Gene flow of a forest-dependent bird across a fragmented landscape
Date
2015
Authors
Adams, Rachael V.
Burg, Theresa M.
Journal Title
Journal ISSN
Volume Title
Publisher
Public Library of Science
Abstract
Habitat loss and fragmentation can affect the persistence of populations by reducing connectivity
and restricting the ability of individuals to disperse across landscapes. Dispersal
corridors promote population connectivity and therefore play important roles in maintaining
gene flow in natural populations inhabiting fragmented landscapes. In the prairies, forests
are restricted to riparian areas along river systems which act as important dispersal corridors
for forest dependent species across large expanses of unsuitable grassland habitat.
However, natural and anthropogenic barriers within riparian systems have fragmented
these forested habitats. In this study, we used microsatellite markers to assess the finescale
genetic structure of a forest-dependent species, the black-capped chickadee (Poecile
atricapillus), along 10 different river systems in Southern Alberta. Using a landscape genetic
approach, landscape features (e.g., land cover) were found to have a significant effect on
patterns of genetic differentiation. Populations are genetically structured as a result of natural
breaks in continuous habitat at small spatial scales, but the artificial barriers we tested do
not appear to restrict gene flow. Dispersal between rivers is impeded by grasslands, evident
from isolation of nearby populations (~ 50 km apart), but also within river systems by large
treeless canyons (>100 km). Significant population genetic differentiation within some rivers
corresponded with zones of different cottonwood (riparian poplar) tree species and their
hybrids. This study illustrates the importance of considering the impacts of habitat fragmentation
at small spatial scales as well as other ecological processes to gain a better understanding
of how organisms respond to their environmental connectivity. Here, even in a
common and widespread songbird with high dispersal potential, small breaks in continuous
habitats strongly influenced the spatial patterns of genetic variation.
Description
Sherpa Romeo green journal
Keywords
Gene flow , Population genetics , Birds -- Dispersal , Black-capped chickadee , Fragmented landscapes , Southern Alberta
Citation
Adams, R. V., & Burg, T. M. (2015). Gene flow of a forest-dependent bird across a fragmented landscape. PLoS ONE, 10(11), e0140938. doi:10.1371/journal.p one.0140938