Fence management and time since pack formation influence African wild dog escapes from protected areas in South Africa

In human-dominated and highly fragmented landscapes, keeping wildlife within reserve boundaries is vital for conservation success. In South Africa, fences are a widely employed conservation management tool for protected areas and are successful in mitigating human-wildlife conflict. However, fences are permeable, and predators are able to cross through reserve fences. African wild dogs (Lycaon pictus) often leave fenced boundaries, resulting in high capture and translocation costs. Moreover, when wild dog packs (up to 30 individuals) leave fenced reserves they enter human-dominated landscapes where they face strong persecution and livestock predation incurs high costs. The factors driving packs to leave managed reserves are poorly understood, thus, to effectively manage wild dogs in fenced systems, it is important to understand why they leave reserve boundaries. There are several hypotheses as to why wild dogs cross through reserve fences, including inter- and intra-specific competition, social behaviour, management, prey density and environmental variability. Using a long-term dataset comprising 32 resident packs across five reserves, we investigated the relative strength of these hypotheses on the probability of wild dogs exiting a fenced reserve. During the 14-year study period, we recorded 154 exit events. We found that the interaction of fence integrity and time since pack formation were the primary factors affecting the probability of a pack leaving a reserve. When fence integrity was poor, escape probability decreased with pack age likely due to the exploratory behaviour of new packs. When fence integrity was average, escape probability increased with pack age likely due to the fitness benefits of holding larger and more exclusive territories as packs age. When fence integrity was good, the probability of a pack escaping was very low (only 1% occurrence). The implications of this research suggest that the primary management consideration for reducing wild dog escapes from fenced reserves should be maintaining adequate reserve-wide fence integrity, rather than focusing on social structure or drivers of inter- and intra-specific competition

Spatial partitioning by a subordinate carnivore is mediated by conspecific overlap

There are several hypotheses that could explain territory size in mammals, including the resource dispersion hypothesis (RDH), the intruder pressure hypothesis (IPH), and the intraguild predation hypothesis (IGPH). In this study, we tested predictions of these three hypotheses regarding territories of 19 packs of endangered African wild dogs (Lycaon pictus) over 2 years in the Kruger National Park, South Africa. If territory size was supported by the RDH, then we would observe (1) wild dog territories would be larger when resource patches were more dispersed, (2) pack sizes would be larger when resource patches were rich, and (3) pack size would not affect territory size. If supported by the IPH, then we would observe (4) larger territories would experience less intrusions, and (5) there would be an increase in territory overlap in areas of low resource dispersion. Finally, if supported by the IGPH, we would observe (6) territories would be larger in areas of higher lion (Panthera leo) density, as evidence of a spatial avoidance strategy. We found that the IGPH was fully supported (6), the IPH half supported (5), and the RDH partially supported (1 and 3), where we found spatial partitioning of wild dogs with lions, potentially mediated by resources and territory overlap with conspecifics. Ultimately, our results show that subordinate carnivores must balance a trade-off between dominant interspecific competitors and conspecifics to successfully coexist in areas with dominant carnivores.South African National Parks (SANParks) honorary rangers and the Endangered Wildlife Trust (EWT).http://link.springer.com/journal/4422020-09-18hj2020Mammal Research InstituteZoology and Entomolog

Temporal patterns of den use suggest polygamous mating patterns in an obligate monogamous mammal

Mating systems in animal societies contain both social and genetic components. Deviations between these components may have important ramifications for our understanding of the evolution of animal reproductive strategies and their ecological correlates. However, although there is ample evidence for discrepancies between genetically assigned paternities and social associations in birds, relatively few studies have documented such differences in mammals. Moreover, few studies have addressed how deviations between social mating associations and actual mating activities influence patterns of resource utilisation in males and females. The aardwolf is a socially monogamous hyaenid that exhibits polygamous mating behaviour. Suitable den sites for resting and rearing offspring is an important resource for terrestrial mammals, and dens are vital to aardwolves as thermal refugia for protection of offspring. We show that temporal patterns in aardwolf den use relates to predictions from polygamous mating rather than social monogamy. Male aardwolves used more dens, changed dens more frequently and stayed in dens for shorter periods of time than females during both wet and dry seasons. We suggest that lower male den fidelity is either caused by males trying to maximize female encounters and to monitor female activity, or that it had evolved as a non-adaptive behaviour related to elevated androgen levels. Our data did not point to territorial defence or space use optimization as cause for the observed sex differences, since we did not find any sex or seasonal differences in the spatial patterns of utilized dens. We suggest that aardwolves may have been ecologically constrained to exhibit social monogamy but that polymagous mating is maintained through extra pair copulations. We recommend that the evolutionary stability of these two conflicting strategies of male fitness maximization must be further investigated.An NRF focal area grant (EZC), NRF incentive funds (CWWP, FD), an NRF SARCHi chair in mammal behavioural ecology and physiology (NCB) and a research fellowship from University of Pretoria (FD).http://www.elsevier.com/locate/anbehavhb2016Centre for Wildlife ManagementMammal Research InstituteZoology and Entomolog

The first report of urine overmarking of pro-oestrus female dung by a male white rhino

Although observed in other Perrisodactyla, urine overmarking in white rhinos has not been described. Using a single opportunistic sighting, we were able to collect two dung samples from one oestrous female white rhino; one unmarked and one overmarked with male urine. Because of the behaviour of both the male and the female, we suggest that the female was in pro-oestrus. We hypothesised that the function of overmarking by the male was for oestrus concealment (i.e. odour masking), as observed in horses. Because dung from oestrous female white rhinos emits a higher proportion of alkanes than non-oestrous dung, we expected the proportion of alkanes emitted from oestrous dung to decrease after overmarking. In contrast, we found that after overmarking the proportion of alkanes emitted increased. We suggest that the function of urine overmarking in white rhinos could be to conceal all signals of reproductive condition, so that neither oestrous nor non-oestrous signals are recognisable, or that a signal is added to indicate that the female has been mated.Keywords: Ceratotherium simum, odour masking, oestrus concealmen

Protecting the protected through assessing driver behaviour In Kruger National Park, South Africa

Growing concern about the ecological effects of roads has led to the emergence of a new scientific discipline called road ecology. The goal of road ecology is to provide planners with scientific advice on how to minimise or mitigate negative environmental impacts of transportation. To date, South African road ecology studies have focused primarily on roadkill rates, with results highlighting the need not only for a greater understanding of the primary determinants of roadkill and its threat to biodiversity, but also the indirect effects of the country’s roads on wildlife. Direct collision is the most evident impact due to its visual nature, but the disruption of ecological processes is equally important. Loss of habitat, habitat fragmentation, degradation of habitat, road and railway avoidance, increased human exploitation, reduced access to habitats, population fragmentation and disruption of processes which maintain regional populations are just some of the ways in which roads can affect biodiversity. Notwithstanding, collisions with large mammals are also a threat to human safety and represent an economic cost to society. South Africa’s protected areas are the prime custodians of biodiversity, for which tourism is an important revenue earner, currently accounting for 7.9% of GDP and supporting one in every 12 jobs in South Africa. With approximately 10 million visitors per year, wildlife is a key product of protected areas and highly sought after by visitors. However, with large numbers of visitors, Wildlife-Vehicle Collisions (WVCs) commonly occur. Tourism is expected to grow significantly in South Africa by 2020, leading to more vehicles within protected areas and the potential for more WVCs. In 2014, the Endangered Wildlife Trust initiated a six-year project in response to social media discussions which highlighted public concern for WVCs inside protected areas. Six protected areas in South Africa were identified for the project, reflecting different biomes, road types and visitor volumes, to examine the impacts of roads and driver behaviour on wildlife mortality in protected areas. Research has already been undertaken in Pilanesberg and Addo National Parks, with current research ongoing in Dinokeng Game Reserve and Kruger National Park. Innovative strategies are required to minimise the ecological impact of roads as well as improve people’s livelihoods. We investigated factors affecting the likelihood of WVCs within Kruger National Park, and assessed the comparative effectiveness of wildlife-warning signage (WWS) for altering driver behaviour. We laid a dummy snake on straight paved roads and recorded 10 driver-related variables for 100 vehicles that passed, or collided with the dummy snake. Further to this, we then investigated the effectiveness of signage in modifying driver behaviour by erecting six variations of WWS, depicting either a snake, kudu, cheetah and a speed camera. We positioned the dummy snake 100 m after the signage and recorded our 10 variables (n = 400 vehicles). We discuss our findings from Kruger National Park and compare this to research already undertaken in Pilanesberg National Park. In the latter park, 61% of drivers who passed a WWS changed their behaviour when they saw the dummy snake, compared to 37% with no sign present. Further, this behaviour change significantly reduced collisions, with 98% of drivers positively altering their behaviour and generally abiding by the recommended speed limit (40 km/h). By comparison, drivers in Kruger National Park often exceeded park speed limits when no WWS was present but did modify their behaviour with the presence of a WWS. The collective findings of the project will contribute towards a traffic management plan for protected areasPapers presented at the 38th International Southern African Transport Conference on "Disruptive transport technologies - is South and Southern Africa ready?" held at CSIR International Convention Centre, Pretoria, South Africa on 8th to 11th July 2019

Factors affecting the success of artificial pack formation in an endangered, social carnivore: the African wild dog

Social integration is an important factor when reintroducing group-living species, but examples of the formation of social groups before reintroduction are largely lacking. African wild dogs Lycaon pictus are endangered, and reintroductions have become a routine part of range expansion in South Africa. Wild dogs form packs that are essential to their reproduction and survival, and artificial pack formation is often required before reintroduction. We examined the proximate (i.e. social integration) and ultimate (i.e. reproduction) success of 43 artificial pack formation attempts in the South African managed metapopulation, between 1995 and 2018. The top (and dominant) model for proximate success included an interaction between total group size and an initial separation fence. Larger groups took longer to integrate, irrespective of initial separation, whereas smaller groups brought together immediately integrated faster than those that were initially separated. The top models for ultimate success included an interaction between the proportion of males and number of days spent in the pre-release enclosure, the total number of days in the enclosure and an interaction between the proportion of captive-sourced individuals and the total number of days in the enclosure. Ultimate success increased when packs spent less time in the enclosure, especially if those packs had a low proportion of males (i.e. female biased) or included >25% captive-sourced individuals. Neither the size of the artificially created pack nor the season in which the pack was released affected ultimate success. The success of social integration and reproductive success of artificially formed packs in this study was higher than for natural pack formations. We provide guidelines for optimizing future artificial pack formation in wild dogs for reintroduction success. Our results serve as an example of the practical importance of social behavior in successfully implementing conservation measures for group-living species

Factors affecting the success of artificial pack formation in an endangered, social carnivore: the African wild dog

Social integration is an important factor when reintroducing group-living species, but examples of the formation of social groups before reintroduction are largely lacking. African wild dogs Lycaon pictus are endangered, and reintroductions have become a routine part of range expansion in South Africa. Wild dogs form packs that are essential to their reproduction and survival, and artificial pack formation is often required before reintroduction. We examined the proximate (i.e. social integration) and ultimate (i.e. reproduction) success of 43 artificial pack formation attempts in the South African managed metapopulation, between 1995 and 2018. The top (and dominant) model for proximate success included an interaction between total group size and an initial separation fence. Larger groups took longer to integrate, irrespective of initial separation, whereas smaller groups brought together immediately integrated faster than those that were initially separated. The top models for ultimate success included an interaction between the proportion of males and number of days spent in the pre-release enclosure, the total number of days in the enclosure and an interaction between the proportion of captive-sourced individuals and the total number of days in the enclosure. Ultimate success increased when packs spent less time in the enclosure, especially if those packs had a low proportion of males (i.e. female biased) or included >25% captive-sourced individuals. Neither the size of the artificially created pack nor the season in which the pack was released affected ultimate success. The success of social integration and reproductive success of artificially formed packs in this study was higher than for natural pack formations. We provide guidelines for optimizing future artificial pack formation in wild dogs for reintroduction success. Our results serve as an example of the practical importance of social behavior in successfully implementing conservation measures for group-living species