| Title: | Diverse effects of the common hippopotamus on plant communities and soil chemistry |
| Author(s): | McCauley DJ; Graham SI; Dawson TE; Power ME; Ogada M; Nyingi WD; Githaiga JM; Nyunja J; Hughey LF; Brashares JS; |
| Address: | "Department of Ecology, Evolution and Marine Biology and the Marine Science Institute, University of California, Santa Barbara, CA, 93106, USA. douglas.mccauley@ucsb.edu. Department of Biology, University of Washington, Seattle, WA, 98195, USA. Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, 94720, USA. Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA. Conservation Solutions Afrika, P.O. Box 880, Nanyuki, 10400, Kenya. National Museums of Kenya, Ichthyology Section, P.O. Box 40658-00100, Nairobi, Kenya. School of Biological Sciences, University of Nairobi, P.O. Box 30197, Nairobi, Kenya. Kenya Wildlife Service, Wetlands Program, P.O. Box 40241-00100, Nairobi, Kenya. Department of Ecology, Evolution and Marine Biology and the Marine Science Institute, University of California, Santa Barbara, CA, 93106, USA" |
| DOI: | 10.1007/s00442-018-4243-y |
| ISSN/ISBN: | 1432-1939 (Electronic) 0029-8549 (Linking) |
| Abstract: | "The ecological importance of the common hippopotamus (Hippopotamus amphibius) in aquatic ecosystems is becoming increasingly well known. These unique megaherbivores are also likely to have a formative influence on the terrestrial ecosystems in which they forage. In this study, we employed a novel exclosure design to exclude H. amphibius from experimental plots on near-river grasslands. Our three-year implementation of this experiment revealed a substantial influence of H. amphibius removal on both plant communities and soil chemistry. H. amphibius significantly reduced grassland canopy height, increased the leafiness of common grasses, reduced woody plant abundance and size, and increased the concentrations of several soil elements. Many of the soil chemistry changes that we experimentally induced by exclusion of H. amphibius were mirrored in the soil chemistry differences between naturally occurring habitats of frequent (grazing lawns) and infrequent (shrub forest) use by H. amphibius and other grazing herbivores. In contrast to existing hypotheses regarding grazing species, we found that H. amphibius had little effect on local plant species richness. Simultaneous observations of exclosures designed to remove all large herbivores revealed that H. amphibius removal had ecologically significant impacts, but that the removal of all species of large herbivores generated more pronounced impacts than the removal of H. amphibius alone. In aggregate, our results suggest that H. amphibius have myriad effects on their terrestrial habitats that likely improve the quality of forage available for other herbivores. We suggest that ongoing losses of this vulnerable megaherbivore are likely to cause significant ecological change" |
| Keywords: | Animals *Artiodactyla Ecosystem Herbivory Plants *Soil Exclosure Grazing lawn Megaherbivore Nutrient cycling Vegetation structure; |
| Notes: | "MedlineMcCauley, Douglas J Graham, Stuart I Dawson, Todd E Power, Mary E Ogada, Mordecai Nyingi, Wanja D Githaiga, John M Nyunja, Judith Hughey, Lacey F Brashares, Justin S eng Germany 2018/08/14 Oecologia. 2018 Nov; 188(3):821-835. doi: 10.1007/s00442-018-4243-y. Epub 2018 Aug 11" |
