Spatial Conservation Priorities Research Articles

Defining spatial conservation priorities in the face of land-use and climate change

Creating and managing protected areas is critical to ensure the persistence of species but dynamic threats like land-use change and climate change may reduce the effectiveness of protected areas planned under a static approach. Here we defined spatial priorities for the conservation of non-flying mammals inhabiting the Cerrado Biodiversity Hotspot, Brazil, that overcome the likely impacts of land-use and climate change to this imperiled fauna. We used cutting-edge methods of species distribution models combining thousands of model projections to generate a comprehensive ensemble of forecasts that shows the likely impacts of climate change in mammal distribution. We also generate a future land-use model that indicates how the region would be impacted by habitat loss in the future. We then used our models to propose priority sites for mammal conservation minimizing species climate-forced dispersal distance as well as the mean uncertainty associated to species distribution models and climate models. At the same time, our proposal maximizes complementary species representation across the existing network of protected areas. Including land-use changes and model uncertainties in the planning process changed significantly the spatial distribution of priority sites in the region. While the inclusion of land-use models altered the spatial location of priority sites at the regional scale, the effects of climate change tended to operate at the local scale. Our solutions already include possible dispersal corridors linking current and future priority sites for mammal conservation, as well as a formal risk analysis based on planning uncertainties. We hope to provide decision makers with conservation portfolios that could be negotiated at the decision level.

Species vulnerability to climate change: impacts on spatial conservation priorities and species representation

Species vulnerability to climate change: impacts on spatial conservation priorities and species representation

Do hunters tell the truth? Evaluation of hunters' spring pair density estimates of the grey partridge Perdix perdix

Hunters' estimates of pair densities of the grey partridge Perdix perdix as derived from an annual questionnaire survey (‘Game Survey Lower Saxony’, WTE) were evaluated by comparison with detailed ground‐truthing censuses in 123 randomly chosen hunting districts representing 63,847 ha potential grey partridge habitat. Estimates and evaluation‐census‐densities were highly significantly correlated. The median of the hunters' estimate errors, disregarding the direction of the relative discrepancy, was 24.2%. Hunters underestimated the density per 100 ha potential habitat by 0.16 breeding pairs on average. The discrepancy increased with higher grey partridge densities and increasing size of the hunting district. The satisfactory agreement between the estimates of the hunters, in most cases local farmers, and the evaluation survey is explained by their comprehensive year‐round presence through their hunting, farming but also their leisure activities and their special interest in this charismatic bird combined with its site fidelity. We recommend the consultation of WTE data as a valuable source of basic information on distribution and abundance of grey partridges to identify spatial conservation priorities, to justify conservation initiatives and to adapt management practices.

Species vulnerability to climate change: impacts on spatial conservation priorities and species representation

AbstractClimate change may shrink and/or shift plant species ranges thereby increasing their vulnerability and requiring targeted conservation to facilitate adaptation. We quantified the vulnerability to climate change of plant species based on exposure, sensitivity and adaptive capacity and assessed the effects of including these components in complementarity‐based spatial conservation prioritisation. We modelled the vulnerability of 584 native plant species under three climate change scenarios in an 11.9 million hectare fragmented agricultural region in southern Australia. We represented exposure as species' geographical range under each climate change scenario as quantified using species distribution models. We calculated sensitivity as a function of the impact of climate change on species' geographical ranges. Using a dispersal kernel, we quantified adaptive capacity as species' ability to migrate to new geographical ranges under each climate change scenario. Using Zonation, we assessed the impact of individual components of vulnerability (exposure, sensitivity and adaptive capacity) on spatial conservation priorities and levels of species representation in priority areas under each climate change scenario. The full vulnerability framework proved an effective basis for identifying spatial conservation priorities under climate change. Including different dimensions of vulnerability had significant implications for spatial conservation priorities. Incorporating adaptive capacity increased the level of representation of most species. However, prioritising sensitive species reduced the representation of other species. We conclude that whilst taking an integrated approach to mitigating species vulnerability to climate change can ensure sensitive species are well‐represented in a conservation network, this can come at the cost of reduced representation of other species. Conservation planning decisions aimed at reducing species vulnerability to climate change need to be made in full cognisance of the sensitivity of spatial conservation priorities to individual components of vulnerability, and the trade‐offs associated with focussing on sensitive species.

Performance and Consistency of Indicator Groups in Two Biodiversity Hotspots

BackgroundIn a world limited by data availability and limited funds for conservation, scientists and practitioners must use indicator groups to define spatial conservation priorities. Several studies have evaluated the effectiveness of indicator groups, but still little is known about the consistency in performance of these groups in different regions, which would allow their a priori selection.Methodology/Principal FindingsWe systematically examined the effectiveness and the consistency of nine indicator groups in representing mammal species in two top-ranked Biodiversity Hotspots (BH): the Brazilian Cerrado and the Atlantic Forest. To test for group effectiveness we first found the best sets of sites able to maximize the representation of each indicator group in the BH and then calculated the average representation of different target species by the indicator groups in the BH. We considered consistent indicator groups whose representation of target species was not statistically different between BH. We called effective those groups that outperformed the target-species representation achieved by random sets of species. Effective indicator groups required the selection of less than 2% of the BH area for representing target species. Restricted-range species were the most effective indicators for the representation of all mammal diversity as well as target species. It was also the only group with high consistency.Conclusions/SignificanceWe show that several indicator groups could be applied as shortcuts for representing mammal species in the Cerrado and the Atlantic Forest to develop conservation plans, however, only restricted-range species consistently held as the most effective indicator group for such a task. This group is of particular importance in conservation planning as it captures high diversity of endemic and endangered species.

Addressing longitudinal connectivity in the systematic conservation planning of fresh waters

Summary1. Freshwater conservation has received less attention than its terrestrial or marine counterparts. Given the accelerated rate of change and intensive human use that freshwater ecosystems are submitted to, it is urgent to focus more attention on fresh waters. Existing conservation planning tools – such as Marxan – need to be modified to account for the special nature of these systems. Connectivity plays a key role in freshwater ecosystems. Threats are mediated along river corridors, and the condition of the entire catchment influences river biodiversity downstream. This needs to be considered in conservation planning.2. The probabilities of occurrence of nine native freshwater fish species in a Mediterranean river basin, obtained from Multivariate Adaptive Regression Splines‐ Generalized Linear Model (MARS‐GLM) models, were used as features to develop spatial conservation priorities. The priorities accounted for complementarity and spatial design issues.3. To deal with the connected nature of rivers, we modified Marxan’s boundary length penalty, avoiding the selection of isolated planning units and forcing the inclusion of closer upstream areas. We introduced ‘virtual boundaries’ between non‐headwater stream segments and added distance‐weighted penalties to the overall connectivity cost (CP) when stream segments upstream of the selected planning units are not selected.4. This approach to prioritising connectivity is concordant with ecological theory, as it considers the natural and roughly exponential decay of upstream influences with distance. It accounts for the natural capacity of rivers to mitigate impacts when designing reserves. When connectivity was not emphasised, Marxan prioritised natural corridors for longitudinal movements. In contrast, whole sub‐basins were prioritised when connectivity was emphasised. Changing the relative emphasis on connectivity substantially changed the spatial prioritisation; our conservation investment could move from one basin to another.5. Our novel approach to dealing with directional connectivity enables managers of freshwater systems to set ecologically meaningful spatial conservation priorities.

Comparing Spatially Explicit Ecological and Social Values for Natural Areas to Identify Effective Conservation Strategies

Consideration of the social values people assign to relatively undisturbed native ecosystems is critical for the success of science-based conservation plans. We used an interview process to identify and map social values assigned to 31 ecosystem services provided by natural areas in an agricultural landscape in southern Australia. We then modeled the spatial distribution of 12 components of ecological value commonly used in setting spatial conservation priorities. We used the analytical hierarchy process to weight these components and used multiattribute utility theory to combine them into a single spatial layer of ecological value. Social values assigned to natural areas were negatively correlated with ecological values overall, but were positively correlated with some components of ecological value. In terms of the spatial distribution of values, people valued protected areas, whereas those natural areas underrepresented in the reserve system were of higher ecological value. The habitats of threatened animal species were assigned both high ecological value and high social value. Only small areas were assigned both high ecological value and high social value in the study area, whereas large areas of high ecological value were of low social value, and vice versa. We used the assigned ecological and social values to identify different conservation strategies (e.g., information sharing, community engagement, incentive payments) that may be effective for specific areas. We suggest that consideration of both ecological and social values in selection of conservation strategies can enhance the success of science-based conservation planning.

Biodiversity offsets: adding to the conservation estate, or ‘no net loss’?

The Western Cape province of South Africa contains globally unique biodiversity, to which pressure for economic growth and development poses a significant threat. Legal and planning frameworks support biodiversity conservation and biodiversity offsets. Biodiversity plans at different scales provide a clear indication of spatial priorities for conservation. In this context, a draft guideline for biodiversity offsets in the Western Cape has been developed (DEA&DP, 2007) which introduces biodiversity offsets as an integral part of the regulatory environmental impact assessment and development authorization process. The approach focuses on area- and monetary-based compensation to secure and manage priority areas in the long term. The emphasis is on adding priority habitats to the conservation estate, rather than on achieving ‘no net loss’ in the strictest sense. This paper explains how the context of the Western Cape has shaped its approach to biodiversity offsets: the political, socioeconomic and institutional characteristics are as important in designing a guideline for offsets as biodiversity considerations. The paper notes key challenges facing the province in implementing the guideline.

The Landscape Species Approach: spatially-explicit conservation planning applied in the Adirondacks, USA, and San Guillermo-Laguna Brava, Argentina, landscapes

The Landscape Species Approach is a framework developed by the Wildlife Conservation Society for planning landscape-scale conservation based on a suite of focal species. The approach has so far been implemented at 12 terrestrial and two marine sites. We demonstrate the approach using two sites, the Adirondack Park, USA, and San Guillermo-Laguna Brava Landscape, Argentina. We describe the spatially explicit components, including steps to map the attainable (Biological Landscape), current, and future distribution of Landscape Species, human activities (Human Landscapes) and their impacts on Landscape Species, the possible impacts of conservation actions (Conservation Landscapes), and a procedure to set spatial conservation priorities. We discuss advantages and innovations of the approach, including how it incorporates both vulnerability of biodiversity and possible recovery. Finally, we discuss improvements that can be made to the approach, costs, and implications for conservation at the two sites.

Developing products for conservation decision‐making: lessons from a spatial biodiversity assessment for South Africa

ABSTRACTSouth Africa's first national assessment of spatial priorities for biodiversity conservation, released in 2005, aimed to identify conservation priority areas for mainstreaming into all sectors at national and provincial scales. This National Spatial Biodiversity Assessment (NSBA) was based on a planning for implementation approach in order to deliver defensible products useful to decision‐makers. The NSBA aimed to produce a map of broad‐scale priority areas for future finer‐scale assessment and conservation action. This map summarized information on species, ecosystems, ecological processes, and the pressures they face from human activities. Owing to the complexity of the priority area map, two additional user‐friendly products — maps of ecosystem status and protection levels — were developed. These products represented the habitat loss and protected area coverage of South Africa's ecosystems relative to their conservation targets. A year after release, we reflect on the NSBA process, products and uptake by implementing agencies (with a specific focus on the terrestrial biodiversity assessment) in order to contribute to the growing body of documented best practice in conservation planning. The ecosystem status product has been widely used at national and provincial scales due in large to its clear and compelling message. The protection level and overall priority map have also witnessed uptake, the former in guiding the expansion of protected areas and the latter as an integrated map of national biodiversity status. The strong collaboration of local planners and implementers with in‐depth experience of biodiversity assessment, using a systematic approach and focusing on communicating a few high level messages, appears to have contributed to the initial, successful uptake of the NSBA. We conclude with a call to address data and monitoring shortcomings before the next NSBA in 2010.

Biodiversity and endemism mapping as a tool for regional conservation planning – case study of the Pleurothallidinae (Orchidaceae) of the Andean rain forests in Bolivia

Analyses of species diversity and endemism patterns provide vital inputs for conservation planning. Therefore, it is an important dilemma of biodiversity conservation that in very diverse but poorly studied tropical countries those patterns can hardly be considered. Consequently, there is an urgent need to develop prediction models that make the best use of existing data on species distribution and that can give hints on spatial conservation priorities. This paper presents the results of a pilot study on the diversity of the orchid subtribe Pleurothallidinae (331 mapped species) in the Andean rain forests of Bolivia. Results of a taxon-based mapping methodology, using abiotic (humidity and temperature, the latter indicated by altitude) and historical factors (taken into account as distance from collection localities) that determine species ranges, are compared with outcomes of an inventory-based mapping approach. The patterns of taxon-based diversity and endemism show a strong correlation with the distribution of sample localities. The inventory-based approach is more reliable, but it is interesting to apply both mapping methods in order to make a critical interpretation and comparison that facilitates some valuable conservation recommendations. We end with concrete conclusions for conservation planning and action.

Using higher-taxon richness as a surrogate for species richness: II. Local applications

Recent analyses confirm that urgent attempts to catalogue the distribution of biological diversity may be facilitated by focusing at the level of genera or families rather than species. However, questions remain over the application of higher-taxon surveys to identify networks of priority areas for conservation action. Is the close spatial match between species and higher-taxon richness at global and regional scales re-iterated when sites are locally distributed? How much money is saved by the higher-taxon approach? And how does using genus or family information affect the efficiency with which spatial priorities for conservation are identified? We examined these issues using data on the diversity of woody plants in Sri Lankan forests. We found that at this local scale, the family and particularly generic richness of sites was closely linked to their species richness, independently of variation in site size. Moreover, fieldwork in an additional forest showed that targeting woody plant genera and families rather than species reduced survey costs by a minimum of 60% and 85% respectively. Most importantly, while using family data in site-selection algorithms led to the loss from reserve networks of around 7-10% of woody plant species, using genera rather than species had virtually no effect on the representation of species in priority sites. These results thus confirm that judicious use of the higher-taxon approach is indeed a valuable technique for improving the cost effectiveness of field surveys for local conservation planning in the tropics.