Sea level rise and land use change are set to disrupt connectivity in the Southeastern US

The Southeastern United States contains many rich and diverse ecosystems that serve as global hotspots for herpetofauna, freshwater mussels and fishes, and endemic flora. Many of these landscapes are also among the fastest developing areas in the nation. These landuse changes produce negative consequences for many native wildlife species that are increasingly embedded in human dominated settings. In the coastal plain ecoregions of the Southeastern U.S., rising sea levels may further fragment habitats while forcing animals to move inland.

We studied the fragmenting effects of urbanization and sea level changes for a suite of species by modeling connectivity at multiple spatial scales. We chose species to model based on conservation need (listed by state), and also on movement and dispersal requirements that, when considered collectively, might provide insights about the landscape as a whole. Using these models, we estimated connectivity in the contemporary landscape and forecasted future connectivity into the year 2100.

Leonard_connectivity_copyrightWe found that the future southeastern landscape will contain fewer large and connected habitat cores for our species (-41%), and that on average future cores will be smaller than contemporary ones (-35%).  Decreases were not uniform across the region and thus, the impacts of changing landscape connectivity patterns to our species were more severe in particular places. Areas that underwent the most change were the Piedmont, Southeastern Plains, and Southern Coastal Plains ecoregions. In general, we found a future landscape connectivity that was more evenly fragmented as compared to contemporary areas of high and low connectivity. In addition, areas of future connectivity value were typically found at higher elevations and further inland. These changes will increase the need for wildlife mitigation techniques and restoration to increase landscape permeability.

By examining changing landscape connectivity patterns, we can proactively plan for and buffer out enduring features that may be critical connectors and corridors in the future. This study highlights areas that will increase in conservation importance through time and may require conservation action to prevent the loss of connectivity functions. These areas include:

  • River and riparian corridors connecting the southern Appalachian Mountains to the coastal plain ecoregions.
  • Outer coastal plain forests that may act as a refuge to animals escaping sea-level rise.
  • Unfragmented forests in the southeastern Sandhills and Piedmont ecoregions that will undergo large urbanization pressures and yet serve as primary pathways to higher elevation and cooler climates.

Resources

Leonard, P. B., R. W. Sutherland, R. F. Baldwin, D. A. Fedak, R. G. Carnes, and A. P. Montgomery. 2016. Landscape connectivity losses due to sea level rise and land use change. Animal Conservation. DOI: 10.1111/acv.12289.

2016-10-14T10:10:21+00:00 July 31st, 2016|

About the Author:

Paul Leonard
Paul Leonard is a postdoctoral fellow at Clemson University in the Department of Forestry and Environmental Conservation. He works with multiple conservation collaboratives and NGOs on landscape-scale conservation planning. You can read more about his work at conservationcomputing.com.