Harriet T. Davies-Mostert

Rates and causes of mortality in Endangered African wild dogs Lycaon pictus: Lessons for management and monitoring

Effective species conservation depends upon correctly identifying the threats that cause decline or hinder recovery. Because estimates of the relative viability of different populations of Endangered African wild dogs Lycaon pictus are most strongly influenced by adult and pup mortality, we analysed rates and causes of mortality in eight wild dog populations under study in southern and eastern Africa. The probabilities of detecting wild dog deaths were influenced by the monitoring methods used. The least biased estimates of mortality causes were obtained through intensive monitoring of radio-collared individuals; this is impossible for pups, however. Mortality patterns varied substantially between populations. Rates of human-caused mortality were higher for wild dogs radio-collared outside protected areas than for those collared inside, but rates of natural mortality were comparable, suggesting that anthropogenic mortality is additive to natural mortality. The relative importance of factors such as snaring and infectious disease also varied regionally. Hence, although our analyses identified no new threats beyond those highlighted in a 1997 range-wide Action Plan, they suggest that local plans will be valuable to target conservation activities more precisely.

Minimum prey and area requirements of the Vulnerable cheetah Acinonyx jubatus: implications for reintroduction and management of the species in South Africa

In South Africa there are efforts to manage reintroduced subpopulations of the Vulnerable cheetah Acinonyx jubatus in small reserves (10-1,000 km 2 )a s a managed metapopulation. We estimated areas required to support cheetahs given varying prey densities, prey profiles and presence/absence of competing predators. A recent population and habitat viability assessment in- dicated that 20 subpopulations of 10 cheetahs or 10 sub- populations of 15 cheetahs are required to retain 90% of the heterozygosity of free-ranging cheetahs and to overcome stochastic events in the absence or presence of lions Panthera leo, respectively. We estimate that 203 - SE 42 km 2 (range 48-466 km 2 ) is required to support 10 cheetahs in the absence of lions, whereas 703 - SE 311 km 2 (166-2,806 km 2 ) is required to support 15 cheetahs given equal numbers of lions, and 2,424 - SE 890 km 2 (727-3,739 km 2 ) given equal numbers of leopards Panthera pardus, spotted hyaenas Crocuta crocuta, wild dogs Lycaon pictus and lions. Existing subpopulations of cheetahs generally occur at densities higher than our mean predicted densities but usually within the range of predicted densities. The large area requirements of cheetahs have implications for the development of the managed metapopulation. Sourcing reintroduction sites of the sizes required to support recommended subpopulation sizes will be difficult. Consequently, innovative measures to increase the carrying capacity of reserves for cheetahs and/or to enlarge reserves will be required. Managers may be forced to stock cheetahs close to or beyond the carrying capacity of their reserves. Consequently, careful management of rein- troduced subpopulations will be required to prevent declines in prey populations.

Evaluating the Status of and African Wild Dogs Lycaon pictus and Cheetahs Acinonyx jubatus through Tourist-based Photographic Surveys in the Kruger National Park

The Kruger National Park is a stronghold for African wild dog Lycaon pictus and cheetah Acinonyx jubatus conservation in South Africa. Tourist photographic surveys have been used to evaluate the minimum number of wild dogs and cheetahs alive over the last two decades. Photographic-based capture-recapture techniques for open populations were used on data collected during a survey done in 2008/9. Models were run for the park as a whole and per region (northern, central, southern). A total of 412 (329–495; SE 41.95) cheetahs and 151 (144–157; SE 3.21) wild dogs occur in the Kruger National Park. Cheetah capture probabilities were affected by time (number of entries) and sex, whereas wild dog capture probabilities were affected by the region of the park. When plotting the number of new individuals identified against the number of entries received, the addition of new wild dogs to the survey reached an asymptote at 210 entries, but cheetahs did not reach an asymptote. The cheetah population of Kruger appears to be acceptable, while the wild dog population size and density are of concern. The effectiveness of tourist-based surveys for estimating population sizes through capture-recapture analyses is shown.

The effect of protected areas on pathogen exposure in endangered African wild dog (Lycaon pictus) populations

Abstract Infectious diseases impact African wild dogs (Lycaon pictus), but the nature and magnitude of this threat likely varies among populations according to different factors, such as the presence and prevalence of pathogens and land-use characteristics. We systematically evaluated these factors to assist development of locally appropriate strategies to mitigate disease risk. Wild dogs from 16 sites representing five unconnected populations were examined for rabies virus, canine distemper virus (CDV), canine parvovirus, canine coronavirus, and Babesia spp. exposure. Analyses revealed widespread exposure to viral pathogens, but Babesia was never detected. Exposure to CDV was associated with unprotected and protected-unfenced areas where wild dogs likely have a high probability of domestic dog contact and, in the case of protected-unfenced areas, likely reside amongst high wildlife densities. Our findings also suggest that domestic dog contact may increase rabies and coronavirus exposure risk. Therefore, domestic dogs may be a source of CDV, rabies and coronavirus, while wildlife may also play an important role in CDV transmission dynamics. Relatively high parvovirus seroprevalence across land-use types suggests that it might persist in the absence of spillover from domestic dogs. Should intervention be needed to control pathogens in wild dogs, efforts to prevent rabies and coronavirus exposure might be directed at reducing infection in the presumed domestic dog reservoir through vaccination. If prevention of CDV and parvovirus infections were deemed a management necessity, control of disease in domestic dogs may be insufficient to reduce transmission risks, and vaccination of wild dogs themselves may be the optimal strategy.

Wildlife road traffic accidents: a standardized protocol for counting flattened fauna

Previous assessments of wildlife road mortality have not used directly comparable methods and, at present, there is no standardized protocol for the collection of such data. Consequently, there are no internationally comparative statistics documenting roadkill rates. In this study, we used a combination of experimental trials and road transects to design a standardized protocol to assess roadkill rates on both paved and unpaved roads. Simulated roadkill were positioned over a 1 km distance, and trials were conducted at eight different speeds (20–100 km·h−1). The recommended protocol was then tested on a 100-km transect, driven daily over a 40-day period. This recorded 413 vertebrate roadkill, comprising 106 species. We recommend the protocol be adopted for future road ecology studies to enable robust statistical comparisons between studies.

Habitat selection by transient African wild dogs (Lycaon pictus) in northern KwaZulu-Natal, South Africa : implications for range expansion

Reintroductions of African wild dogs (Lycaon pictus) in the KwaZulu-Natal Province, through the managed metapopulation approach, promoted a population expansion from one pack in Hluhluwe-iMfolozi Park in 1997 to nine packs in three reserves by 2009. Consequently, the likelihood of dispersing wild dogs leaving their natal ranges from within fenced reserves also increased. Land outside these reserves could potentially be utilized to expand wild dog distribution and provide connectivity between the geographically isolated subpopulations. We used Maximum Entropy Modelling (Maxent) to characterize habitat niche selection of transient wild dogs outside of resident reserves, and to identify potential dispersal linkages between subpopulations. A habitat suitability model indicated four variables (elevation, land cover, road density and human density) best predicted probability of presence for transient wild dogs. Elevation (AUC > 0.80) and land cover (AUC > 0.75) were the two most influential variables when considered independently. Transient wild dogs preferred lower lying locations (130–330 m a.s.l.) covered by woodland or bushland; habitat indicative of the preferred prey of wild dogs. Considerable habitat exists for subpopulation linkages; however, the majority of wild dog movements between subpopulations required mitigation of potential or real game or livestock losses. Development of formal linkages and wild dog management between subpopulations will require a sustained approach to improving tolerance towards wild dogs, clarity on financial obligations and management responses to pack and prey population dynamics.

Attitudes of Rural Communities Toward Dispersing African Wild Dogs in South Africa

Subsistence pastoralists often view large carnivores negatively given that any loss of livestock is likely to represent a significant economic cost. Consequently, large carnivore conservation initiatives in rural landscapes should incorporate appropriate human–carnivore conflict mitigation strategies. In this study, structured interviews with local residents (n = 247) were used for determining attitudes toward African wild dogs (Lycaon pictus) among rural communities neighboring two protected areas in KwaZulu-Natal, South Africa. Contrary to expectations, the majority of respondents (58%) were generally positive toward wild dogs. This was probably due to a lack of livestock depredation by wild dogs and relatively high levels of formal education among respondents. Respondents with greater knowledge of wild dogs and conflict mitigation had more positive attitudes, and most were aware of effective husbandry techniques. The positive attitudes observed in these rural communities may benefit wild dog dispersal from natal home ranges and the future conservation of this endangered carnivore.

The demography and dynamics of an expanding, managed African wild dog metapopulation

Long-term demographic data are central for the evaluation of endangered species recovery plans. We present the demography and dynamics of a managed African wild dog (Lycaon pictus) metapopulation in South Africa, based on life histories of 553 individually known animals collected between 1998 and 2006. This metapopulation, distributed across nine sites (and not including Kruger National Park), was established through reintroductions (n = 9 events) and maintained by periodic augmentation (n = 10 events) and translocation (n = 20 events). In total, 66 founders were used to establish subpopulations and mean founder group size was 9.6 animals. The metapopulation grew from 17 individuals in 1998 to a peak of 202 in 2005. Mean annual population density was 3.3 (S.E. 0.44) wild dogs/100 km2, approaching the upper limit of densities reported from unmanaged populations. Mean size of breeding packs was 11.0 (S.E. 0.76), comparable to pack sizes in Kruger National Park (Kruger), the only viable unmanaged population in South Africa. Fecundity was lower than in Kruger — particularly in the older age classes. Pup survival to adulthood was 45% — nearly three times the survival rate for pups in Kruger. Mean annual population growth rate (&lgr; = 1.08, S.E. 0.13) was higher than in unmanaged populations (range 1.000–1.038), with implications for population viability and management.

Heading for the hills: risk avoidance drives den site selection in African wild dogs.

Compared to their main competitors, African wild dogs (Lycaon pictus) have inferior competitive abilities and interspecific competition is a serious fitness-limiting factor. Lions (Panthera leo) are the dominant large carnivore in African savannah ecosystems and wild dogs avoid them both spatially and temporally. Wild dog young are particularly vulnerable and suffer high rates of mortality from lions. Since lions do not utilize all parts of the landscape with an equal intensity, spatial variation in lion densities can be exploited by wild dogs both during their general ranging behaviour, but more specifically when they are confined to a den with vulnerable young. Since patches of rugged terrain are associated with lower lion densities, we hypothesized that these comparatively safe habitats should be selected by wild dogs for denning. We investigated the relationship between the distribution of 100 wild dog den sites and the occurrence of rugged terrain in four wild dog populations located in Tanzania, Zimbabwe and South Africa. A terrain ruggedness index was derived from a 90 m digital elevation model and used to map terrain ruggedness at each site. We compared characteristics of actual and potential (random) den sites to determine how wild dogs select den sites. The distributions of wild dog dens were strongly associated with rugged terrain and wild dogs actively selected terrain that was more rugged than that available on average. The likelihood of encountering lions is reduced in these habitats, minimizing the risk to both adults and pups. Our findings have important implications for the conservation management of the species, especially when assessing habitat suitability for potential reintroductions. The simple technique used to assess terrain ruggedness may be useful to investigate habitat suitability, and even predict highly suitable denning areas, across large landscapes.

Reducing potential sources of sampling bias when quantifying the diet of the African wild dog through scat analysis

To develop guidelines for the collection of independent field samples of scats for the quantification of wild dog (Lycaon pictus) diet we determined the passage rates of different wild dog prey items from feeding trials on a captive pack held at Marakele National Park, Limpopo Province. The minimum time to first detection was 5.5 hours after feeding (S.E. ± 1.52, n = 5) and prey items remained in the gut for an average of 79.4 hours (S.E. ± 6.00, n = 3). Differential passage rates of prey species were not pronounced. Observed passage rates were used to devise a sampling protocol for scats collected during a field study where scats were separated by a minimum period of 120 hours to ensure independence of samples. Comparison of the percentage occurrence of prey species in field-collected scats with the percentage occurrence from direct observations of kills illustrated the tendency for small prey to be underrepresented in the latter. However, the strong correlation between percentage occurrences in diet as determined by the two methods (r s = 0.85, P < 0.01, 13 d.f.) suggests that both methods can reliably determine the relative importance of prey in the diets of obligate carnivores such as wild dogs. The determination of maximum passage rates and subsequent guidelines for collection of independent faecal samples in the field could be a valuable tool for reducing inherent biases in carnivore diet studies.