Population connectivity in voles (Microtus sp.) as a gauge for tall grass prairie restoration in midwestern North America

PLoS One. 2021 Dec 9;16(12):e0260344. doi: 10.1371/journal.pone.0260344. eCollection 2021.

Abstract

Ecological restoration can promote biodiversity conservation in anthropogenically fragmented habitats, but effectiveness of these management efforts need to be statistically validated to determine 'success.' One such approach is to gauge the extent of recolonization as a measure of landscape permeability and, in turn, population connectivity. In this context, we estimated dispersal and population connectivity in prairie vole (Microtus ochrogaster; N = 231) and meadow vole (M. pennsylvanicus; N = 83) within five tall-grass prairie restoration sites embedded within the agricultural matrix of midwestern North America. We predicted that vole dispersal would be constrained by the extent of agricultural land surrounding restored habitat patches, spatially isolating vole populations and resulting in significant genetic structure. We first employed genetic assignment tests based on 15 microsatellite DNA loci to validate field-derived species-designations, then tested reclassified samples with multivariate and Bayesian clustering to assay for spatial and temporal genetic structure. Population connectivity was further evaluated by calculating pairwise FST, then potential demographic effects explored by computing migration rates, effective population size (Ne), and average relatedness (r). Genetic species assignments reclassified 25% of initial field identifications (N = 11 M. ochrogaster; N = 67 M. pennsylvanicus). In M. ochrogaster population connectivity was high across the study area, reflected in little to no spatial or temporal genetic structure. In M. pennsylvanicus genetic structure was detected, but relatedness estimates identified it as kin-clustering instead, underscoring social behavior among populations rather than spatial isolation as the cause. Estimates of Ne and r were stable across years, reflecting high dispersal and demographic resilience. Combined, these metrics suggest the agricultural matrix is highly permeable for voles and does not impede dispersal. High connectivity observed confirms that the restored landscape is productive and permeable for specific management targets such as voles and also demonstrates population genetic assays as a tool to statistically evaluate effectiveness of conservation initiatives.

Publication types

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

MeSH terms

  • Animals
  • Arvicolinae / classification*
  • Arvicolinae / genetics
  • Arvicolinae / physiology*
  • Bayes Theorem
  • Environmental Restoration and Remediation
  • Female
  • Gene Flow
  • Genetic Variation
  • Genetics, Population
  • Grassland
  • Microsatellite Repeats*
  • North America
  • Population Density
  • Population Dynamics

Grants and funding

The U.S. Fish and Wildlife Service (USFWS) Federal Aid in Wildlife Restoration Program, as administered by the Illinois Department of Natural Resources (IDNR), provided funding for this project (awarded to MRD and MED). Additional funding was provided by endowments through University of Arkansas/ Fayetteville to MRD (Bruker Professor of Life Sciences) and MED (21st Century Chair in Global Change Biology).