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Diminishing wild space and population fragmentation are key drivers of large carnivore declines worldwide. The persistence of large carnivores in fragmented landscapes often depends on the ability of individuals to move between separated subpopulations for genetic exchange and recovery from stochastic events. Where separated by anthropogenic landscapes, subpopulations' connectivity hinges on the area's socio-ecological conditions for coexistence and dispersing individuals' behavioral choices. Using GPS-collars and resource- and step-selection functions, we explored African lion (Panthera leo) habitat selection and movement patterns to better understand lions' behavioral adjustments in a landscape shared with pastoralists. We conducted our study in the Ngorongoro Conservation Area (NCA), Tanzania, a multiuse rangeland, that connects the small, high density lion subpopulation of the Ngorongoro Crater with the extensive Serengeti lion population. Landscape use by pastoralists and their livestock in the NCA varies seasonally, driven by the availability of pasture, water, and disease avoidance. The most important factor for lion habitat selection was the amount of vegetation cover, but its importance varied with the distance to human settlements, season and time of day. Although we noted high levels of individual variation in tolerance for humans, in general lions avoided humans on the landscape and used more cover when closer to humans. Females showed more consistent avoidance of humans and stronger use of cover when near humans than did males. Connectivity of lion subpopulations does not appear to be blocked by sparse pastoralist settlements, and nomadic males, key to subpopulation connectivity, significantly avoided humans during the day, suggesting a behavioral strategy for conflict mitigation. These results are consistent with lions balancing risk from humans with exploitation of livestock by altering their behaviors to reduce potential conflict. Our study lends some optimism for the adaptive capacity of lions to promote coexistence with humans in shared landscapes., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Jansson et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

In East Africa, community-based conservation models (CBCMs) have been established to support the conservation of wildlife in fragmented landscapes like the Tarangire Ecosystem, Tanzania. To assess how different management approaches maintained large herbivore populations, we conducted line distance surveys and estimated seasonal densities of elephant, giraffe, zebra, and wildebeest in six management units, including three CBCMs, two national parks (positive controls), and one area with little conservation interventions (negative control). Using a Monte-Carlo approach to propagate uncertainties from the density estimates and trend analysis, we analyzed the resulting time series (2011-2019). Densities of the target species were consistently low in the site with little conservation interventions. In contrast, densities of zebra and wildebeest in CBCMs were similar to national parks, providing evidence that CBCMs contributed to the stabilization of these migratory populations in the central part of the ecosystem. CBCMs also supported giraffe and elephant densities similar to those found in national parks. In contrast, the functional connectivity of Lake Manyara National Park has not been augmented by CBCMs. Our analysis suggests that CBCMs can effectively conserve large herbivores, and that maintaining connectivity through CBCMs should be prioritized., (© 2024. The Author(s).)

Efforts to determine whether bottom-up or top-down processes regulate populations have been hampered by difficulties in accurately estimating the population's carrying capacity and in directly measuring food intake rate, the impacts of interspecific competition and exposure to natural enemies. We report on 40 years of data on the lion population in Ngorongoro Crater, Tanzania, which showed strong evidence of density-dependent regulation at 100-120 individuals but has remained below 60 individuals for the past decade despite consistently high prey abundance. The lions enjoy a higher per capita food-intake rate and higher cub recruitment at low population density, and interspecific competition has not increased in recent years. These animals have suffered from a number of severe disease outbreaks over the past 40 years, but, whereas the population recovered exponentially from a severe epizootic in 1963, three outbreaks between 1994 and 2001 have occurred in such rapid succession that the population has been unable to return to the carrying capacity. The Crater population may have become unusually vulnerable to infectious disease in recent years owing to its close proximity to a growing human population and a history of close inbreeding. The Crater lions may therefore provide important insights into the future of many endangered populations.