the age, growth, life history parameters and ecological interactions of marine communities. What are the Drawbacks of Marine Reserves? Opponents of marine reserves commonly cite four major drawbacks:
Marine reserves displace fishermen. Closing fishing grounds will displace some fishermen. Whether they travel to new grounds or enter new fisheries, this displacement could result in economic losses (at least over the short term) if they must travel farther to fish or if the new location and/or fishery is unfamiliar to them, less productive, or the catch less valuable. In addition, displacement is likely to increase competition and allocation battles in fishing grounds outside reserve areas and contribute to overcapacity problems in fisheries that are not protected under a limited access system. Marine reserves offer incomplete protection. Marine reserves cannot protect fish from the effects of natural environmental variability or other activities that are out of the hands of fishery managers. Adverse impacts resulting from both natural (i.e., storm and El Niņo Southern Oscillation events, climate variability, disease epidemics) and human (i.e., point source and non-point source pollution, physical alteration of the shoreline) pressures could reduce or eliminate the anticipated benefits of a marine reserve. In this way, even perfectly sited reserves involve a certain degree of risk. Marine reserves may be expensive to enforce. Increases in species abundance, diversity and size inside reserve boundaries are likely to create a strong incentive for poaching, and poaching has been reported as a problem in some fisheries where marine reserves have been applied. Rigorous enforcement may require the use of costly electronic vessel monitoring devices, particularly for offshore areas that are more difficult to reach. Where Has Marine Reserve Management Been Applied? Many marine habitats around the world are afforded some form of protection for conservation, recreation and/or other reasons. However, relatively few of these protections take the form of strict prohibitions on fishing to achieve fishery conservation and management objectives. This is particularly true in the United States. The United States manages a fragmented network of marine protected areas at the federal and state levels, through the National Oceanic and Atmospheric Administration's (NOAA) National Ocean Service, the U.S. National Park Service, and state and territorial marine resource agencies. These protected areas differ in management goals, as well as the type and degree of protection they afford. Prohibitions on fishing within these areas have not generally been prescribed or well received where applied. Marine reserves are few in number and small in scale. Currently they cover less than one-tenth of one percent of U.S. marine waters-well below the two percent minimum benchmark goal (including twenty percent coverage of each ecosystem type) that has been recommended in recent calls for presidential action. But this trend appears to be changing. The Florida Keys National Marine Sanctuary, the National Park Service, the Florida Fish and Wildlife Commission, and the Gulf of Mexico Fishery Management Council are currently negotiating the establishment of a 186-nautical square mile marine reserve in the Dry Tortugas. Each of these agencies has some authority in the area, and each was involved in designing the reserve, along with scientists, commercial and recreational fishermen, divers and environmental representatives. When implemented, the Tortugas Ecological Reserve will be the second largest marine reserve in the world. Several other reserve systems are also under consideration. NOAA's National Ocean Service is considering designating reserve areas inside three other national marine sanctuaries. Several regional fishery management councils have formed multi-sector marine reserve advisory committees to examine the usefulness of reserve management in their fisheries. And some U.S. states and territories are considering creating reserves, or modifying existing reserves, within waters under their jurisdiction. Conclusion Marine reserves offer fishery managers a unique alternative to conventional fishery management tools and a real opportunity to resolve decades of problems that have resulted in increasingly restrictive fishery management measures. But, like all other fishery management tools, marine reserves also have drawbacks and they are likely to be more effective in, and applicable to, some fisheries than others. Current considerations are likely to lead to additional marine reserve designations in the future. The collective participation of all fishery interests in these discussions can help to ensure that the design and objectives of new designations are developed in a way that make them successful and effective. Sources and Recommended Reading
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