No life without death: Scavengers enhance nutrient cycles via carcass decomposition

Summary

Increased soil acidification has resulted in imbalanced availability of nutrients (chemical elements) in many ecosystems, including Dutch protected areas. I investigated whether large animals play a crucial role in restoring elemental cycles by accumulating elements in their bodies during their lifespan, that eventually will be recycled via carrion decomposition. First, I found that animals contain high concentrations of scarce elements in their bodies but that this can considerably vary. Second, the local scavenger community plays a key role in determining the carcass decomposition speed and hence how carcass-stored elements will be recycled. Especially wild boar (Sus scrofa) can speed up the decomposition speed. Last, when vertebrate scavengers dominate the decomposition process, they prevent the leakage of scarce elements into the soil. Overall, I concluded that the natural circle of life of larger-sized animals, and the presence of vertebrate scavengers, is crucial for the redistribution of scarce nutrients over the landscape.