Habitat fragmentation, modification, and loss have been implicated in the decline of many species, including more than 85% of those considered threatened or endangered. Therefore, connectivity, or the ability of organisms to move among habitat patches, is a critical component of landscape health. In addition to influencing the sustainability of wildlife populations and communities, connectivity also contributes to the availability of ecosystem services. The goal of this project was to evaluate terrestrial connectivity across the South Central United States, with a focus on the impact of projected climate and land use changes.
The researchers addressed this goal using a variety of approaches, including evaluating connectivity of major habitat types (grasslands and forests), predicting future changes in landscape connectivity for grassland species, assessing terrestrial vertebrate diversity in relation to habitat loss and fragmentation, and analyzing the combined effects of climate and habitat fragmentation on the distributions of grassland bird species.
They found that connectivity has declined for species with a low to moderate ability to move across the landscape, and that this pattern is expected to continue under future scenarios of land-use change. For grassland birds, the contribution of climate, landscape variables, and their combined effects varied among species, but their combined effects can exceed the independent effects of the two drivers for some species. Thus, the importance of connectivity is expected to increase with the negative implications of climate change for wildlife populations and communities. These results, which are expressed in maps, can be used to inform management decisions and identify future research needs related to terrestrial connectivity within this region.