Beyond Park Boundaries: Pastoral Rangelands as Functional Habitat for Migratory Herbivores in the Serengeti Ecosystem

Abstract

Communal rangelands outside core protected areas are vital for biodiversity conservation and pastoral livelihoods. The Serengeti–Mara Ecosystem (SME) in Tanzania and Kenya includes both protected areas and communal areas that border the parks. The communal areas provide seasonal habitats for migratory and resident wildlife while also supporting livestock grazing by Masai pastoralists. This study assessed the distribution and seasonal use of communal rangelands in Loliondo by wildlife and livestock to facilitate sustainable rangeland management and land-use planning. Fourteen 4 km transects were established across three sites: the Loliondo Plains (365 km²), Sukenya Plains (71 km²), and Enashiva Nature Reserve (40 km²), and surveys were conducted during wet and dry seasons from February 2023 to October 2025. We found that wildlife abundance was highest in the Loliondo Plains, particularly during the wet season. Population estimates for wildebeest, zebra, and Thomson's gazelle ranged from 50,000 to 100,000 animals, with calves indicating the area's importance as a key calving area. Livestock densities were greatest in the Sukenya Plains, especially during the dry season. Loliondo Plains and Enashiva Nature Reserve supported very high wet-season wildlife and juvenile densities (100–300 individuals/km² for each species), much higher than those in the Sukenya Plains, indicating their importance as breeding and seasonal grazing habitats. Rainfall variability strongly influenced the spatial and seasonal distribution of both wildlife and livestock; in the wet year 2024, the species remained on the plains for much longer. These findings highlight the ecological significance of communal rangelands outside protected areas in sustaining migratory connectivity and pastoral livelihoods. We recommend participatory land-use planning to balance livestock production, wildlife conservation, and sustainable resource use in the eastern SME.