Ruben Portas

Anthropogenic land conversion is putting increasing pressure on wildlife populations around the world. To mitigate impacts, it is necessary to develop a detailed mechanistic understanding of how animals are affected by different types of human activity. A key challenge is to disentangle the effects of static infrastructure, like roads or buildings, and the presence of humans in the landscape. To address this question, we examined if terrestrial mammals altered their movement behaviour around buildings in response to reduced human mobility during COVID‐19 lockdowns. We compiled GPS tracking data from 35 study sites across five continents, for 10 carnivore species and 13 herbivore species, totalling >1 million location records from 586 individuals. For each study, we used integrated step selection analysis to test the extent to which animals changed their avoidance of buildings as lockdown took effect, leveraging the recently released Microsoft MLBuildings dataset of global building locations. Analysis of population‐level effects revealed that, in areas with high Human Footprint Index (HFI), animals tended to show a significant reduction in their avoidance of buildings during lockdown, but not in low HFI areas. No such trend was detected during equivalent periods in years other than 2020, indicating that behavioural changes were a result of reduced human mobility during lockdowns. Overall, our findings suggest that animals living alongside humans exhibit greater plasticity when people change their behaviour, likely indicating the combined effects of environmental filtering and habituation. More generally, our study provides a critical first step towards developing evidence‐based tools for forecasting how wildlife movement behaviour may change in response to different land‐use strategies, human activities, conservation interventions or environmental perturbations.

Non-invasive fecal sampling is essential for molecular wildlife studies such as gut microbiome (GMB) research, yet field conditions often limit preservation options. To test the effects of preservation methods on the results of GMB community composition, we compared gut bacterial communities in paired fecal samples preserved in stabilization tubes and air-dried in paper bags collected from anesthetized African lions ( Panthera leo ) and spotted hyenas ( Crocuta crocuta ) in Etosha National Park, Namibia. Additional opportunistic samples from the ground around carnivore feeding sites that varied in moisture content were also analyzed. No differences in alpha or beta diversity were detected between preserved and dried samples, although bacterial beta diversity differed between preserved and opportunistic samples, supported by NMDS ordinations and PERMANOVA results. Core bacterial communities remained consistent across opportunistic sample conditions, indicating that host-associated taxa persist despite environmental exposure supporting the use of opportunistic samples for GMB studies in remote arid settings. However, consistent sampling protocols and future field-based desiccation studies remain critical for comparative analyses. These findings highlight that rapid air-drying offers a reliable, low-cost preservation option that maintains core microbiome patterns, expanding the feasibility of GMB research in remote or resource-limited field contexts where refrigeration and preservatives may be unavailable.

Vultures are avian obligate scavengers which provide important ecosystem services by efficiently removing carcasses from the landscape. Some species are now being observed feeding in coastal environments where they consume marine carcasses (i.e., whales, dolphins, seals and fish). On the African continent, only two species thus far have been reported to feed in the coastal ecosystems: the Lappet‐faced Vulture ( Torgos tracheliotos ) on the Skeleton Coast of Namibia and the Hooded Vulture ( Necrosyrtes monachus ) in southern Gambia. Here we report on the first observation of four White‐backed Vultures feeding on a Cape fur seal ( Arctocephalus pusillus ) killed by lions ( Panthera leo ). These observations carry several ecological and conservation implications and raise certain conservation concerns, including marine nutrients transfer and potential accumulation of marine environmental toxicants.

Vultures are avian obligate scavengers which provide important ecosystem services by efficiently removing carcasses from the landscape. This role has been extended by some species to the coastal environments where they consume marine carcasses (i.e. whales, dolphins, seals and fish). On the African continent, only two species were reported to feed in the coastal ecosystems: the Lappet-faced Vulture (Torgos tracheliotos) on the Skeleton Coast of Namibia and the Hooded Vulture (Necrosyrtes monachus) in southern Gambia. Here we report on the first observation of four White-backed Vultures feeding on a Cape fur seal (Arctocephalus pusillus). This has several ecological and conservation implications, including marine nutrients transfer and potential threat due to accumulation of marine environmental toxicants.

There is growing evidence from around the globe about the crucial role of predators in ecosystem functioning at many trophic levels. Due to the expansion of anthropogenic activities, these species are becoming increasingly dependent on protected areas for their persistence. As carnivores move beyond protected area boundaries, they often interfere with human interests, frequently resulting in conflict and persecution. The Greater Etosha Landscape (GEL) in north-central Namibia exemplifies global conservation challenges. The GEL comprises one of the world's most renowned protected areas, the Etosha National Park, which is surrounded by a diverse matrix of land tenures and land uses, which translate into different management approaches and predator tolerances. While large carnivore research has a long history in the Etosha landscape, changing land use and climatic conditions require a new detailed understanding of the drivers of carnivore fitness and persistence. In close partnership, the Etosha Ecological Institute, as part of the Ministry of Environment, Forestry and Tourism, and the Ongava Research Centre have developed the long-term and large-scale Greater Etosha Carnivore Programme involving national and international collaborators. This collaborative programme aims to identify, understand and quantify the drivers of carnivore distribution and abundance in the GEL. Here, we provide general information about our programme's aim and partners, and this serves as an introduction to the more in-depth presentations on specific research and conservation projects falling under its umbrella.

Cheetahs (Acinonyx jubatus) are endangered large carnivores with key roles in the ecosystem. Although many aspects of their ecology are well studied, population estimates across their range are scarce or not comparable. To carry out science-based management plans and develop long-term conservation strategies for cheetahs, population monitoring based on regular and accurate surveys using the most appropriate methodology are crucial. Here, we describe a novel method to survey the cheetah population. Our approach considers the unique spatial ecology of cheetahs, which is characterized by territorial males defending communication hubs (CHs) not adjacent to each other but separated by a surrounding matrix of low cheetah activity and non-territorial males roaming over large areas and encompassing several of these territories. This results in an uneven, but predictable distribution of cheetah males in the landscape. Our approach used movement data obtained from free-ranging cheetah males fitted with GPS collars to identify marking sites located within the CHs. These marking sites were monitored with camera traps in six study sites across Namibia. The resulting camera trapping data were analysed with spatial capture–recapture methods to provide density estimates for cheetahs in the different Namibian biomes. The methodology proposed proved to be robust and provided a high camera capture probability due to a high recapture rate, which is particularly relevant for wide-ranging species that occur at low densities. Our approach provides a valuable baseline for the management and conservation of cheetahs in Namibia and could be used across cheetah's range.

Anthropogenic land conversion is increasingly affecting wildlife populations. To mitigate impacts, we must understand how animals are affected by different types of human activity. Here, we examine if terrestrial mammals altered their movements around buildings in response to reduced human mobility during COVID-19 lockdowns. Using GPS data from 35 study sites across five continents and 23 different species, we tested whether animals changed their avoidance of buildings during lockdowns. Meta-analysis of population-level effects revealed that, in areas with high (but not low) human footprint, animals tended to show a significant reduction in their avoidance of buildings during lockdown. No such effect was detected during equivalent periods in years other than 2020, indicating that behavioural changes were caused by reduced human mobility, independent of infrastructure. Our findings suggest that animals living alongside humans exhibit greater plasticity when people change their behaviour, likely reflecting the combined effects of environmental filtering and habituation.

Bio‐logging technologies allow scientists to remotely monitor animal behaviour and the environment. In this study, we used the combination of natural abilities of African white‐backed vultures Gyps africanus and state‐of‐the‐art bio‐logging technology for detecting and locating carcasses in a vast landscape. We used data from two captive and 27 wild vultures to create a reference data set for the training of a support vector machine to distinguish between six behaviour classes based on acceleration data. Next, we combined the classified behaviour of the initial 27 and 7 additional vultures with GPS data and used the ‘Density‐Based Spatial Clustering of Applications with Noise’ algorithm to cluster all GPS data to get a position of potential feeding locations. Finally, we used the clustered data set to train a Random Forest algorithm to distinguish between clusters with and without a carcass. The behaviour classifier was trained on 14,682 samples for all behaviour classes, which were classified with a high performance (overall precision: 0.95, recall: 0.89). This enabled a ground team to examine 1900 clusters between May 2022 and March 2023 in the field, 580 linked to a carcass and 1320 without a carcass. The cluster classifier trained on this data set was able to correctly distinguish between carcass and no carcass clusters with high performance (overall precision: 0.92, recall: 0.89). Synthesis and applications. We showed that a carcass detection system using vultures, loggers and artificial intelligence (AI) can be used to monitor the mortality of numerous species in a vast landscape. This method has broad applications, such as studying the feeding ecology of vultures, detecting and monitoring of disease outbreaks, environmental poisoning or illegal killing of wildlife. Similar to vultures and carcasses, our methodological framework can be applied to other species to locate their respective food resources. It could also be applied to other types of resources like temporary water sources, roosting sites and to other behaviours such as marking to locate marking sites.