The Benefits of No-Take Zones
Figure 1: Taken from the Marine Reserves Work.
Ecological Protection and Recovery:
Over several decades of experience, areas where strict no-take regulations have been in effect have shown some of the most dramatically positive ecological results of any management method. Such benefits can be most clearly seen in areas that have remained relatively pristine thanks to long-standing protection. Significant portions of the Great Barrier Reef off the Australian coast have been protected from human disturbance for over 30 years (Australian Department of Environment and Heritage 2006) with compelling results. Studies in no-take areas of the park show that the biomass of certain fish species has been maintained at levels up to several orders of magnitude higher than in nearby fished areas (Evans & Russ 2004).
Marine reserves have also been shown to facilitate the recovery of severely damaged ecosystems. For instance, large sections of Georges Bank off the coast of Massachusetts were closed to fishing in 1995. Hermen, Collie, and Valentine (2003) began noting "steady and marked increase...in production" within just a few years after the closure. As a matter of fact, the improved survival rate of the 1995 year class of cod on Georges Bank was noted as the primary source of increased biomass for the four year period following the closures (Canadian Department of Fisheries and Oceans 1999). In general, signs of recovery can appear quickly, sometimes within 2-5 years of the establishment of no-take area, and tend to persist for as long as protection remains in effect (Gell & Roberts 2003).
Furthermore, the benefits of no-take zones are inherently ecosystem-based; that is, they are generally seen across a broad taxonomic range of organisms as well as in the improved state of the non-living habitat (Gell & Roberts 2003). These types of positive ecological results of no-take zones have been seen around the globe, and are well documented in the scientific literature and well accepted by the scientific community.
In addition, marine reserves provide significant value for scientific research by being a control against which outside changes can be compared. This can greatly alleviate one of the historic problems of ecological science: the difficulty in interpreting results from the "experimental" areas that have been disturbed by human activities. Long-established marine reserves provide researchers with a baseline healthy ecosystem that cannot be fully duplicated with any other methods or models. Even areas closed due to severe environmental damage can provide important data, such as the natural recovery rates of various species and habitats. In particular, such data allows a quantitative judgment on the effectiveness of marine reserves in facilitating the recovery of fisheries and ecosystems (Hermens, Collie, & Valentine 2003). This type of science that only marine reserves can provide is useful not only for examining and adjusting the MPAs themselves, but also for informing and improving management systems outside of the reserves.
The "Spillover" Effect."
One of the most interesting aspects of Marine Reserves is the so-called "Spillover Effect," by which improved biomass and diversity within the reserves enhances nearby fisheries and ecosystems. Beginning with the work of Roberts, et. al. (1997), the existence of such an effect has been noted and studied for over a decade. In particular, Roberts noted that the dispersal of pelagic larvae from protected areas enhanced the productivity of "downstream" regions and made them more resilient to change. There are numerous documented examples of spillover benefits, from all parts of the world, ranging from the closed area off Cape Canaveral in Florida (Johnson, Funicelli, & Bohnsack 1999) to the examples in the Philippines (Russ, Alcala, & Maypa 2003) and off the coasts of Kenya and Tanzania (McClanahan, Verheij, & Maina 2006).
Although there is only limited evidence of the long-term benefits of spillover, such evidence has been increasing, especially as longer-term data has become available (R.A. Abesamis et. al., 2006). Abesamis, et. al. (2006) proposes that a shallow "decreasing gradient of abundance of targeted fish across a no-take reserve boundary" is evidence for spillover. For instance, if a population increases inside a reserve, some of the fish would tend to move away from the more population-dense areas because of resource competition. However, local environmental characteristics can also influence an abundance gradient, since population is usually higher in areas with more resources and in complex habitats (R.A. Abesamis et. al. 2006). One study on abundance gradients of fish across the boundaries of protected areas near two small Philippine Islands (which used a control section without a reserve) found that three of four reserve boundaries had shallow gradients of decreasing abundance. Although habitat factors could not explain the cases where there was sharp decline in abundance across the boundary, the evidence, in general suggests the existence of spillover in many cases (R. A. Abesamis et. al. 2006).
Another example of clear evidence for biological dispersal from marine protected areas was an experiment in which 90 blue cod were tagged and released at four sites, two of which were in and two of which were next to a closed areas near Long Island, New York (R.G. Cole et. al. 2000). Fewer resightings of tagged fish occurred in the reserve than outside, but the resights in the reserve were larger on average than those outside (R.G. Cole et. al. 2000). The smaller number of resights in marine reserves, despite the absence of fishing in the protected areas, suggests that the blue cod migrate longer distances in reserve sites than in fished areas. Such evidence supports the claim that blue cod will grow to larger sizes in marine reserves and, through spillover, help supply nearby fisheries through spillover (R.G. Cole et. al. 2000).
As part of increasing evidence of spillover in general, it is strongly predicted that protected areas will allow spillover benefits in certain commercially important species. For example, several studies in New Zealand suggest that a small number of spiny lobsters in a given population will migrate large distances (R. J. Davidson et. al. 2002). Based on this evidence, it is likely that marine protected areas can protect a significant percentage of the population of spiny lobsters while providing spillover benefits to surrounding fisheries (R. J. Davidson et. al. 2002). Another study in the Western Mediterranean using catch and effort data about lobster, as well as data from tagged lobsters released in the reserve, suggested that the declining density gradient of lobster is caused by lobsters migrating away from the reserve (Goñi et al. 2006). While it is possible that other factors could have caused the density gradient, the establishment of the protected area there probably caused increased export and spillover (Goñi et al. 2006).
When healthy, oceans can supply many products and services essential to human society, from fish and minerals to transportation and recreation. Healthy oceans possess an enormous capacity for waste conversion. And in recent years, it has been shown that the oceans play a key role in global climate change. All such benefits of the environment to humans are collectively termed ecosystem services (Ecological Society of America 2000).
It has been noted that "properly designed reserves can be effective tools for protecting and restoring ocean ecosystems," because the protection offered by marine reserves allows altered marine environments to return to more natural states (Kearny 2000). In a time where there is increasing evidence that "ocean ecosystems are being altered beyond their range of natural variation by a combination of human activities, including fishing, pollution, and coastal development", marine reserves stand at the forefront of returning the oceans to their most beneficial states (New Zealand Biodiversity 2004).
Specific examples of these benefits can be seen with marine microbes in coral reef systems. According to Blue Frontier: Saving America's Living Seas, such microbes hold great promise for pharmaceuticals and agricultural products, including anti-inflammation chemicals from sea feathers, virus killing proteins from sea grass molds, and cancer cell killing compounds from soft corals (Helvarg 2001). Coral reefs are also natural barriers against storms and floods. When the corals are harmed, these defenses weaken, key species are displaced, and the overall health of the marine ecosystem suffers (IUCN 2007). Marine reserves can prevent such events by protecting the overall balance of the ecosystem. For instance, marine reserves can protect large herbivorous grazers, such as parrotfish, from being overfished. Then, the resulting grazing pressure on seaweeds can prevent them from outcompeting the young corals that are needed to rebuild the reefs (Biology News Net 2007). Such examples demonstrate the effectiveness of marine reserves at protecting many aspects of the ocean ecosystem.
When considering the advantages of a healthy marine ecosystem and how marine reserves facilitate the improvement of this ecosystem, it is also important to remember the disadvantages that stem from inaction. For example, when runoff pollutes estuary waters, the presence of a healthy ecosystem with a strong filter-feeding community (a single adult oyster can filter over 60 gallons of water per day!) can go a long way towards mitigating the negative effects (Ulanowicz and Tuttle 1992). When these benthic filter feeders are absent due to overfishing or dredging, the resulting algal blooms can contaminate the water to the point where people at beaches are at risk "for a host of health problems, including gastroenteritis, respiratory infections — illnesses common in the Third World countries — as well as pink eye, ear infections and skin rashes" (Duswn 2007). These waters also poison the marine flora and fauna upon which the fishing industry relies so heavily. It is clear that the health of the oceans correlates strongly to the health of the people. As such, marine reserves are a necessity for the protection and restoration of marine ecosystems, which in turn will help preserve human health and well-being.
Despite common assertions to the contrary, marine reserves can have significant economic benefits to society, including the assurance of long-term, sustainable fisheries. Admittedly, one of the unfortunate short-term effects of marine reserves is the displacement of fishermen due to the reduction of fishable waters, higher levels of congestion, and potential competition. However, in the long term, the establishment of a network of protected areas will inevitably create "optimal harvesting area[s]" with "higher resource rents" (Grafton, Komas, & Pham 2006) under controlled fishing rates. Our particular proposal is designed to mitigate the short term costs, while attempting to ensure that enough of the ocean is protected so that the future potential can be realized.
But perhaps even more exciting are the beneficial economic effects of marine reserves through tourism and other non-exploitative activities. According to the National Marine Protected Areas Center (1995-1996), the Florida Keys National Marine Sanctuary and other marine-related parks and refuges provide an "estimated total tourist contribution to the economy of over 60 percent." Considering the scale of tourism in areas such as the Florida Keys, this is a truly significant percentage. Myriad activities such as scuba diving, wildlife watching, boating, surfing, and snorkeling are part of this large, lucrative, and growing industry.
Another example of the economic benefits of marine reserves can be found in the Isles de Medes in Spain. The general beautification of the area and the simple presence of the reserve generated many tourism, research, and educational opportunities. A study undertaken by TERRA (2003) regarding the economic benefits to the area showed significant results. Over 30,000 beds were added to the hotel capacity of the area, while over 1200 new places of employment were created. Fiscally, additional revenue of 3 million Euros per year was earned by the local economy from tourism and recreational activities. Most importantly, an additional 2.5 million Euros of revenue was generated via visitors to the marine park itself.
Oftentimes, revenues derived from non-extractive uses compare favorably with other more damaging uses of the ocean. For example, consider that whale watching globally generates more than 1 billion USD in revenue per year (Greenpeace 2007a). For Iceland in particular, whale-watching generated around 8.5 million USD per year in revenue, as compared to an average of 3.5-4 million USD from whaling in the years before the onset of the IWC moratorium (Greenpeace 2003). In acknowledgement of such economic realities, the government of Iceland announced in 2007 that it would no longer be issuing commercial whale-hunting quotas (Greenpeace 2007b)
Research and Education
Marine protected aareas can be a fantastic resource for ocean education. Bringing awareness of ocean and environmental issues through tourism and visitation is an effective form of mass education. For a public that is generally aware of the wonder of the marine ecosystem, an experience with snorkeling or glass-bottomed boats could be truly amazing. If even a few can be truly inspired by an experience with a relatively pristine ecosystem, then the endeavor will have been a success. Such experiences can be formalized and reinforced by knowledgeable park staff, informational displays, and other techniques common to national parks and other environmental areas worldwide.
Of course, the educational benefits of marine reserves should not be limited to those with physical access to the reserves. Modern technology, such as webcams and internet connections can bring substantial contact with marine reserves to people and classrooms worldwide. Integrated undersea data and sensor networks, similar to the pioneering Monterey Accelerated Research System, can provide continuous, detailed scientific information about the marine reserves to all who seek it (MBARI 2007). Scientific information and corresponding visuals can be effectively integrated into all levels of formal education, from grade school to professional research. Simple exposure to ocean literacy in school will create a more environmentally aware populace. In addition, the fact that kids often bring what they learned from school home with them will further broaden the potential reach of marine reserves (Nugent 2004).
Furthermore, MPAs are capable of enhancing marine research as with the Ecological Characterization Project undertaken by the National Marine Protected Areas Center (2006). The creation of a scientific journal dedicated to the dissemination of research undertaken in MPAs and marine reserves would also be a useful tool for research and education. Additionally the profits of such a journal (from membership fees and subscriptions) could be distributed back to the MPA from which the data were collected.
MPAs are capable of great feats of research and education when used appropriately. With increased exposure to ocean information, mediated by MPAs, public knowledge of the world ocean problem can become commonplace.