A quantitative approach for the design of robust and cost-effective conservation policies under uncertain climate change: The case of grasshopper conservation in Schleswig-Holstein, Germany.

Climate is a major determinant of the world's distribution of biodiversity and species ranges are expected to shift as the climate changes. For conservation policies to be cost-effective in the long run these changes need to be taken into account. To some extent, policies can be adapted over time, but transaction costs, lock-in effects and path dependence limit the extent to which such adaptation is possible. Thus it is desirable that conservation policies be designed so that they are cost-effective in the long run even without future adaptations. Given that the future climate change is highly uncertain, the policies need to be robust to climatic uncertainty. In this paper we present an approach for the robustness analysis with regard to the cost-effectiveness of conservation policies in the face of uncertain climate change. The approach is applied to the conservation of a grasshopper species in the German federal state of Schleswig-Holstein. For the assessment of the cost-effectiveness of considered policies we develop a climate-ecological-economic model. We show that in the near future all considered policies have a similar level of robustness, while in the more distant future the policies differ substantially in their robustness and a trade-off emerges between the expected performance and robustness of a policy.

An economic evaluation framework for land-use-based conservation policy instruments in a changing climate.

Climate change is a key threat to biodiversity. To conserve species under climate change, ecologists and conservation scientists suggest 2 main conservation strategies regarding land use: supporting species' range shifts to enable it to follow its climatic requirements by creating migration pathways, such as corridors and stepping stones, and conserving climate refugia (i.e., existing habitat areas that are somewhat buffered from climate change). The policy instruments that could be used to implement these conservation strategies have yet to be evaluated comprehensively from an economic perspective. The economic analyses of environmental policy instruments are often based on ecological effectiveness and cost-effectiveness criteria. We adapted these general criteria to evaluate policy instruments for species' conservation under climate change and applied them to a conceptual analysis of land purchases, offsets, and conservation payments. Depending on whether the strategy supporting species' range shifts or conserving climate refugia is selected, the evaluation of the policy instruments differed substantially. For example, to ensure ecological effectiveness, habitat persistence over time was especially important for climate refugia and was best achieved by a land-purchase policy instrument. In contrast, for the strategy supporting range shifts to be ecologically effective, a high degree of flexibility in the location of conserved sites was required to ensure that new habitat sites can be created in the species' new range. Offset programs were best suited for that because the location of conservation sites can be chosen comparatively freely and may also be adapted over time.

Un Marco de Trabajo de Análisis Económico para los Instrumentos de Políticas de Conservación Basada en el Uso de Suelo en un Clima Cambiante Resumen El cambio climático es una amenaza muy importante para la biodiversidad. Para conservar a las especies durante el cambio climático, los ecólogos y los científicos de la conservación sugieren dos estrategias principales de conservación con respecto al uso de suelo: asistir los cambios de distribución de las especies para permitirles seguir los requerimientos climáticos creando rutas de migración, como los corredores ecológicos y los trampolines, y conservar los refugios climáticos (es decir, las áreas existentes de hábitat que están de cierta manera protegidas del cambio climático). Los instrumentos de políticas que podrían usarse para implementar estas estrategias de conservación todavía no han sido evaluados de manera exhaustiva desde una perspectiva económica. Los análisis económicos de los instrumentos de políticas ambientales están basados con frecuencia en la efectividad ecológica y los criterios de rentabilidad. Adaptamos estos criterios generales para evaluar los instrumentos de políticas para la conservación de las especies durante el cambio climático y los aplicamos a los análisis conceptuales de la compra de tierras, compensaciones y pagos por conservación. La evaluación de los instrumentos de políticas difirió sustancialmente dependiendo de si se seleccionaba la estrategia de asistir los cambios de distribución de las especies o la de conservar los refugios climáticos. Por ejemplo, para asegurar la efectividad ecológica, la persistencia del hábitat con el tiempo era de importancia especial para los refugios climáticos y se conseguía de mejor manera mediante un instrumento de políticas de compra de tierras. Por otro lado, para que la estrategia de asistir los cambios de distribución fuera ecológicamente efectiva, se requirió un nivel elevado de flexibilidad en la ubicación de sitios conservados para asegurar que se puedan crear sitios nuevos de hábitat dentro de la distribución nueva de la especie. Los programas de compensaciones fueron mejor indicados para lo anterior pues la ubicación de los sitios de conservación se puede elegir libremente en comparación y también puede irse adaptando con el tiempo.

Cost-effectiveness of conservation payment schemes for species with different range sizes.

Payments to compensate landowners for carrying out costly land-use measures that benefit endangered biodiversity have become an important policy instrument. When designing such payments, it is important to take into account that spatially connected habitats are more valuable for many species than isolated ones. One way to incentivize provision of connected habitats is to offer landowners an agglomeration bonus, that is, a bonus on top of payments they are receiving to conserve land if the land is spatially connected. Researchers have compared the cost-effectiveness of the agglomeration bonus with 2 alternatives: an all-or-nothing, agglomeration payment, where landowners receive a payment only if the conserved land parcels have a certain level of spatial connectivity, and a spatially homogeneous payment, where landowners receive a payment for conserved land parcels irrespective of their location. Their results show the agglomeration bonus is rarely the most cost-effective option, and when it is, it is only slightly better than one of the alternatives. This suggests that the agglomeration bonus should not be given priority as a policy design option. However, this finding is based on consideration of only 1 species. We examined whether the same applied to 2 species, one for which the homogeneous payment is best and the other for which the agglomeration payment is most cost-effective. We modified a published conceptual model so that we were able to assess the cost-effectiveness of payment schemes for 2 species and applied it to a grassland bird and a grassland butterfly in Germany that require the same habitat but have different spatial-connectivity needs. When conserving both species, the agglomeration bonus was more cost-effective than the agglomeration and the homogeneous payment; thus, we showed that as a policy the agglomeration bonus is a useful conservation-payment option.

A conceptual analysis of the application of tradable permits to biodiversity conservation.

Tradable permits have been applied in many areas of environmental policy and may be a response to increasing calls for flexible conservation instruments that successfully conserve biodiversity while allowing for economic development. The idea behind applying tradable permits to conservation is that developers wishing to turn land to economic purposes, thereby destroying valuable habitat, may only do so if they submit a permit to the conservation agency showing that habitat of at least the equivalent ecological value is restored elsewhere. The developer himself does not need to carry out the restoration, but may buy a permit from a third party, thus allowing a market to emerge. Nevertheless, the application of tradable permits to biodiversity conservation is a complex issue because destroyed and restored habitats are likely to differ. There may be various trade-offs between the ecological requirements that destroyed and restored habitats be as similar as possible, and the need for a certain level of market activity to have a functioning trading system. The success of tradable permits as an instrument for reconciling the conflicts between economic development and conservation depends on the existence of certain economic, institutional, and ecological preconditions, for example, a functioning institutional framework, sufficient expert knowledge, and adequate monitoring and enforcement mechanisms.

Designing cost-effective payments for conservation measures to generate spatiotemporal habitat heterogeneity.

Many endangered species depend on certain types of agricultural or other forms of human land use. To conserve such species, schemes are set up in which land users receive payments for voluntarily managing their land in a biodiversity-enhancing manner. We developed a model-based framework for designing cost-effective payment schemes that generate spatiotemporal habitat heterogeneity to maximize the survival of multiple species under budget constraints. The framework integrates ecological and economic knowledge and consists of the derivation of an ecological benefit function and a budget function that are then combined to determine the cost-effective degree of spatiotemporal habitat heterogeneity. The ecological benefit function considers the timing of conservation measures, the induced habitat dynamics, and different degrees of substitutability among species. The budget function considers that the conservation agency may lack information about land users' individual conservation costs and personal attitudes and that land users can choose among different conservation measures. We applied the framework to a case study of grassland management, where the survival of three endangered species protected by the EU Habitats Directive depends on different types of land use. The lack of information available to the agency and the choice options of land users reduced the amount of conservation that can be financed with a given budget. Neglecting such findings may lead to an overestimation of the benefits of conservation programs.

Integrating economic costs into the analysis of flexible conservation management strategies.

Flexible conservation management, where measures (e.g., mowing of meadows, removing invasive species) are selected in each decision period depending on the current state of the ecological system, is generally perceived as superior to fixed management, where the same measure is applied in each decision period independent of the current state of the system. In past comparisons of fixed and flexible conservation strategies the additional costs that arise only in flexible strategies have usually been ignored. In this paper, we present a framework to integrate costs of flexible management into the evaluation of flexible conservation strategies. Using the example of an endangered butterfly species we demonstrate that the costs of flexible management may reverse the rank order of flexible and fixed conservation strategies, such that fixed strategies may lead to better ecological results than flexible ones for the same financial budget.

Ecological-economic modeling for biodiversity management: potential, pitfalls, and prospects.

Ecologists and economists both use models to help develop strategies for biodiversity management. The practical use of disciplinary models, however can be limited because ecological models tend not to address the socioeconomic dimension of biodiversity management, whereas economic models tend to neglect the ecological dimension. Given these shortcomings of disciplinary models, there is a necessity to combine ecological and economic knowledge into ecological-economic models. It is insufficient if scientists work separately in their own disciplines and combine their knowledge only when it comes to formulating management recommendations. Such an approach does not capture feedback loops between the ecological and the socioeconomic systems. Furthermore, each discipline poses the management problem in its own way and comes up with its own most appropriate solution. These disciplinary solutions, however, are likely to be so different that a combined solution considering aspects of both disciplines cannot be found. Preconditions for a successful model-based integration of ecology and economics include (1) an in-depth knowledge of the two disciplines, (2) the adequate identification and framing of the problem to be investigated, and (3) a common understanding between economists and ecologists of modeling and scale. To further advance ecological-economic modeling the development of common benchmarks, quality controls, and refereeing standards for ecological-economic models is desirable.