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Fission‐Fusion Group Dynamics and Cooperative Hunting Stabilise Social Carnivore PopulationsNARA Subscribed
Theory suggests that large social groups of carnivores should be unsustainable, due to reduced foraging efficiency because of overlapping perception radii. Using Serengeti lions as a case study, we apply behaviourally based foraging models to show that fragmentation of social groups into smaller subgroups or mutual cooperation during hunting are both plausible hypothetical mechanisms capable of sustaining larger lion prides. D...
Humanity has never benefited more from the ocean as a source of food, livelihoods, and well-being, yet on a global scale this has been accompanied by trajectories of degradation and persistent inequity. Awareness of this has spurred policymakers to develop an expanding network of ocean governance instruments, catalyzed civil society pressure on the public and private sector, and motivated engagement by the general public as co...
Invasion syndromes: a systematic approach for predicting biological invasions and facilitating effective managementNARA Subscribed
Our ability to predict invasions has been hindered by the seemingly idiosyncratic context-dependency of individual invasions. However, we argue that robust and useful generalisations in invasion science can be made by considering “invasion syndromes” which we define as “a combination of pathways, alien species traits, and characteristics of the recipient ecosystem which collectively result in predictable dynamics and impacts,...
The diversification of neopasiphaeine bees during the Cenozoic (Hymenoptera: Colletidae)NARA Subscribed
The biogeography of colletid bees as a whole can be explained by several South American‐Australian trans‐Antarctic interchanges. Within Colletidae, neopasiphaeine bees form a large group that has not been adequately studied, even though they are interesting both from the biogeographical viewpoint for fitting well the austral Gondwanan track and for their associations to host plants. The present paper integrates phylogenetic, b...
The current extinction and climate change crises pressure us to predict population dynamics with ever‐greater accuracy. Although predictions rest on the well‐advanced theory of age‐structured populations, two key issues remain poorly explored. Specifically, how the age‐dependency in demographic rates and the year‐to‐year interactions between survival and fecundity affect stochastic population growth rates. We use inference, si...
A ‘dynamic’ landscape of fear: prey responses to spatiotemporal variations in predation risk across the lunar cycleNARA Subscribed
Ambiguous empirical support for ‘landscapes of fear’ in natural systems may stem from failure to consider dynamic temporal changes in predation risk. The lunar cycle dramatically alters night‐time visibility, with low luminosity increasing hunting success of African lions. We used camera‐trap data from Serengeti National Park to examine nocturnal anti‐predator behaviours of four herbivore species. Interactions between predicta...
The case for fencing remains intactNARA Subscribed
Creel et al . argue against the conservation effectiveness of fencing based on a population measure that ignores the importance of top predators to ecosystem processes. Their statistical analyses consider, first, only a subset of fenced reserves and, second, an incomplete examination of ‘costs per lion.’ Our original conclusions remain unaltered.
Conserving large carnivores: dollars and fenceNARA Subscribed
Conservationists often advocate for landscape approaches to wildlife management while others argue for physical separation between protected species and human communities, but direct empirical comparisons of these alternatives are scarce. We relate African lion population densities and population trends to contrasting management practices across 42 sites in 11 countries. Lion populations in fenced reserves are significantly cl...
Tanzania holds most of the remaining large populations of African lions ( Panthera leo ) and has extensive areas of leopard habitat ( Panthera pardus ), and both species are subjected to sizable harvests by sport hunters. As a first step toward establishing sustainable management strategies, we analyzed harvest trends for lions and leopards across Tanzania's 300,000 km 2 of hunting blocks. We summarize lion population trends i...
Conservation Genetics of Potentially Endangered Mutualisms: Reduced Levels of Genetic Variation in Specialist versus Generalist BeesNARA Subscribed
Oligolectic bees collect pollen from one or a few closely related species of plants, whereas polylectic bees visit a variety of flowers for pollen. Because of their more restricted range of host plants, it maybe expected that specialists exist in smaller, more isolated populations, with lower effective population sizes than generalists. Consequently, we hypothesized that oligolectic bees have reduced levels of genetic variatio...
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