Heterogeneous landscapes and fluctuating environmental conditions can affect species dispersal, population genetics, and genetic structure, yet understanding how biotic and abiotic factors affect population dynamics in a fluctuating environment is critical for species management. We evaluated how spatio-temporal habitat connectivity influences dispersal and genetic structure in a population of boreal chorus frogs (Pseudacris maculata) using a landscape genetics approach. We developed gravity models to assess the contribution of various factors to the observed genetic distance as a measure of functional connectivity. We selected (a) wetland (within-site) and (b) landscape matrix (between-site) characteristics; and (c) wetland connectivity metrics using a unique methodology. Specifically, we developed three networks that quantify wetland connectivity based on: (i) P. maculata dispersal ability, (ii) temporal variation in wetland quality, and (iii) contribution of wetland stepping-stones to frog dispersal. We examined 18 wetlands in Colorado, and quantified 12 microsatellite loci from 322 individual frogs. We found that genetic connectivity was related to topographic complexity, within- and between-wetland differences in moisture, and wetland functional connectivity as contributed by stepping-stone wetlands. Our results highlight the role that dynamic environmental factors have on dispersal-limited species and illustrate how complex asynchronous interactions contribute to the structure of spatially-explicit metapopulations.
|Title||How spatio-temporal habitat connectivity affects amphibian genetic structure|
|Authors||Alexander G. Watts, P Schlichting, S Billerman, B Jesmer, S Micheletti, M.-J. Fortin, W. C. Funk, P Hapeman, Erin L. Muths, M.A. Murphy|
|Publication Subtype||Journal Article|
|Series Title||Frontiers in Genetics|
|Record Source||USGS Publications Warehouse|
|USGS Organization||Fort Collins Science Center|
Erin Muths, Ph.D.
Erin Muths, Ph.D.