A warmer climate has increased the spread of mountain Pine beetle. Historically, mountain pine beetle populations were limited to southern regions due to cold temperature intolerance. However, increasing winter temperatures has allowed the species to spread further north, contributing to the loss of over 1 million ha of forest in the United States and 9 million ha in Canada.Data on mountain pine beetle damage was compiled by CMP Hi5 Working Group technical team. Aerial detection surveys between 1999–2020 for Montana, Alberta, and Waterton Lakes National Park were compiled and assigned a severity score using the USDA Forest Service classification system. Severity is based on crown mortality from aerial images, with low severity being less than 10% mortality, and high severity being greater than 30% mortality.
