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Understanding the mechanisms facilitating coexistence within species assemblages is a key consideration for conservation as intact assemblages are necessary for maintaining full ecosystem function. The African large predator guild represents one of the few remaining functionally intact large predator assemblages on Earth, and as such, represents a unique study system to understand competitive interactions. Yet, relatively little is known of the coexistence mechanisms between some of its intermediately sized members, particularly leopards (Panthera pardus). Here, we use overlapping spatio-temporal activity and GPS data on lions (Panthera leo), leopards, African wild dogs (Lycaon pictus) and cheetahs (Acinonyx jubatus) to examine spatial interactions and temporal partitioning between leopards and other guild members in northern Botswana. We found that at the population level, male leopard space use and activity patterns were largely unaffected by intraguild competitors. Leopards showed minimal movement coherence with competitors (avoidance or attraction) when moving through areas of home ranges shared with intraguild species. Moreover, we found evidence to support the hypothesis that guild species' activity patterns are primarily driven by light availability rather than predator avoidance. Our results suggest predator avoidance has a limited impact on broad-scale leopard spatio-temporal niches, with aspects of the leopards' ecology and life history likely facilitating its ability to thrive in close proximity to competitors. Considered alongside other studies, our results suggest that landscape-level approaches to conservation may be suitable for aiding leopard conservation.

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Although leopards are the most widespread of all the big cats and are known for their adaptability, they are elusive and little is known in detail about their movement and hunting energetics. We used high-resolution GPS/IMU (inertial measurement unit) collars to record position, activity and the first high-speed movement data on four male leopards in the Okavango Delta, an area with high habitat diversity and habitat fragmentation. Leopards in this study were generally active and conducted more runs during the night, with peaks in activity and number of runs in the morning and evening twilight. Runs were generally short (less than 100 m) and relatively slow (maximum speed 5.3 m s −1 , mean of individual medians) compared to other large predators. Average daily travel distance was 11 km and maximum daily travel distance was 29 km. No direct correlation was found between average daily temperature and travel distance or between season and travel distance. Total daily energy requirements based on locomotor cost and basal metabolic rate varied little between individuals and over time. This study provides novel insights into movement patterns and athletic performance of leopards through quantitative high-resolution measurement of the locomotor, energetic, spatial and temporal movement characteristics. The results are unbiased by methodological and observational limitations characteristic of previous studies and demonstrate the utility of applying new technologies to field studies of elusive nocturnal species.

Understanding the degree to which animals are shifting their phenology to track optimal conditions as the climate changes is essential to predicting ecological responses to global change. Species at low latitudes or high trophic levels are theoretically expected to exhibit weaker phenological responses than other species, but limited research on tropical systems or on top predators impedes insight into the contexts in which these predictions are upheld. Moreover, a lack of phenological studies on top predators limits understanding of how climate change impacts propagate through entire ecosystems. Using a 30-y dataset on endangered African wild dogs ( Lycaon pictus ), we examined changes in reproductive phenology and temperatures during birthing and denning over time, as well as potential fitness consequences of these changes. We hypothesized that their phenology would shift to track a stable thermal range over time. Data from 60 packs and 141 unique pack-years revealed that wild dogs have delayed parturition by 7 days per decade on average in response to long-term warming. This shift has led to temperatures on birthing dates remaining relatively stable but, contrary to expectation, has led to increased temperatures during denning periods. Increased denning temperatures were associated with reduced reproductive success, suggesting that a continued phenological shift in the species may become maladaptive. Such results indicate that climate-driven shifts could be more widespread in upper trophic levels than previously appreciated, and they extend theoretical understanding of the species traits and environmental contexts in which large phenological shifts can be expected to occur as the climate changes.

The use of animal‐borne devices in wildlife studies is increasing due to the miniaturization of sensors and reductions in component costs. Retrieval of animal‐borne devices is often advantageous for several reasons, including data retrieval and animal welfare considerations; however, commercially available drop‐off units are often prohibitively expensive and/or unreliable. Here, we present ‘OpenDropOff’, an open‐source, low‐cost electronic drop‐off unit for remotely detaching animal‐borne sensors from individuals. OpenDropOff devices function by using heat, produced by running an electrical current through resistance wire (nichrome), to melt nylon (e.g. fishing) line, detaching sensors from animals at or after a pre‐determined time. OpenDropOff can be constructed using commercially available components (costing < USD $15 in total; approximately 10% or less of many commercially available drop‐off units) and can be customized to fit project‐ and species‐specific needs. Fourteen OpenDropOff devices have been field deployed on koalas (Phascolarctos cinereus) (n = 11), swamp wallaby (Wallabia bicolor) (n = 1), Australian brush turkey (Alectura lathami) (n = 1) and Australian white ibis (Threskiornis molucca) (n = 1), with the only detachment failure occurring after a device was damaged during the koala’s unrelated death. OpenDropOff devices provide a wider range of researchers with a reliable, cost‐effective tool for detaching animal‐borne sensors. Their use could allow researchers to more efficiently allocate project resources, and their flexibility provides an opportunity to mitigate animal welfare concerns surrounding the use of animal‐borne devices.

Encounters between individuals can have implications for a range of processes, including disease transmission, information transfer and competition. For large carnivores, difficulties in directly observing individuals and historical hardware limitations of GPS collars mean that relatively little is known of the spatio‐temporal factors contributing to encounters. The African large predator guild represents one of the few remaining functionally intact guilds of large carnivores on the globe and so represents a unique study system for understanding competitor interactions. We explored the drivers of male leopard (Panthera pardus) encounters with lions (Panthera leo), African wild dogs (Lycaon pictus) and cheetahs (Acinonyx jubatus) in the context of habitat characteristics and temporal activity overlaps. Using high‐resolution (five minute GPS fixes) data from 48 large African carnivores from 2012 to 2018, we quantified encounter occurrences between male leopards and other guild species and related these to habitat type (open vs closed), activity overlaps and moonlight levels. Leopards met wild dogs 4.56 ± 1.15 (standard error), lions 3.11 ± 0.56 and cheetahs 2.27 ± 0.73 times per month. All species instigated encounters, but leopard instigated encounters with dominant competitors appeared to reflect imperfect information on risk, primarily occurring within habitats with limited visibility. Moreover, encounters peaked during periods of high temporal overlap, suggesting that, although previous research indicates temporal activity patterns may not be driven by predator avoidance, temporal overlap has implications for competitor dynamics. Our results show how habitat characteristics and niche overlaps contribute to encounters between competitors and provide an example of how niche shifts within competitor assemblages can impact competition between species.