Dynamically-Based Criteria for the Identification of Optimal Bioreserve Networks

Abstract

The use of “surrogate” design criteria (such as size or connectedness) to evaluate potential bioreserve network alternatives is attractive because they can be relatively straightforward to measure. However, to promote the persistence of a focal species, a higher level of biological detail may be used to derive specific design criteria for the species of interest. But just as for surrogate criteria, no single best criterion is likely to arise. Here, a set of mechanistic equations describing the dynamics of hawks and voles in a hypothetical landscape is used to derive design criteria for a reserve network. Multiobjective Integer Programming (MOIP) then identifies reserve network alternatives that reflect the tradeoffs between the objectives. When choosing from only five potential patches for inclusion in the network, in four of five cases a single design optimized the design objectives simultaneously. When choosing from ten patches, in all five cases there were conflicts between the objectives, but in two of five cases, there were optimal intermediate solutions along the tradeoff surface between the objectives. When resources allow, a more detailed description of the species of conservation interest may be used to develop reserve design criteria that are likely to promote persistence. MOIP can then be used to evaluate potential compromises between the criteria.