Predicting occurrence of the American burying beetle (Nicrophorus americanus) in Nebraska's Sandhills region

A habitat suitability model was constructed for the federally endangered American burying beetle, Nicrophorus americanus, occurring in Nebraska’s Sandhills region. Land cover and soil texture variables were analyzed, along with easting as a surrogate for precipitation, using an 800 m spatial scale. Positive and zero capture data (N=476) collected between 2001 and 2010 were used to calculate the receiver operator curve (ROC) values through logistic regression. These values and Akaike’s information criterion (AIC) scores were assessed to identify variables that best fit the occurrence of American burying beetles. Our final model inputs were loamy sand and wetlands as positive predictors, and crop land cover as a negative predictor. These variables produced a 0.74 ROC value, which is within the moderate model performance range. Model validation was completed using trap data (N=100) collected in 2011. Probability percentages predicted by the model for traps with positive or zero American burying beetle captures were compared using a student’s t-test. We found the largest areas with high probabilities of occurrence are concentrated in three northern Nebraska counties. This model allows the U.S. Fish and Wildlife Service to provide scientifically-based decisions for land use recommendations and helps identify high-priority habitat for conservation. This is important because American burying beetles’ habitat preferences are largely unknown and is considered a habitat generalist. The habitat suitability model will be a dynamic tool that can be continually updated and re-evaluated with future sampling data in efforts to protect the American burying beetle populations in Nebraska.