Anthropogenic risk increases night-time activities and associations in African elephants (Loxodonta africana) in the Ruaha-Rungwa ecosystem, Tanzania

Elephants face diverse threats from human activities and use temporal and social strategies to reduce human-induced mortality risk. We used data from camera trap surveys in 2018–2019 (n= 1625 independent detection events from 11,751 sampling days) to investigate elephant responses to anthropogenic risk in the Ruaha-Rungwa ecosystem, Tanzania. The study was conducted in one low- risk and three high- risk sites using 26–40 paired camera trap stations per site. Risk influenced the active pe-riods, use of roads and water sources, social associations and behaviour of elephants. Elephants demonstrated significantly more night-time and reduced daytime activ-ity in the high- risk sites relative to the low- risk site. This higher night-time activity in the high- risk sites was observed for both males and females, though it was more pronounced for cow–calf groups than lone males. Foraging events and use of water sources were more frequent at night in the high- risk sites. Elephants used roads as movement routes in the low- risk site but avoided roads in the high- risk sites. Males were significantly more likely to associate with other males and cow–calf groups in the high- risk sites. Fewer occurrences of relaxed behaviours were observed in the high- risk sites compared to the low- risk site. We discuss the potential implications of our findings for elephant survival and reproduction.Output Status: Forthcoming/Available Onlin

How Does Africa's Most Hunted Bat Vary Across the Continent? Population Traits of the Straw-Coloured Fruit Bat (Eidolon helvum) and Its Interactions with Humans

The straw-coloured fruit bat, Eidolon helvum, is a common and conspicuous migratory species, with an extensive distribution across sub-Saharan Africa, yet hunting and habitat loss are thought to be resulting in decline in some areas. Eidolon helvum is also a known reservoir for potentially zoonotic viruses. Despite E. helvum's importance, ecological and behavioural traits are poorly described for this species. Here we present extensive data on the distribution, migration patterns, roost size, age and sex composition of 29 E. helvum roosts from nine countries across tropical Africa, including roosts not previously described in the literature. Roost age and sex composition were dependent on timing of sampling relative to the annual birth pulse. Rather than a single 'breeding season' as is frequently reported for this species, regional asynchrony of reproductive timing was observed across study sites (with birth pulses variably starting in March, April, September, November or December). Considered together with its genetic panmixia, we conclude that the species has a fluid, fission-fusion social structure, resulting in different roost 'types' at different times of the year relative to seasonal reproduction. Bat-human interactions also varied across the species' geographical range. In the absence of significant hunting, large urban colonies were generally tolerated, yet in regions with high hunting pressure, bats tended to roost in remote or protected sites. The extensive quantitative and qualitative data presented in this manuscript are also valuable for a wide range of studies and provide an historical snapshot as its populations become increasingly threatened.Funding for this study was provided by the Cambridge Infectious Diseases Consortium (grant VT0105 — AJP, DTSH, KSB), The Charles Slater Trust (AJP), Zebra Foundation for Veterinary Zoological Education (AJP), Isaac Newton Trust (AJP), the Wellcome Trust (DTSH, KSB), a David H. Smith postdoctoral fellowship (DTSH), the RAPIDD program of the Science and Technology Directorate, Department of Home - land Security, Fogarty International Center, National Institutes of Health (DTSH, JLNW), The Albo rada Trust (JLNW), a European Union FP7 project ANTIGONE (Antici pat ing Glob - al Onset of Novel Epidemics 278976) (ACB, JLNW, AAC) and a Royal Society Wolfson Research Merit Award (AAC).Peer Reviewe