The influence of scavenger guilds on carcass-related nutrient fluxes

<b>Abstract</b>The decomposition of carcasses can severely alter the local soil chemical composition and biochemical cycles, which highly depends on the interplay between both vertebrate and invertebrate scavengers and microbial decomposers. Different scavenger species are assumed to differently influence carcass-derived elemental fluxes. However, the impact that different scavenger guilds can have on local nutrient dynamics remains unknown. Here, we experimentally determine how different scavenger guilds influence local nutrient dynamics. We hypothesized that vertebrate scavengers, particularly wild boar (<i>Sus scrofa</i>), can take up the majority of nutrients in their bodies, resulting in the largest local elemental leakage when only invertebrates have access. We performed a field experiment in which we systematically excluded different subsets of vertebrate scavengers from decomposing carcasses, and compared elemental concentrations in soil beneath and vegetation next to the carcasses over time throughout the decomposition process. We used four exclusion treatments: excluding (1) no scavengers; (2) wild boar; (3) all mammals; and (4) all mammals and birds. We found that vertebrate scavengers limited the influence of elemental leakage from the carcasses into the soil, and hence not influencing local nutrient dynamics. When vertebrates were excluded, fluxes of several nutrients into the soil showed distinct peaks. Especially trace elements (Cu and Zn) seemed to be influenced by carcass decomposition. Our results suggest that carcass-derived nutrients are dispersed over larger areas rather than locally leak into the soil when vertebrate scavengers dominate the decomposition process.