What do black bears, timber rattlesnakes, and Rafinesque’s big-eared bats have in common? They all use bottomland hardwood forests as habitat and they will all be initial focal species for a research project on regional habitat connectivity in the Southeast.
On December 3 and 4, 2012, science coordinators and other staff from the Southeastern LCCs, along with researchers from NC State University, the Wildlands Network, the University of Florida, and the USGS, met to decide on the wildlife species and habitats that will be the focus of the habitat connectivity analysis project funded by the Southeast Climate Science Center. The aim of the research project is to model the connectivity of habitat based on current landscapes and climate, as well as for future climate across the Southeast. The outcome will be a set of maps of habitat connectivity that will identify key linkages for wildlife and key targets for conservation to facilitate range shifts as climate changes. Deciding on the focal species was the first step in this project.
The researchers began the meeting by presenting about the aims connectivity modeling project and related efforts in the Southeast. Nick Haddad, a professor at NC State University, introduced the project and its aims. Ron Sutherland, a scientist with the Wildlands Network, presented on his ongoing habitat connectivity modeling for the South Atlantic LCC. Talks about species distribution modeling, urban growth models, and structured decision making rounded out the initial session of the meeting.
The remainder of the meeting consisted of an informal discussion among LCC staff and the researchers, moderated by Fred Johnson, a scientist with the USGS, and Nick Haddad. The discussion was interesting and fruitful. Much of the dialog focused on the characteristics that would make a species a good focus of this research. Because this is a regional effort, the group agreed that potential focal species would be those that use wide-ranging ecosystems that occur throughout the Southeast. Species that use bottomland hardwood and open pine ecosystems thus emerged as ideal candidates.
Another point of discussion at the meeting was the difference between structural connectivity and functional connectivity. That distinction is an important one in the connectivity research literature too. Structural connectivity refers to the physical relationship between habitat patches, such as the distance between two patches. Functional connectivity refers to the degree to which the landscape facilitates or impedes movement of organisms. Therefore, functional connectivity is a function of structural connectivity as well as the biology of species and organisms, including home range requirements and dispersal ability. The group decided it would be important to incorporate both structural and functional connectivity in this project. Thus, a focus on connectivity for a general habitat type, as well as for a group of species that use that habitat was recommended. Within the focal species, a mix of habitat specialists and habitat generalists was also recommended.
Based on these discussions, the group selected an initial focal habitat type, bottomland hardwood forest communities, along with three focal wildlife species that use that habitat: the black bear, (Ursus americanus), the timber or canebrake rattlesnake (Crotalus horridus) and a bat species, probably the Rafinesque’s big-eared bat (Corynorhinus rafinesquii).
The research team will focus on those species and habitats initially and will report results of modeling to the LCCs. Once habitat connectivity has been modeled for those species, species that use open pine communities will potentially be the second focal group of species for the project.