Optimization approaches intended to inform how conservation funding should be allocated gloss over challenges inherent in implementing recommendations. To be implemented, recommendations have to work within existing institutional structures. We illustrate two ways of accounting for institutional structure in spatial conservation planning. We focus on prioritizing future habitat protection for biodiversity in the coterminous US, paying particular attention to the role of states in implementing national priorities. As a benchmark, we examine what locations would be priorities for additional protection if conservation funds could be freely allocated anywhere. Our optimization integrates information on terrestrial vertebrate species, costs, future conversion, and the ecological value of private land. We contrast an optimization that ignores institutional structure with two others. First, we focus on where funding to support conservation originates, using philanthropic support to The Nature Conservancy (TNC) as an example. We examine the consequences of only having limited flexibility to move funding between states. Next, we examine how interactions among conservation actors affect priorities. Specifically, we examine a situation where a national program allocates funds to states, which then implement conservation programs. We pay particular attention to how differences in the objectives that conservation actors pursue affect what locations receive protection.
Results/Conclusions
If conservation funding can be moved around freely, locations where concentrations of species are threatened with future habitat conversion, like counties surrounding Austin, Texas, emerge as consistent priorities for protection. However, conservation organizations may be limited in their ability to concentrate funding into such locations. For example, TNC’s recent expenditures on land protection partly reflect variation in their fund-raising, in which some states (California and New York) give at nine times the median rate. We show how institutional constraints that limit how freely conservation funding can be moved around impact the biodiversity gains available from habitat protection programs. We do so when assuming actors share the same overall conservation objective. Then, we illustrate a hierarchical optimization approach that can account for differences between conservation actors regarding what aspects of biodiversity they most value. We apply it to examine a conservation program in which funding is first allocated to states and states, in turn, decide where to protect within their boundaries. Ignoring institutional structure in spatial planning tools leads to an over-estimation of possible conservation gains and can risk ineffective priorities being recommended. We also show how a national funding program could mitigate some of these effects.