Burying Beetle (Coleoptera: Silphidae: Nicrophorus Fabricius) Brooding Improves Soil Fertility

Abstract

Burying beetles (Coleoptera: Silphidae) utilize the nutrients in vertebrate carrion to reproduce. The beetles utilize the bodies of rodents and birds as a reproductive resource by burying and preparing them with secretions. Although the importance of carrion to forest and savanna soil fertility has been documented, the benefit of burying beetle brooding behavior on soil nutrients has not. Native prairie soils are among the most fertile in the world, resulting in widespread agricultural conversion. Fire suppression, allowing the spread of eastern redcedar (Juniperus virginiana L., Pinales: Cupressaceae), intense grazing, and the introduction of non-native vegetation has reduced numbers of burying beetles and potentially impacted nutrient cycling by these species. A laboratory experiment was conducted using the burying beetle Nicrophorus marginatus F. to test the influence of carcasses, beetles, and their brood on soil nutrients. Soil was placed in a 4.3-L container and treated with rat carcasses, eastern redcedar needles, and pairs of adult burying beetles. Burial success, number and weight of larvae produced, and changes to soil nutrients were recorded. Rat carcasses buried manually increased soil pH, soluble salts, and available nitrate, phosphorus, and potassium content. Beetles and their larvae increased soil nutrients far more than the manually buried rat carcasses alone. Cedar needles did not affect adult survival, brood number, or soil nutrients, although larval dry weights were significantly less in soils with cedar needles. Burying beetles and their brood increase key nutrients for plant health in native soils and are not affected by eastern redcedar needles.