Selecting Sites for MPAs: How Practitioners Have Used Different Methods in Planning MPA Networks

MPA News

In designing MPA networks, planners must decide how they will choose which sites to include. There are a variety of ways to select sites, from simple ones (having experts make a list based on their best judgment) to complex (using advanced software to consider an array of ecological and socioeconomic factors). There are also questions on how best to classify the area you seek to protect. After all, if you aim to have a representative network of MPAs, you need to know what characteristics or habitats you want represented within it, and how to include samples of each in the network.

This month, MPA News briefly examines methods that practitioners have used in planning representative MPA networks, and offers cases in which planners explain how they chose their methods.

Site-selection methods

Among the most basic ways of selecting sites is to convene a panel of experts to do it. Often called the Delphic method, it normally involves experts answering a questionnaire - in this case, on which sites to include in an MPA network - then discussing the answers. The goal is consensus. In 2002, for example, a panel of 62 scientists and conservationists met in Vietnam to develop a global list of "areas of outstanding universal value for marine biodiversity" for potential future inclusion in the UNESCO World Heritage program. The panel identified 79 areas of importance that merited World Heritage status, based on the knowledge and expertise of the panelists. A report on the meeting ("The Hanoi Statement") including the list of sites is at http://whc.unesco.org/en/events/501.

Another method of selecting sites involves using relatively simple scoring systems. These systems assign a rank of relative importance to candidate sites based on various user-defined criteria. An example of this was the ranking system devised for the Bahamas in 1999-2000 when that country anticipated designating a network of MPAs. The system ranked candidate sites on a scale of 1 to 3 for each of several socioeconomic criteria (fishing impact, community management, community benefits) and ecological criteria (habitat diversity, regional importance). The system was described in our February 2000 edition (MPA News 1:5), and is revisited below.

The most complex method of site selection - but also the one that promises an "optimal" network design - involves using software tools to process large amounts of information. The software Marxan, for example, allows practitioners to account for multiple species, habitats, oceanographic factors, resource uses, and other considerations across a wide geographic area. It has been used in multiple MPA-planning processes in recent years, including for Australia's Great Barrier Reef Marine Park and in British Columbia, Canada ("Using Computer Software to Design Marine Reserve Networks", MPA News 6:4).

Each system has its advantages and disadvantages. A major advantage to the Delphic method, for example, is its ease. It relies simply on the knowledge of the participants, and requires no significant scoring system or computing expertise. However, its clear basis on human judgment can be limiting. Although no site-selection system is free from human biases, the biases are particularly apparent in the Delphic method, where "experts" wield the decision-making power and stakeholders may potentially feel alienated from the process (unless stakeholders are included as experts). In contrast, Marxan-based planning processes have been opened to the public in some cases, where stakeholders have been able to suggest potential MPA sites and see on a computer screen how well they would fit in a network. This was done in the process to plan no-take reserves within the Channel Islands National Marine Sanctuary in the US ("Science as a Central Tool in Planning Marine Reserves", MPA News 2:10).

In practice, these methods are often not exclusive. A scoring system, for example, may be applied to candidate sites that were originally selected by a Delphic panel of experts. And nearly all selection systems are influenced by political considerations before the final designation of sites.

[For a more detailed comparison of various site selection methods, see Evaluation of Site Selection Methodologies for Use in Marine Protected Area Network Design, a 2004 report prepared for the Canadian Science Advisory Secretariat. It is available at www.dfo-mpo.gc.ca/csas/Csas/DocREC/2004/RES2004_082_e.pdf.]

Bahamas: Revisiting the site-ranking system for a national MPA network

In 1999, the government of the Bahamas sought to designate a network of no-take marine reserves in its waters, and asked US scientists Craig Dahlgren, Mark Hixon, and Allan Stoner to devise a system for selecting the sites. There was time pressure: the team was given just a few weeks to create the ranking system and recommend areas. The team first listed 30 candidate sites, then applied the ranking system and recommended the five highest-scoring sites. Since then, the five sites have undergone extensive stakeholder consultation and been modified; the designation process is ongoing. (Delays in designation have been partly due to changes in the Bahamian government between then and now.)

The Bahamas site-ranking system remains a model of conciseness in MPA planning, especially as compared to more recent Marxan-based methods. The impact of various sites on fishing activity, for example, was scored as 1 point for major displacement, 2 points for minor displacement, and 3 points for negligible displacement. Similarly, sites scored highly if they had a supportive community nearby, if they contained both reef and seagrass habitats (as opposed to one or the other), and if they were thought to serve as a major source of fish larvae to the rest of the Bahamas.

Dahlgren, who is now at the Perry Institute of Marine Science in the US, says the emphasis in creating the system was on speed and simplicity. "The system was simple out of necessity," he says. "To take advantage of a narrow political time window, our ranking criteria were created very quickly and with minimal information. There were not many site-specific data available to us, we had no time to collect new data, and more advanced tools were not available. Marxan, for example, was just being developed at the time."

Dahlgren says the main benefit of the ranking system was that it allowed his team to provide policy-makers with the information they needed to move forward with MPA planning rapidly and at minimal cost. "While the level of detail and accuracy that our system provided may make many scientists cringe, the simplicity of the system and amount of information provided was actually well-suited to the political decision-making process at the time," he says. "The tradeoff was that our simple system, and how it was used, provided only very basic information to decision-makers.

"If we were to evaluate the same sites today, we would probably be able to improve upon our earlier system," says Dahlgren, noting an increase in available information about general ecological processes, the distribution of key species, and socioeconomic factors in the Bahamas, as well as improved data on site-specific conditions. "We would be able to evaluate various criteria in greater detail and make more accurate assessments of conditions. Having said that, I am not sure an improved ranking system would change site rankings considerably."

Dan Brumbaugh directs the Bahamas Biocomplexity Project (BBP), an interdisciplinary initiative to improve the design of MPA networks for biodiversity conservation, fisheries sustainability, and other uses (http://bbp.amnh.org/website/home.html). He cites the effort by Dahlgren (who is also a BBP collaborator), Stoner, and Hixon as an important forerunner to BBP's work in that it included both ecological and social criteria in its rankings. "Given their limited resources and timeframe, it was probably the best approach available, although time and further study have understandably revealed various shortcomings in the analysis," says Brumbaugh. "Proposed reserve areas that were initially judged to be socially acceptable turned out to be more controversial once a wider set of stakeholders became aware and involved in the actual planning discussions. This underscores some of the risks inherent in both misidentifying affected communities as well as over-generalizing about community-level responses (vs. subsets of stakeholder interests) to MPA proposals. To the extent that we should always try to use the best available science for policy considerations, after years of multidisciplinary investigation, we simply have far more to consider now than what they had at their disposal."

If a site-selection process for the Bahamas were to be conducted today, Brumbaugh describes how he would do it. "Given the growing number of site-selection tools, including new data layers and algorithms, we have the means to more explicitly define many more types of objectives for a system of MPAs in the Bahamas," he says. "My approach therefore - given the luxuries of hindsight, new information and tools, and enough time and money to implement them appropriately - would be to avoid an expert-driven analysis. Rather, an integrated natural-social science research team would assist the Department of Marine Resources, the Bahamas National Trust, and other relevant agencies in their work with as many local settlements as possible. Consensus would be sought on what set of features are most valued; what important datasets are still missing but feasible; how much of each feature Bahamians want to conserve; and, ultimately, what Bahamian MPA networks incorporating as many of these objectives as possible could look like. Deepening the interaction with and among stakeholders to make new scientific tools accessible for planning is an excellent way to facilitate as much science-based planning as possible. It also helps to generate the kind of community buy-in that new MPAs ultimately need to be effective."

Site selection in Australia: Great Barrier Reef Marine Park and South Australia

Selecting sites for a representative system of MPAs requires a way to classify the biogeography of the area, such as into "ecoregions", "bioregions", habitats, or other classifications. Graeme Kelleher wrote in Guidelines for Marine Protected Areas (IUCN, 1999, www.iucn.org/dbtw-wpd/edocs/PAG-003.pdf):

"The biogeographic classification system used by a country in developing such a representative system need not be universally applicable. Indeed, if the world were to wait for general scientific agreement on the 'best' such classification system, it would probably be a long time before a start was made in establishing many MPAs. The important thing is that the biogeographic system used in a particular country suits that country's existing scientific and information base."

In Australia alone, different classification systems have been used for different MPA-planning initiatives. The Representative Areas Program (RAP) of the Great Barrier Reef Marine Park, in which no-take zones in the park were expanded, involved subdividing the park into 70 bioregions, then setting aside at least 20% of each bioregion in no-take zones (MPA News 5:10). In contrast, the state of South Australia, which has roughly the same length of coastline as the Great Barrier Reef Marine Park, subdivides its marine waters into just eight bioregions, and is engaged in designing MPAs within those bioregions.

Deciding what constitutes a "bioregion" is obviously open to interpretation, and dependent on the level of available information. It also affects the ultimate design of a representative MPA network if you are taking a bioregional approach.

Leanne Fernandes, who managed RAP and now runs Earth to Ocean Consulting, says the term "bioregion" as used by RAP was not technically correct but represented a compromise between a biologically appropriate description and a socially meaningful one. "Bioregions, as used in biogeography, are at a far larger scale than those defined for the Great Barrier Reef (GBR) ecosystem," says Fernandes. "Some global bioregionalizations have the entire GBR ecosystem as one 'bioregion', for example; likewise the Interim Marine and Coastal Regionalisation of Australia (IMCRA) had the GBR encompassed within nine regions (www.environment.gov.au/coasts/mbp/imcra/index.html). For the RAP's planning and management purposes, this was too broad a scale. Given the available knowledge on the GBR, our experts were able to define 70 bioregions for the GBR ecosystem, including 30 reef bioregions and 40 non-reef bioregions." She notes that datasets for the IMCRA process were each required to cover the entirety of Australia's waters, which limited the number of usable datasets. In contrast, because GBR in particular is so heavily studied, far more datasets were available to RAP than the IMCRA process could use.

"The term 'bioregion' is an abbreviation of 'biological region', which was something we could talk to the community about," says Fernandes. "People understood that 'bio' referred in some way to plants and animals. To many people, the term 'bioregion' made sense to describe a region within which plants and animals were more similar to each other than they were to plants and animals in another region."

If the scale of classification had been broader, says Fernandes, the zoning outcome might have been different. Namely, it might have missed protecting ecosystem elements about which little is currently known. "There was not perfect information for all the habitats and species that comprise the GBR ecosystem," she says. "By defining bioregions at the scale we used, we ensured a comprehensive description of the biodiversity of the entire system. The likelihood of failing to protect some part of the ecosystem about which little is known would have been greater if a broader-scale bioregionalization had been applied in the RAP."

To help guide its site selection, the RAP established a list of 11 biophysical operating principles, including that whole reefs must be included in no-take zones, and that most no-take zones be at least 20 km along their smallest dimension. Fernandes says the latter principle was a challenge to follow. "Complying with the minimum-size principle was the most difficult one, as we were also trying to comply with socioeconomic, cultural and management feasibility principles - one of which was to aim to minimize conflict with human uses," she says. She notes that prior to the rezoning, just one no-take zone in the park measured 20 km or more across its smallest dimension. The RAP website is at www.gbrmpa.gov.au/corp_site/management/representative_areas_program.

South Australia has also established design principles to guide its MPA-planning process. Released in June 2008, the 14 principles include ones to ensure the system is representative ("The system must reflect the variety of our marine life") and does not discriminate against certain groups ("Give consideration to the full diversity of marine users" and "Respect indigenous interests and culture"). South Australian Minister for the Environment Jay Weatherill said, "The design principles reflect the latest thinking and international best practice in designing and selecting marine parks." A document describing the design principles is available at www.environment.sa.gov.au/coasts/marineparks.html.

Prior to setting the principles, however, South Australia decided roughly where its marine parks would be sited - what planners have called "focus locations". There are 19 focus locations, representing island groups, gulfs, peninsulas, and other noteworthy features (www.environment.sa.gov.au/coasts/marineparks/locations.html). One marine park will eventually be sited in each focus location, and boundaries for those MPAs will be set in the coming months. "Decisions on the boundaries of the marine parks in each of the focus locations will be guided by the design principles," says Bryan McDonald of South Australia's Department for Environment & Heritage.

Although the South Australia process is underpinned by bioregional considerations, the 19 focus locations are not evenly distributed across all bioregions. One relatively homogeneous bioregion contains just a single focus location, whereas another, more-complex bioregion contains ten. The South Australian government says the 19 focus locations will ensure a representative network of MPAs "that will collectively conserve and protect all known types of habitats and communities within South Australia."

For more information:

Craig Dahlgren, Perry Institute for Marine Science, Jupiter, Florida, US. E-mail: cdahlgren [at] perryinstitute.org

Dan Brumbaugh, American Museum of Natural History, New York City, US. E-mail: dbrumbaugh [at] amnh.org

Leanne Fernandes, Earth to Ocean Consulting, Queensland, Australia. E-mail: leannef [at] earth2ocean.com

Angela Gray, Department for Environment & Heritage, South Australia, Australia. E-mail: Gray.Angela [at] saugov.sa.gov.au