The endangered American burying beetle (ABB), Nicrophorus americanus Olivier (Coleoptera: Silphidae), once occurred across two-thirds of North America but now occupies < 10% of its historic range. Reasons for the decline have not been determined but are generally associated with changing land use and vertebrate communities, although competition with other carrion beetles has also been suggested. We conducted extensive field surveys to characterize the ABB population and silphid community at Camp Gruber Training Base near Braggs, OK. Bi-weekly sampling was conducted from 2016 to 2019. A minimum of 15 baited above ground traps were used during each period with a minimum of two days of sampling in three different habitat categories. An intensive five-day sample period with mark and release sampling to estimate the yearly ABB population was also conducted using 20 trap locations. The estimated population on the 133 km2 Camp Gruber ranged from 1,136 to 4,657 ABB with activity occurring from April until October. ABB occurred in all sampled habitats but were more frequently captured in grasslands and savannas than forested areas. Despite a longer activity period than ABB in northern regions, only one peak of newly emerged ABB was observed in July, suggesting a single brood each year. Camp Gruber supports one of the highest remaining concentrations of ABB and routine training activities do not appear to cause substantial effects on this population.
