Linking survey detection accuracy with ability to mitigate populations of mountain pine beetle

Abstract

In 2007, the mountain pine beetle impacted an estimated 10.1 million hectares of pine forest in British Columbia, Canada. Surveys to detect the location, size, and impact of infestations are conducted from field, airborne, and satellite perspectives. Importantly, the differing survey approaches characterize the infestation over dissimilar spatial scales (i.e., trees, stands, landscapes), and with varying levels of detection accuracy. In this communication, we provide background for understanding differing survey approaches, the nature of the information generated, the resultant detection accuracies that may be expected, and the link between survey accuracy and the ability to mitigate a given mountain pine beetle infestation. A detection accuracy of 100% implies that all infested trees could be mitigated; however, no survey method achieves this level of detection accuracy, and therefore some residual infestation will persist, facilitating further population expansion if other environmental factors are conducive. Based upon this understanding, we model the number of years of mitigation effort required to maintain endemic beetle population levels, as a function of the survey approach used and the expected detection accuracy. Key words: mountain pine beetle, survey, detection, remote sensing, accuracy, mitigation, insect, Landsat, QuickBird, aerial-overview survey, heli-GPS