[Pre-print] Spatial and temporal assessments of genetic structure in an endangered Garry oak ecosystem on Vancouver Island
Date
2018-01-26Author
Catherall, Erin E.
Janes, Jasmine K.
Josefsson, Caroline A.
Gorrell, Jamieson C.
Metadata
Show full item recordAbstract
Garry oak (Quercus garryana Dougl. ex Hook.) is a deciduous tree whose
ecosystem is listed “at-risk” throughout its range in British Columbia (B.C.), Canada,
under the Canadian Species at Risk Act (SARA). Garry oak ecosystems host the most
diverse flora for coastal B.C. yet they account for less than 0.3% of the province’s landbase.
Due to the loss and degradation of Garry oak habitat, many associated plant and
animal species that rely on these sensitive ecosystems are endangered. Microsatellite
markers were used to investigate temporal changes in fine-scale population genetic
structure of 121 Garry oak trees from the Nanaimo region (Vancouver Island, B.C.) using
diameter at breast height as a proxy for age. Overall, allelic diversity was moderate,
ranging from 3.0 to 7.5 alleles per locus with an average of 4.4 (± 0.4 SE) across all loci.
Global FST of 0.06 and 0.09 suggests significant departures from Hardy-Weinberg
equilibrium among all populations and age-classified subpopulations, respectively. We
found no evidence for change in genetic diversity across generations. Our results indicate
low levels of differentiation within populations and high levels of gene flow among
populations, suggesting an adaptive potential for Garry oaks in response to future climate
change events.
Identifier (Other)
DOI: 10.1139/cjb-2017-0130DOI: 10.25316/IR-409