Date of this Version
Hoback, W.W., Conley, A "Overwintering Biology and Tests of Trap and Relocate as a Conservation Measure for Burying Beetles" (2014) Nebraska Department of Roads Research Report
Burying beetles are carrion beetles and utilize dead animal carcasses for feeding and reproductive efforts. They assist with decomposition, prevent the spread of disease, and reduce the number of pest species. The largest species of carrion beetle, the American burying beetle, is a federally endangered insect and its distribution has been reduced by 90%. The conservation of this species is important in maintaining a healthy ecosystem. Overwintering biology and trap and relocation were studied to determine how this beetle survives freezing temperatures and to find whether trap and relocation could be a suitable conservation management measure.
Trap and relocation is a technique often used to relocate organisms from an area where human and animal habitats overlap. In this study, we test the efficacy of a trap- relocate technique with a surrogate species of burying beetle, Nicrophorus marginatus, to determine the implications of this technique on the conservation management of the federally endangered American burying beetle, Nicrophorus americanus. Baited pitfall traps were used for capture, and the comparison of percent recaptures at different trap sites (control, source, and destination) was used to determine the effects of relocating
beetles. The results showed that percent recaptures were lower for the beetles relocated to the new location; however, there was no statistical difference between trap sites. Trap and relocation, in circumstances where there is substantial threat to the American burying beetle’s habitat, should be considered for conserving this species.
Insects are poikilotherms and have evolved strategies to survive freezing temperatures through changes in behavior and physiology. Overwintering insects either utilize a freeze tolerant or freeze avoidant strategy. Freeze avoidant insects cannot withstand their cellular fluids freezing solid, while freeze tolerant insects can survive this. Burying beetles from their northern range in Nebraska were put in a simulated, natural environment to determine whether they are freeze avoidant or freeze tolerant. The results showed that there was a strong relationship between beetle depth and temperature.
Beetles from the northern range buried at or below the frost line to survive freezing temperatures. This could have further implications in the conservation of the American burying beetle if there are differences between the overwintering behavior of northern and southern range beetles.