I use genetic and genomic tools to understand how natural and human-altered landscapes affect connectivity among populations. I explore these ideas using a range of systems.
Metapopulation genomic connectivity across space and time in Arvicola amphibius
Metapopulations are naturally structured populations, and their dynamics can provide insight into processes occurring in landscapes fragmented by human activities. I apply genomic tools to better understand metapopulation dynamics across space and time in the water vole (Arvicola amphibius), in northwestern Scotland. I will use SNPs to analyze spatial genetic structure and dispersal within this metapopulation. I am conducting this study with my current postdoc advisor Chris Sutherland (University of Massachusetts) and Xavier Lambin (University of Aberdeen).
Restoration of connectivity in Alosa pseudoharengus
In the St. Croix River system along the Maine-New Brunswick (Canada) border, dam construction over the past century or more has created multiple barriers to movement for populations of river herring (Alosa pseudoharengus), also known as alewife. Although anadromous river herring have been blocked from moving upstream to spawn, some river herring have succeeded in living out their entire life cycle above these dams, leading to several interesting questions about their ecological role and origin. Working with Lisa Komoroske, Adrian Jordaan, and Matt Devine (University of Massachusetts) and officials from the Passamaquoddy Tribe, I am using genomic tools to understand the spatial genetic structure of this system both prior to and following recent efforts to restore connectivity above dams using fish ladders.
Landscape genomics of Sabatia angularis in fragmented serpentine barrens grasslands
In collaboration with my former postdoc advisor, Rachel Spigler (Temple University), I use a landscape genomic approach to determine the effects of human land use on connectivity in populations of S. angularis. Specifically, I am interested in the relative impacts of agriculture, forest, and urbanization on connectivity among populations of S. angularis in vulnerable serpentine barren habitats in southeastern Pennsylvania. I am also looking for any potential variation in adaptation to the harsh serpentine soils. In a related study, I investigated contemporary patterns of phenotypic selection at local scales with Rachel Spigler and Steve Franks (Fordham University), finding a relationship between pollination intensity and strength of selection on floral and plant traits among populations of S. angularis.
Comparative landscape genetics of Rhyacotriton species
Comparative landscape genetic studies can tell us whether relationships between landscape features and patterns of spatial genetic structure differ among populations, species, habitat types, and regions. I use a comparative landscape genetic approach to determine the role of habitat features in shaping connectivity among populations of within two torrent salamander species, Rhyacotriton kezeri and R. variegatus in the Pacific Northwest. These species are vulnerable to effects of timber harvest, which is the dominant land-use activity in the region. This work is in collaboration with my Ph.D. advisor, Andrew Storfer (Washington State University), as well as Dede Olson (USFS) and Lacey Knowles (University of Michigan).