A model of Nicrophorus species occurrence in the Nebraska Loess Canyons and effects of different grasses on burial behavior

Burying beetles, Nicrophorus sp. depend on vertebrate carcasses on which they use to rear their offspring. Many Nicrophorus species have declined including the endangered American burying beetle (ABB), Nicrophorus americanus. Reasons for decline include habitat fragmentation, changing carrion base, and the use of pesticides. Extensive surveys since the federally listing of the ABB have contributed to the knowledge of its population and range; however, much remains to be discovered about its habitat affinities. The objectives of my study were to assess the impacts of different grass species on the carcass burial behavior of Nicrophorus sp., and to validate a habitat suitability model for the occurrence of the ABB in the Loess Canyons of south-central Nebraska.;In the laboratory, the effects of sod-forming grass and bunch grass on the carcass burial behavior of N. marginatus were examined. Between 2009 and 2011, 54 trials were conducted using bare soil, smooth brome grass, needle-and-thread grass, and little bluestem grass. Burying beetles moved the carcasses in the smooth brome grass conditions more frequently than in other conditions. Although beetles buried fewer carcasses and moved carcasses more frequently in smooth brome grass, statistical analyses failed to identify significance between burial behavior and grass species.;With the ABB eliminated from a large portion of its historic range, an understanding of its habitat associations will assist in management efforts. I used ABB survey data collected between 2001 and 2011 with 377 sample locations in eight south-central Nebraska counties in combination with land-cover information to develop and validate a habitat model predicting the occurrence of ABB in the Loess Canyon region of Nebraska. Using 2011 survey data, t-test results indicate significant accuracy to predict suitable habitat for the occurrence of the ABB in the Loess Canyons. In addition, my results found a significant decline in ABB occurrence with the presence of agriculture. These results demonstrate the successful use of habitat modeling to predict ABB occurrence in the Loess Canyons of Nebraska.