Application of Maxent Multivariate Analysis to Define Climate-Change Effects on Species Distributions and Changes

Army installation managers and planners have limited sources of scientifically reliable information that can be used to examine potential climate impacts on local flora and fauna. The present work evaluated the viability and versatility of applying statistical multivariate analysis to define the current and projected future range probability for species of interest to Army land managers. A software program called Maxent was used to perform range-extent analyses for two animal species of interest to Army land managers the Red-Cockaded Woodpecker RCW and the common musk turtle. The technology was used to determine how climate change might affect species thresholds of survival at Army installations. The software data input requirements and output capabilities are described. The analytical methodology applied to the study of both species is discussed in detail, and validation of results is addressed. The authors conclude that Maxent analyses can provide impartial, data-based results that reflect scientific consensus on related climate-change issues while avoiding emphasis on the extremes of scientifically collected data. Analysis results indicate that climate change will alter RCW habitat threshold values on some installations beyond the point where Army-managed mitigation is possible. In contrast, musk turtle habitat will increase at least until 2025.