Anthropogenic Habitats Facilitate Dispersal of an Early Successional Obligate: Implications for Restoration of an Endangered Ecosystem

PLoS One. 2016 Mar 8;11(3):e0148842. doi: 10.1371/journal.pone.0148842. eCollection 2016.

Abstract

Landscape modification and habitat fragmentation disrupt the connectivity of natural landscapes, with major consequences for biodiversity. Species that require patchily distributed habitats, such as those that specialize on early successional ecosystems, must disperse through a landscape matrix with unsuitable habitat types. We evaluated landscape effects on dispersal of an early successional obligate, the New England cottontail (Sylvilagus transitionalis). Using a landscape genetics approach, we identified barriers and facilitators of gene flow and connectivity corridors for a population of cottontails in the northeastern United States. We modeled dispersal in relation to landscape structure and composition and tested hypotheses about the influence of habitat fragmentation on gene flow. Anthropogenic and natural shrubland habitats facilitated gene flow, while the remainder of the matrix, particularly development and forest, impeded gene flow. The relative influence of matrix habitats differed between study areas in relation to a fragmentation gradient. Barrier features had higher explanatory power in the more fragmented site, while facilitating features were important in the less fragmented site. Landscape models that included a simultaneous barrier and facilitating effect of roads had higher explanatory power than models that considered either effect separately, supporting the hypothesis that roads act as both barriers and facilitators at all spatial scales. The inclusion of LiDAR-identified shrubland habitat improved the fit of our facilitator models. Corridor analyses using circuit and least cost path approaches revealed the importance of anthropogenic, linear features for restoring connectivity between the study areas. In fragmented landscapes, human-modified habitats may enhance functional connectivity by providing suitable dispersal conduits for early successional specialists.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Biodiversity*
  • Endangered Species*
  • Gene Flow / physiology
  • Humans
  • Lagomorpha / physiology*
  • Models, Biological*

Grants and funding

Funding for this research was provided by the United States Fish and Wildlife Service, Region 5, Division of Natural Resources, National Wildlife Refuge System; Maine Outdoor Heritage Fund; the National Science Foundation (GSS Grant #1263601); the USDA National Institute of Food and Agriculture – through its McIntire-Stennis Project Number 225575; and the New Hampshire Agricultural Experiment Station. The funders had no role in study design, data collection and analysis, decision to publish, or peparation of the manuscript.