Authors: Wätzold, Frank; Gerling, Charlotte;Keuler, Klaus ;Sturm, Astrid;Leins, Johannes ;Drechsler, Martin;

Under climate change, current conservation efforts may become less effective and cost-effective as the effectiveness and costs of conservation sites and measures may change. Flexible conservation policy instruments that allow for the adaptation of conservation measures (“local flexibility”) and sites (“spatial flexibility”) may improve the cost-effectiveness of conservation under climate change. However, trade-offs between local and spatial flexibility may exist depending on the policy instrument. Here, we analyse land purchase and long-term individual conservation contracts. We develop a model that integrates ecological, economic and climated data and considers the different degrees of flexibility of the two policy instruments. We apply the model to the conservation of the large marsh grasshopper (Stethophyma grossum) on agricultural grasslands in a case study area (parts of Schleswig-Holstein, Northern Germany) and consider climate scenarios RCP4.5 and RCP8.5 for the periods 2020-2039 and 2060-2079. In the case study, land purchase has a higher cost-effectiveness than conservation contracts if the conservation agency is able to generate profits from extensive land use. Local flexibility only plays a small role, but spatial flexibility is important when the available budget is small and only allows for small extensions of the conservation network to adapt to climate change.