Interplay of competition and facilitation in grazing succession by migrant Serengeti herbivores

• 成果类型: Article
• 署名作者: Anderson, T. Michael; Hepler, Staci A.; Holdo, Ricardo M.; Donaldson, Jason E.; Erhardt, Robert J.; Hopcraft, J. Grant C.; Hutchinson, Matthew C.; Huebner, Sarah E.; Morrison, Thomas A.; Muday, Jeffry; Munuo, Issack N.; Palmer, Meredith S.; Pansu, Johan; Pringle, Robert M.; Sketch, Robert; Packer, Craig
• 署名单位: Wake Forest University; Wake Forest University; University System of Georgia; University of Georgia; University of Glasgow; University of California System; University of California Merced; University of Minnesota System; University of Minnesota Twin Cities; Princeton University; Centre National de la Recherche Scientifique (CNRS); CNRS - Institute of Ecology & Environment (INEE); Universite Claude Bernard Lyon 1
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-10615
• DOI: 10.1126/science.adg0744
• 发表日期: 2024-02-16
• 页码: 782-788
• 关键词: human impacts; ecology; predation; selection; vegetation; package; regression; allometry; landscape; EVOLUTION

摘要

Competition, facilitation, and predation offer alternative explanations for successional patterns of migratory herbivores. However, these interactions are difficult to measure, leaving uncertainty about the mechanisms underlying body-size-dependent grazing-and even whether succession occurs at all. We used data from an 8-year camera-trap survey, GPS-collared herbivores, and fecal DNA metabarcoding to analyze the timing, arrival order, and interactions among migratory grazers in Serengeti National Park. Temporal grazing succession is characterized by a push-pull dynamic: Competitive grazing nudges zebra ahead of co-migrating wildebeest, whereas grass consumption by these large-bodied migrants attracts trailing, small-bodied gazelle that benefit from facilitation. Natural experiments involving intense wildfires and rainfall respectively disrupted and strengthened these effects. Our results highlight a balance between facilitative and competitive forces in co-regulating large-scale ungulate migrations.