Open AccessModelling landscape genetic connectivity of the mountain pine beetle in western Canada
Author(s) -
Julian Wittische,
Jasmine K. Janes,
Patrick M. A. James
Publication year - 2019
Publication title -
canadian journal of forest research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.677
H-Index - 121
eISSN - 1208-6037
pISSN - 0045-5067
DOI - 10.1139/cjfr-2018-0417
Subject(s) - mountain pine beetle , biological dispersal , resistance (ecology) , ecology , geography , population , climate change , landscape connectivity , dendroctonus , environmental science , physical geography , biology , bark beetle , demography , sociology , bark (sound)
The current mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins, 1902) outbreak has reached more than 25 million hectares of forests in North America, affecting pine species throughout the region and substantially changing landscapes. However, landscape features that enhance or limit dispersal during the geographic expansion associated with the outbreak are poorly understood. One of the obstacles in evaluating the effects of landscape features on dispersal is the parameterization of resistance surfaces, which are often constructed based on biased expert opinion or by making assumptions in the calculation of ecological distances. In this study, we assessed the impact of four environmental variables on MPB genetic connectivity across western Canada. We optimized resistance surfaces using genetic algorithms and models of maximum likelihood population effects, based on pairwise genetic distances and ecological distances calculated using random-walk commute-time distances. Unlike other methods for the development of resistance surfaces, this approach does not make a priori assumptions about the direction or shape of the relationships between environmental features and their cost to movement. We found highest support for a composite resistance surface including elevation and climate. These results further the understanding of MPB movement during an outbreak. Additionally, we demonstrated how to use our results for management purposes.