HISTORIC DISTRIBUTION AND EXPANSION OF THE MOUNTAIN PINE BEETLE IN ROCKY MOUNTAIN NATIONAL PARK AND ADJACENT REGIONS

The mountain pine beetle (MPB) or Dendroctonus ponderosae is a native insect common to western United States that destroys conifer species that are common to the Rocky Mountain region as well as much of the western US. The life cycle of the beetle includes life stages in which the eggs are laid underneath the bark and after hatching, the larva feed on the pine trees. This results in the girdling and ultimately the death of the tree. While these beetles have always existed in this region, it is believed that climate change has enabled the MPB to extend its range to the higher reaches of the Rockies, including the Rocky Mountain National Park (RMNP). Due to excessive cost and rapid progression of the MPB it is very difficult to employ an effective method to retard the damage. The factors contributing to the expansion of the MPB within the park has raised the issue of how much of the RMNP will ultimately be affected. Prior research has defined the susceptible conifer species and classification for those infected and damaged. Through the use of remotely sensed imagery it is possible to identify the areas of MPB damage in Larimer, Grand, and Boulder counties in Colorado where the park is located.

Using satellite imagery and GIS analysis, the study area has been evaluated to determine the spatial extent of the MPB damage in 5 year increments from 1985 through 2010. The use of temporal analysis enabled us to evaluate the spatial progression of the MPB within the RMNP and classify into risk groups. In addition to correlating damaged areas sequentially over the past 25 years, this research investigates the relationship between beetle infestation and terrain, specifically comparing slope and aspect characteristics within the extent of the existing damage. Along with identifying damaged areas within the park, an equally sized area adjacent to the park will be examined to determine if the amount of MPB damage outside the park is equivalent. Ultimately, this research provides a better understanding of the extent, progression and also underlying contributory terrain factors that are responsible for MPB damage in the Rocky Mountain National Park.