Canadian Forest Service Publications
Impacts of Climate Change on Range Expansion by the Mountain Pine Beetle. 2006. Carroll, A.L.; Régnière, J.; Logan, J.A.; Taylor, S.W.; Bentz, B.; Powell, J.A. Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, Victoria, BC. Mountain Pine Beetle Initiative Working Paper 2006-14. 20 p.
Available from: Pacific Forestry Centre
Catalog ID: 26601
The current latitudinal and elevational range of mountain pine beetle (MPB) is not limited by available hosts. Instead, its potential to expand north and east has been restricted by climatic conditions unfavorable for brood development. We combined a model of the impact of climatic conditions on the establishment and persistence of MPB populations with a spatially explicit, climate-driven simulation tool. Historic weather records were used to produce maps of the distribution of past climatically suitable habitats for MPB in British Columbia. Overlays of annual MPB occurrence on these maps were used to determine if the beetle has expanded its range in recent years due to changing climate. An examination of the distribution of climatically suitable habitats in 10-year increments derived from climate normals (1921-1950 to 1971-2000) clearly shows an increase in the range of benign habitats. Furthermore, an increase (at an increasing rate) in the number of infestations since 1970 in formerly climatically unsuitable habitats indicates that MPB populations have expanded into these new areas. The potential for additional range expansion by MPB under continued global warming was assessed from projections derived from the CGCM1 global circulation model and a conservative forcing scenario equivalent to a doubling of CO2 (relative to the 1980s) by approximately 2050. Predicted weather conditions were combined with the climatic suitability model to examine the distribution of benign habitats from 1981-2010 to 1941-2070 for all of Canada. The area of climatically suitable habitats is anticipated to continue to increase within the historic range of MPB. Moreover, much of the boreal forest will become climatically available to the beetle in the near future. Since jack pine is a viable host for MPB and a major component of the boreal forest, continued eastward expansion by MPB is probable.