Marine Protected Areas Possible?
A PFC White Paper
The Pacific Fisheries Coalition (PFC), with support from the PEW Charitable Trusts, the Harold K. L. Castle Foundation, and the Marisla Foundation represents a unique collaboration between conservationists and fishermen who find common ground in their desire to promote the conservation and responsible use of living marine resources in Hawai`i and the Central and Western Pacific.
This white paper was drafted by Linda Paul, Executive Director for Aquatics, Hawaii Audubon Society, with the assistance of the Division of Aquatic Resources.
Fishery Management Methods
Marine Protected Areas: Fishery Management Areas, Marine Life Conservation Districts, & No-Take Reserves
Our most important fishery management objective is to protect the long term health of the stocks to ensure a good harvest for our grandchildren. Many populations of exploited fish are declining in numbers and size despite the best efforts of fishery managers. Sustainable fisheries have become an unreachable goal under current management approaches. Marine protected areas (MPAs) offer a way out of this downward spiral. If some of the larger, more fecund, and genetically more robust fish are fully protected from harvesting, those fish will provide a dependable quantity and quality of offspring. The actual level of protection within different types of MPAs in Hawai`i can vary; most allow some harvesting. The most effective MPAs protect ecosystem structure and function by including a core of no-take reserves in which extraction of all living organisms is prohibited. Because ocean currents transport eggs and larvae over large distances, networks of no-take reserves or Kapu Zones are needed to achieve the stock rebuilding objective. Reserves are also needed to protect functional ecosystems and habitat areas of particular concern and provide baseline data for fisheries managers to measure the health of stocks. Restricting fishing in nursery and spawning grounds to rebuild depleted stocks has long been a part of fisheries management in Hawai`i. Native Hawaiians were the first to use Kapu Zones as a management tool and established caretakers for different areas of land and sea. Hawai`i has several marine protected areas on Oahu, Hawai`i, Lanai and Maui.
Fishery Management Areas (FMAs) are areas that are closed to certain fishing gears or activities, while remaining open to others, or areas that are closed for a length of time and later reopened to allow fish populations to recover and grow to harvestable lengths. Fishing methods may also be restricted to certain types of gear. The Hawai`i bottom fish plan designates 20% of important bottomfish habitat as no-fishing zones for bottomfish around the high islands.
Marine Life Conservation Districts (MLCDs) are marine protected areas that may permit some extractive activities, including certain kinds of recreational fishing such as pole-and-line, spear fishing without SCUBA, and certain types of nets. Commercial fishing is generally forbidden. There are MLCDs at Hanauma Bay, Pupukea, and Waikiki on Oahu; Lapakahi, Kealakekua Bay, Waialea Bay, and the Old Kona Airport on the Island of Hawai`i; Molokini Shoal and Honolua-Mokuleia Bay on Maui; and Manele-Hulopoe on Lanai. Only two, at Hanauma Bay and Waikiki, prohibit all harvesting.
Natural Area Reserves, wildlife sanctuaries and other reserves and refuges are closed to all extractive types of fishing and gathering, except perhaps native Hawaiian harvesting. They include Ahihi-Kinau Natural Area Reserve on Maui, Kaho`olawe Island Reserve, and Coconut Island - Hawai`i Marine Laboratory Refuge on Oahu. Marine Sanctuaries such as the Hawaiian Islands Humpback Whale National Marine Sanctuary usually allow commercial and recreational fishing, although some parts of a sanctuary may be set aside as no-take reserves.
No-Take Marine Reserves
Uncertainty is inherent in managing natural resources, particularly multiple interactions among elements of complex coral reef ecosystems. No-take marine reserves provide insurance against stock collapse and preserve biodiversity. By prohibiting all harvesting within a designated area, complete protection from both the expected and unexpected effects of extractive activities can be achieved. Since fish in no-take reserves aren't caught, or injured and then discarded, they will survive to grow, reproduce and be caught another day. Reserves augment traditional fishery management approaches and make ecosystem management possible. By utilizing a management tool that focuses on ecosystem processes and functions, the fishery and conservation benefits of reserves also extend beyond the individual targeted populations. Ecosystem management is important because high-volume harvesting of selected species can modify predator/prey relationships and result in widespread changes that cascade though out marine communities. Entire assemblages of fishes can be wiped out by using non-specific gear such as gillnets. Many types of gear also destroy spawning and foraging habitats. Besides eliminating the harvesting of targeted species, no-take reserves provide additional benefits by eliminating fishing mortality of associated species due to bycatch, discards and ghost fishing.
Networks of marine reserves offer the best hedge against overfishing within a biogeographic region by connecting egg and larval dispersal and juvenile and adult migration paths. Networks also enhance opportunities to build scientific understanding of complex marine ecosystems by protecting interdependent populations from extractive activities. Furthermore, even though pristine areas and lightly exploited populations such as those in the Northwestern Hawaiian Islands may be the best candidates for protection, even highly degraded areas offer opportunities to restore marine ecosystems. In fact, highly exploited areas such as those adjacent to urban population centers may show stronger responses to reserve designation, but their success with depend on protection from other forms of human disturbance such as pollution and runoff.
The first formal marine reserves in the United States were established more than 20 years ago. After just one or two years of complete protection, researchers found that fish numbers had nearly doubled, their average sizes were up by a third and the diversity of species was higher by one-fourth. The overall biomass in the reserves had almost tripled. However, full protection is critical to achieve the full range of benefits.
Demonstrated benefits of marine reserves and networks of reserves:
Long lasting and often rapid increases in abundance, diversity and productivity of fish populations. Increase in fish size and reproductive output within the reserves. Decreased mortality, decreased habitat destruction, decreased extinction, and balanced, healthy ecosystems. Provide sites for collecting valuable fishery-independent data. Larger reserve sizes result in increased benefits, but even small reserves have positive effects if they are part of a network. Size and abundance of harvested species increase in areas adjacent to reserves (spill-over). Networks of reserves buffer against environmental variability and provide significantly greater protection for marine communities than a single reserve. Reserve networks that span large geographic distances and encompass substantial areas protect against catastrophic events and provide stable platforms for sustainable marine communities in the long term.
"Marine reserves work and they work fast. It is no longer a question of whether to set aside fully protected areas in the ocean, but where to establish them." (Dr. Jan Lubchenco)
"The results are startling and consistent" (Dr. Robert Warner)
A well designed network of fully protected sanctuaries is "a powerful tool for marine conservation and management" (Dr. Steve Palumbi)
The Spill-over Effect
Reserves serve as natural hatcheries, replenishing fish populations regionally through egg and larval spillover beyond reserve boundaries. The dispersal of eggs and larvae from no-take marine reserves to surrounding areas can maintain and improve fishing in adjacent areas because large individuals in the reserve escape capture and their total egg production is much higher. The size and abundance of exploited species also increases in areas adjacent to reserves. Fishermen excluded from marine reserves are the generally the ones that benefit the most, because fishing in neighboring areas is vastly improved.
Examples of the spill-over effect in Hawai`i:
Hanauma Bay. Fish are more abundant beyond and on either side of Hanauma Bay because the overflow of various species enhances the stocks in the adjacent areas. This domino effect has been noticed by fishermen and divers alike.
Kaho`olawe. The Kaho`olawe Island Reserve protects the surrounding waters to a distance of two miles from all activities except tolling twice a month outside of 20 fathoms and some subsistence harvesting. Two years after the reserve was established a survey revealed significantly higher levels of bottomfish inside the reserve than anywhere else in the main islands and an initial pattern of migration into and out of the reserve. There is anecdotal evidence that fishing has improved in the waters adjacent to the reserve.
Other examples of the spill-over effect:
Leigh Marine Reserve, New Zealand. Despite violent opposition to the reserve at the outset, fishermen became its champions. Twenty years after it was established densities of an exploited snapper had reached nearly 40 times higher inside the reserve than outside. Spiny lobster biomass also increased at rates of 5-11% per year of protection and fishermen are now fishing close to the reserve where catches are better due to the spill-over effect.
Soufriere Marine Management Area St. Lucia, Caribbean. Established in 1995 after three years of negotiation and collaboration between the government and the local community this management area encompasses 11 km of the island's best coral reef habitat. Within the area there are four fully protected zones (about 35% of the coral reef habitat) interspersed with fishing areas that are accessible to local artisanal fishermen. By 1998, commercially important fish stocks had tripled inside the fully protected zones and doubled in the adjacent fishing areas and fish diversity increased by 23%. The economy has also benefitted from jobs created by a growing tourism industry associated with the area.
In 2001 the American Association for the Advancement of Science issued the following Scientific Consensus Statement signed by 161 leading marine scientists and experts on marine reserves:
Fisheries management is an inexact science. It can fail because of oversimplified single- species models, insufficient data, environmental variability, inadequate compliance, and political and economic pressures. Conventional management measures are generally not suited to multi-species, multiple gear fisheries. Sound fisheries management must allow a margin of error for effects of changing environmental conditions and uncertainty or inaccuracies in stock assessment and projected sustainable catch levels. Marine reserves are a precautionary management tool that reduce risk by providing a buffer against the predominant practice of "crisis management", whereby managers attempt to guestimate the maximum exploitation level of the resource (MSY) and then implement conservation measures only after a stock is in trouble. Over-exploitation of a stock often takes years to detect. If a fish stock collapses for whatever reason, marine protected areas and no-take reserves can act as reservoirs that will enable a stock to rebuild at a faster rate than would otherwise be possible. It's like having money in a savings account that can be used to cover an overdrawn checking account. It is important, however, that the process for establishing marine reserves be adaptive so that locations, boundaries and rules can be modified to improve performance. Even well designed networks need occasional tuning.
Marine reserves networks need to:
Marine reserves also create economic opportunities that can contribute as much or more to Hawai`i's economy than commercial fishing, such as ecotourism and ocean wilderness tours, scientific research, marine education, recreational snorkeling and diving, underwater photography, and cultural activities. However, it must be noted that even non-extractive uses can alter and damage reserve ecosystems. Since it is usually easier to prevent environmental damage than to repair it later, caution dictates that in the absence of sufficient information on which to base safe and reliable estimates of the effect of an activity, the burden of proof must shift to those proposing activities that may have a negative effect on the ecosystem. Only after the proposed user has demonstrated with a reasonable degree of certainty that the proposed use will not impose an unacceptable cost or loss to the resource, should that activity be specifically permitted.
Murray, S.N., R.F. Ambrose, J.A. Bohnsack. L.W. Botsford, M..H. Carr, G.E. Davis, P.K. Dayton, D. Gotshall, D.R. Gunderson, M.A. Hixon, J. Lubchenco, M.. Mangel, A. MacCall, D. A. McArdle, J.C. Ogden, J. Roughgarden, R.M. Starr, M.J. Tegner, and M.M. Yoklavich. 1999.
No-take Reserve Networks: Sustaining Fishery Populations and Marine Ecosystems. Fisheries. Vol. 24, No. 11, 11-25.
______. 2001. Scientific Consensus Statement on Marine Reserves and Marine Protected Areas. National Center for Ecological Analysis and Synthesis, University of California, 735 State St. Ste. 300, Santa Barbara, CA 931001.
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