Modelling Mountain Pine Beetle Abundance and Distribution in Novel Hosts and Changing Climate

  • Author / Creator
    Xie, Xiaoqi
  • The mountain pine beetle (Dendroctonus ponderosae, Hopkins 1902), an invasive bark beetle native to North America, has expanded its habitat from central British Columbia to Northern Alberta. This expansion poses an immediate threat to jack pine forests, which extend from Alberta to Nova Scotia. Past studies have revealed the beetle’s successful attacks on jack pines, and laboratory research has indicated that jack pine possesses limited defensive capabilities. These findings have heightened concerns about the potential range expansion of the beetle and underscore the need to quantify potential risks in jack pine forests. Additionally, lodgepole pine, the primary host of the beetle, has been substantially infested in Alberta. The impacts of climate change could increase the frequency and severity of these infestations in lodgepole pine forests, leading to significant economic and ecological losses. Therefore, studying the effects of climate change on beetle’s dynamics is imperative.
    In this thesis, we addressed concerns regarding the susceptibility of jack pine and the potential impacts of climate-related covariates on infestations in lodgepole pine forests under climate change. In Chapter 2, we discussed the environmental and ecological covariates significant for mountain pine beetle population dynamics in Alberta and selected a suitable model using these covariates to examine these biological questions. Our results indicated that the hierarchical model outperforms others. Employing this model, Chapter 3 discussed the risk of infestations in jack pine and compared the reproduction rate of jack pine to that of lodgepole pine. The model revealed a low likelihood of infestations in jack pine forests, accompanied by a weaker reproduction rate. Chapter 4 introduced the influence of climate-related covariates on the presence and abundance of infestations in lodgepole pine forests under climate change. We analyzed the potential influence of each covariate individually and their combined impact on the overall trends in the presence and abundance of infestations. The results underscored the significant role of degree days and overwinter survival rate, indicating an increase in the frequency and severity of infestations.

  • Subjects / Keywords
  • Graduation date
    Spring 2024
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.