Landscape-based population viability models demonstrate importance of strategic conservation planning for birds
Abstract
Efforts to conserve regional biodiversity in the face of global climate change, habitat loss and fragmentation will depend on approaches that consider population processes at multiple scales. By combining habitat and demographic modeling, landscape-based population viability models effectively relate small-scale habitat and landscape patterns to regional population viability. We demonstrate the power of landscape-based population viability models to inform conservation planning by using these models to evaluate responses of prairie warbler (Dendroica discolor) and wood thrush (Hylocichla mustelina) populations in the Central Hardwoods Bird Conservation Region to simulated conservation scenarios. We assessed the relative effectiveness of habitat restoration, afforestation, and increased survival and differed placement and levels of effort for implementing those approaches. Population projections of the two species confirmed the potential for large-scale conservation to sustain regional populations. For example, abundances of prairie warblers and wood thrush tripled under afforestation and increased survival scenarios, respectively. Furthermore, responses to conservation actions were driven by interacting local and large-scale population processes such as source–sink interactions and dispersal. Relying on randomly placed habitat conservation was ineffective and potentially counterproductive whereas strategic placements resulted in greater populations and viability of prairie warbler and wood thrush. These models offer a valuable advance in conservation planning because they allow an understanding of the effects of local actions on regional growth, which is necessary for translating regional goals into local actions.