Increasing Anthropogenic Disturbance Restricts Wildebeest Movement Across East African Grazing Systems

Frontiers in Ecology and Evolution

Ramiro D. Crego¹  Lacey F. Hughey¹  Peter Leimgruber¹  Christen H. Fleming²  Thomas A. Morrison³  J. Grant C. Hopcraft³  Joseph O. Ogutu⁴  Randall B. Boone⁵  Jared A. Stabach⁵  Robin S. Reid⁵  Jeffrey S. Worden⁶ 

[1] Conservation Ecology Center, Smithsonian National Zoo and Conservation Biology Institute, Front Royal, VA, United States;Department of Biology, University of Maryland, College Park, College Park, MD, United States;Institute of Biodiversity, Animal Health, and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom;Institute of Crop Science, Biostatistics Unit, University of Hohenheim, Stuttgart, Germany;Natural Resource Ecology Laboratory, Department of Ecosystem Science and Sustainability, Colorado State University, Fort Collins, CO, United States;World Wide Fund for Nature, Nairobi, Kenya;

关键词: wildebeest (Connochaetes taurinus);    anthropogenic disturbance;    NDVI;    ctmm;    ecosystem resilience;    habitat loss and fragmentation;   

DOI  :  10.3389/fevo.2022.846171

来源: DOAJ

【 摘 要 】

The ability to move is essential for animals to find mates, escape predation, and meet energy and water demands. This is especially important across grazing systems where vegetation productivity can vary drastically between seasons or years. With grasslands undergoing significant changes due to climate change and anthropogenic development, there is an urgent need to determine the relative impacts of these pressures on the movement capacity of native herbivores. To measure these impacts, we fitted 36 white-bearded wildebeest (Connochaetes taurinus) with GPS collars across three study areas in southern Kenya (Amboseli Basin, Athi-Kaputiei Plains, and Mara) to test the relationship between movement (e.g., directional persistence, speed, home range crossing time) and gradients of vegetation productivity (i.e., NDVI) and anthropogenic disturbance. As expected, wildebeest moved the most (21.0 km day–1; CI: 18.7–23.3) across areas where movement was facilitated by low human footprint and necessitated by low vegetation productivity (Amboseli Basin). However, in areas with moderate vegetation productivity (Athi-Kaputiei Plains), wildebeest moved the least (13.3 km day–1; CI: 11.0–15.5). This deviation from expectations was largely explained by impediments to movement associated with a large human footprint. Notably, the movements of wildebeest in this area were also less directed than the other study populations, suggesting that anthropogenic disturbance (i.e., roads, fences, and the expansion of settlements) impacts the ability of wildebeest to move and access available resources. In areas with high vegetation productivity and moderate human footprint (Mara), we observed intermediate levels of daily movement (14.2 km day–1; CI: 12.3–16.1). Wildebeest across each of the study systems used grassland habitats outside of protected areas extensively, highlighting the importance of unprotected landscapes for conserving mobile species. These results provide unique insights into the interactive effects of climate and anthropogenic development on the movements of a dominant herbivore in East Africa and present a cautionary tale for the development of grazing ecosystems elsewhere.

【 授权许可】

Unknown