Systematic marine conservation planning in data-poor regions: Socioeconomic data is essential

Abstract

Systematic planning for conservation is highly regarded but relies on spatially explicit data that are lacking in many areas of conservation concern. The decision support tool Marxan is applied to a reef system in the central Philippines where 30 marine protected areas (MPAs) have been established in communities without much use of biophysical data. The intent was to explore how Marxan might assist with the legally required expansion to protect 15% of marine waters, and how existing MPAs might affect that process. Results show that biophysical information alone did not provide much guidance in identifying patterns of conservation importance in areas where the data are poor. Socioeconomic data were needed to distinguish among possible areas for protection; but here, as elsewhere in marine environments, the availability of such data was very limited. In the final analysis, local knowledge and integrated understanding of socioeconomic realities may offer the best spatially explicit information. The 30 existing MPAs, which encompassed a small proportion of the reef system, did not limit future options in developing a suite of MPAs on a broader scale. Rather, they appeared to generate the support for MPAs that is obligatory for any larger zoning effort. In summary, establishing MPAs based on community-driven criteria has biological and social value, but efforts should be made to collect ecological and socioeconomic data to guide the continued creation of MPAs.

Introduction

In tropical developing countries, the trade off between knowledge acquisition and conservation action—problematic in most marine ecosystems—becomes particularly acute. These nations have rich marine biodiversity, desperate human need, and few resources available for management. Conservation of marine biodiversity in these areas is a grave international concern because tropical marine ecosystems, especially coral reefs, contain some of the greatest species richness in the world [1]. Such marine systems also provide a crucial source of protein and income for coastal communities and for global consumption [2], [3], [4]. Within many countries, human desperation has mounted as population growth, coupled with mismanagement of marine resources and habitat destruction, has led to depleted coastal marine ecosystems [5]. The pressures are about to worsen as more resources are exported globally; one estimate is that 79% of the world's marine production will come from developing countries [6]. Yet few developing countries have the technical or financial capacity to undertake thorough biological research on their marine environments.

Many developing countries are embracing marine protected areas (MPAs) as important management tools [7], [8], [9], [10]. MPAs have been shown in some cases to increase sizes, densities, and biomass of exploited fishes [11], [12]. Despite uncertainty about their effectiveness in general, particularly with respect to fisheries enhancement [13], many national governments have forged ahead with commitments to establish MPAs. This commitment is driven simultaneously by international pressure, as mutlilateral agreements promote MPAs, and by the engagement of coastal communities, which have come to value MPAs in many countries [14].

Developed nation approaches favour science-based decision-making in MPA establishment just as in other conservation actions and resource management situations [15]. Selecting places for protection in a systematic manner, it is argued, ensures that a particular set of conservation objectives is achieved at a minimum cost [15]. The most common conservation objective, in its simplest form, is to represent known components of biodiversity [15], [16], [17], [18], although MPAs are often promoted as a means to enhance fisheries [12], [13], [14], [15], [16], [17], [18], [19]. The most commonly recognized cost of conservation comes in the form of area (i.e., cost is assumed proportional to area) although other inputs can include acquisition, management, transaction, damage and opportunity costs (see [20] for definitions of these costs). Conservation planning tools such as Marxan [17], [18], [19], [20], [21] are designed to assist in the selection of potential MPAs that are representative of known biodiversity, or biodiversity surrogates, whilst minimizing the cost.

Although the value of systematic conservation approaches has been demonstrated in MPAs located in temperate, developed countries [22], [23], [24], relatively few published studies have evaluated this approach in tropical developing countries [25]. Management approaches to conservation are often exported from developed to developing countries—through academic, non-governmental or donor interest—despite the different set of economic, political, and ecological forces operating in these areas. In many developing countries, local managers, municipal leaders, and conservation workers are key players in the placement of MPAs. With limited technical information and relatively few resources for design and management, decisions are usually based on what is politically astute and socioeconomically tolerable, rather than using systematic planning.

A key question in conservation planning is how much time and effort should be invested in taking a systematic approach to marine conservation, in light of limited biophysical data. Most published studies using a systematic approach to marine planning come from developed countries that have better data (e.g., [22], [23], [26], [27]). Such approaches may be less informative in areas that have few data, particularly with an appropriate scale of resolution, and where resources might limit use of even such data as may be available. It may for example, be possible to extract habitat features from satellite imagery (coral reefs, mangroves, seagrass) but the acquisition of such information can be costly and technically challenging. In many regions, available data would be limited to depth contours from basic nautical charts, broad biogeographic regions or a range of latitudes/longitudes. It is unlikely that even local knowledge of species distributions will have been collected and compiled systematically, particularly for non-commercial species.

Although the value of including biophysical data in protected area design has long been recognized, the importance of including socioeconomic data has only recently been highlighted [20], [23], [28], [29], [30], [31]. To maximize the effectiveness of future MPAs, it is increasingly acknowledged that they should be designed to incorporate the important biophysical features while minimizing societal costs. In the marine environment, spatially explicit societal costs include measures of fishing opportunity costs (e.g., catches, effort, CPUE, density of fishing boats) [23], [27], [32], [33], [34], and human population density [35].

In theory, a systematic approach to MPA design should be undertaken before protection is implemented, but this may not be feasible in data-poor regions. One often-raised question is whether existing MPAs—which were not selected using the systematic approach—contribute to, or hinder, the efficient selection of new sites [26], [27], [28], [29], [30], [31], [32], [33], [34]. Previous studies have found that the forced inclusion of existing MPAs results in a more costly (i.e., less efficient) set of MPAs than starting from a blank slate [26], [27], [28], [29], [30], [31], [32], [33], [34]. In developing countries, however, a local and national determination to implement MPAs often means MPAs have previously been established in places and manners that are acceptable to stakeholders. The question of how existing MPAs affect later systematic planning becomes rather important in such circumstances.

The Philippines is a tropical developing country that offers particularly good opportunities for research and action in marine conservation. It lies at the centre of global marine biodiversity [36], has huge human dependency on the ocean, and is very minded to implement MPAs [37], [38]. National legislation decreed in 1998 mandates all municipalities to protect 15% of their waters (Fisheries Code: RA 8550); marine management within 15 km of the coast is devolved to municipalities in the Philippines. Such national policy is compatible with a strong inclination of local communities to implement MPAs. Despite such convergence of national legislation and societal opinion, MPAs still cover only a tiny percentage of the country's marine environment [37]. Momentum for MPAs continues to grow and there is considerable scope for the use of systematic approaches to marine protection.

The purpose of this paper is to two-fold. First, the utility of the most widely used systematic conservation planning tool, Marxan, in identifying areas of conservation priority in the data-poor region of the Danajon Bank, Philippines, is assessed. Available biophysical data are used, datasets that may approximate the socioeconomic cost of establishing MPAs are incorporated, and the ability of Marxan to direct conservation planning efforts is assessed. Second, the effect of existing small no-take MPAs—selected through a people-oriented approach—on the outputs that arise from this systematic planning is assessed.