Conference Agenda

Climate change and the ongoing homogenisation of agricultural landscapes pose major threats to biodiversity. Increasing climatic variability complicates the alignment of land-use schedules (e.g., mowing regimes) with the species’ life cycles (e.g., reproduction period of meadow birds), while landscape homogenisation reduces the diversity of living conditions for species. Adaptive and spatially differentiated policies are increasingly discussed to address these challenges. We develop a generic model of a grassland that is used for hay production and is habitat of a number of meadow birds. Three strategies are compared with respect to their efficiency, measured by the sum of an economic benefit and a weighted biodiversity benefit. The strategies differ by their adaptability and by their specificity with respect to the species’ life cycles. Flexibility is shown to pay off only if the climatic variation is large compared to the measurement error that occurs in the prediction of the current year’s ecological and economic effects of the different mowing regimes. An increasing level of the regulator’s risk aversion or a decreasing weight on biodiversity, in contrast, favour the species-unspecific strategy which uses no ecological or economic information at all. Noting that our analysis ignores the cost of information acquisition, implementation costs and other transaction costs, we conclude that higher levels of complexity and target accuracy do not always reflect in a more efficient conservation of biodiversity. Instead, the different pros and cons of different strategies need to be weighted carefully in the light of the present conservation problem.