Detailed Record



Impacts of large herbivores on terrestrial ecosystems


Abstract Large herbivores play unique ecological roles and are disproportionately imperiled by human activity. As many wild populations dwindle towards extinction, and as interest grows in restoring lost biodiversity, research on large herbivores and their ecological impacts has intensified. Yet, results are often conflicting or contingent on local conditions, and new findings have challenged conventional wisdom, making it hard to discern general principles. Here, we review what is known about the ecosystem impacts of large herbivores globally, identify key uncertainties, and suggest priorities to guide research. Many findings are generalizable across ecosystems: large herbivores consistently exert top-down control of plant demography, species composition, and biomass, thereby suppressing fires and the abundance of smaller animals. Other general patterns do not have clearly defined impacts: large herbivores respond to predation risk but the strength of trophic cascades is variable; large herbivores move vast quantities of seeds and nutrients but with poorly understood effects on vegetation and biogeochemistry. Questions of the greatest relevance for conservation and management are among the least certain, including effects on carbon storage and other ecosystem functions and the ability to predict outcomes of extinctions and reintroductions. A unifying theme is the role of body size in regulating ecological impact. Small herbivores cannot fully substitute for large ones, and large-herbivore species are not functionally redundant - losing any, especially the largest, will alter net impact, helping to explain why livestock are poor surrogates for wild species. We advocate leveraging a broad spectrum of techniques to mechanistically explain how large-herbivore traits and environmental context interactively govern the ecological impacts of these animals.
Authors Robert M. Pringle ORCID , Joel O. Abraham ORCID , T. Michael Anderson ORCID , Tyler C. Coverdale ORCID , Andrew B. Davies ORCID , Christopher L. Dutton ORCID , Angela Gaylard ORCID , Jacob R. Goheen University of WyomingORCID , Ricardo M. Holdø ORCID , Matthew C. Hutchinson ORCID , Duncan M. Kimuyu ORCID , Ryan A. Long ORCID , Amanda L. Subalusky ORCID , Michiel P. Veldhuis ORCID
Journal Info Elsevier BV | Current Biology , vol: 33 , iss: 11 , pages: R584 - R610
Publication Date 6/1/2023
ISSN 0960-9822
TypeKeyword Image article
Open Access bronze Bronze Access
DOI https://doi.org/10.1016/j.cub.2023.04.024
KeywordsKeyword Image Ecosystem Resilience (Score: 0.52796) , Ecosystem (Score: 0.50953) , Habitat Selection (Score: 0.508224)