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 from17 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 (ë = 1.08, S.E. 0.13) was higher than in unmanaged populations (range 1.000–1.038), with implications for population viability and management.H.D.M. was supported through grants to D.W.M. from Fauna & Flora International and Siren. Fieldwork was supported by the Endangered Wildlife Trust, De Beers Consolidated Mines and Jaguar Land Rover South Africa.http://www.sawma.co.zaam201

Behavioural adjustments of a large carnivore to access secondary prey in a human-dominated landscape

1. Conflict between people and large carnivores is an urgent conservation issue world-wide. Understanding the underlying ecological drivers of livestock depredation by large carnivores is greatly needed. 2. We studied the spatial, foraging and behavioural ecology of African lions Panthera leo in the Botswana Makgadikgadi ecosystem. This ecosystem comprises a protected area, characterized by high seasonal fluctuation in wild prey abundance, and adjacent lands, which are used for livestock grazing and characterized by stable livestock abundance, but also a risk of anthropogenic mortality. 3. Makgadikgadi lions preferentially preyed upon migratory wild herbivores when they were present; however, data from GPS (Global Positioning System) radiocollared lions revealed that the majority of the study lions did not follow the migratory herds but remained resident at one or other border of the park and switched to livestock (abundant and readily available), and to a lesser extent resident wild herbivores (relatively scarce), in periods of migratory wild herbivore scarcity. 4. Resident lions’ use of space differed between periods of wild prey abundance and scarcity. These changes were likely to increase the frequency of encounter with their primary prey in periods of primary prey abundance and with livestock in periods of primary prey scarcity. 5. The risk of conflict with humans was a major driver of lion ecology in the human-dominated landscape surrounding the protected area. Resident lions generally avoided the close vicinity of cattle- posts.When they used such areas, they avoided temporal overlap with periods that humans were most active and travelled at high speed reducing the time spent in these areas. 6. Synthesis and applications. This study suggests that lions balance the benefits of accessing livestock with the costs associated with livestock raiding. Hence, reduction in livestock availability through effective livestock husbandry in periods of wild prey scarcity should lead to reduced conflict.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-2664ab201

Social systems and behaviour of the African wild dog Lycaon pictus and the spotted hyaena Crocuta crocuta with special reference to rabies

Differences in the social systems and behaviour of two potentially important hosts of rabies, the African wild dog and the spotted hyaena, may lead to differences in the epizootiology of the disease in the two species. Wild dogs are highly social animals in which pack members are in constant physical contact with each other, but in which inter-pack interactions are rare. Spotted hyaenas are more flexible in their social systems and behaviour. Clan members interact less frequently than do wild dogs, but inter-clan contact rates may be high in high density populations. Rabies transmission within wild dog packs should be rapid, but rare between packs. In spotted hyaenas rabies transmission between clan members may partially depend on the social status of the animals involved and between packs on the density of hyaenas in the area.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.National Parks Board. Endangered Wildlife Trust. Stuart Bromfield Wild Dog Fund.mn201

The feeding habits of the South African wildcat, a facultative trophic specialist, in the southern Kalahari (Kgalagadi Transfrontier Park, South Africa/Botswana)

The seasonal feeding habits of the Southern African wildcat Felis silvestris cafra in the riverbed ecotone of the Kgalagadi Transfrontier Park were investigated over a period of 46 months. The diet was analysed through visual observations on eight habituated (three females and five males) radio-collared wildcats, supplemented with scat analysis. Murids formed the bulk of the biomass in the diet (73%), followed by birds (10%) and large mammals (>500 g) (9%). Although reptiles (6%) and invertebrates (2%) were frequently caught, they contributed less to the overall biomass of the diet. There were significant seasonal differences in the consumption of five food categories that related to changes in availability. Fluctuations in prey abundances could be the result of seasonal rainfall and temperature fluctuations or long-term variability in rainfall resulting in wet and dry cycles. As predicted, the lean season (hot-dry) was characterized by a high food-niche breadth and a high species richness. Despite sexual dimorphism in size in the Southern African wildcat, both sexes predominantly fed on smaller rodents, although there were differences in the diet composition, with males taking more large mammals and females favouring birds and reptiles. These results indicate that Southern African wildcats are adaptable predators that prefer to hunt small rodents, but can change their diet according to seasonal and longer-term prey abundances and availability.This research was supported by the Endangered Wildlife Trust's Carnivore Conservation Group (South Africa), the Elizabeth Wakemen Henderson Charitable Foundation, the Mammal Research Institute and the Molecular Ecology and Evolution Program (Department of Genetics) at the University of Pretoria, the National Research Foundation (South Africa), the Kaplan Awards Program from Wildlife Conservation Society and the Skukuza Marathon Club

Techniques used in the study of African wildcat, Felis silvestris cafra, in the Kgalagadi Transfrontier Park (South Africa / Botswana)

The techniques used for the capture, marking and habituation of African wildcats (Felis silvestris cafra) in the Kalahari are described and evaluated in this paper. African wildcats were captured, with either baited cage traps or chemical immobilisation through darting. Darting proved to be a more efficient and less stressful way of capturing cats. Very high frequency (VHF) radio collars fitted with activity monitors were especially effective in the open habitat of the Kalahari for locating and maintaining contact with cats; they also aided in determining if the cats were active or resting in dense vegetation. The habituation of individual cats to a 4×4 vehicle proved to be time consuming, but it provided a unique opportunity to investigate the feeding ecology and spatial organisation of cats through direct visual observations. Conservation implications: In describing and comparing the various methods of capture, handling and release of the African wildcats that we followed during our study in the southern Kalahari, we recommend the most efficient, least stressful method for researchers to follow – both in relation to time and energy, as well as in terms of the impact on the animals being studied

Predator–prey size relationships in an African large-mammal food web

Size relationships are central in structuring trophic linkages within food webs, leading to suggestions that the dietary niche of smaller carnivores is nested within that of larger species. However, past analyses have not taken into account the differing selection shown by carnivores for specific size ranges of prey, nor the extent to which the greater carcass mass of larger prey outweighs the greater numerical representation of smaller prey species in the predator diet. Furthermore, the top-down impact that predation has on prey abundance cannot be assessed simply in terms of the number of predator species involved. Records of found carcasses and cause of death assembled over 46 years in the Kruger National Park, South Africa, corrected for under-recording of smaller species, enabled a definitive assessment of size relationships between large mammalian carnivores and their ungulate prey. Five carnivore species were considered, including lion (Panthera leo), leopard (Panthera pardus), cheetah (Acinonyx jubatus), African wild dog (Lycaon pictus) and spotted hyena (Crocuta crocuta), and 22 herbivore prey species larger than 10 kg in adult body mass. These carnivores selectively favoured prey species approximately half to twice their mass, within a total prey size range from an order of magnitude below to an order of magnitude above the body mass of the predator. The three smallest carnivores, i.e. leopard, cheetah and wild dog, showed high similarity in prey species favoured. Despite overlap in prey size range, each carnivore showed a distinct dietary preference. Almost all mortality was through the agency of a predator for ungulate species up to the size of a giraffe (800–1200 kg). Ungulates larger than twice the mass of the predator contributed substantially to the dietary intake of lions, despite the low proportional mortality inflicted by predation on these species. Only for megaherbivores substantially exceeding 1000 kg in adult body mass did predation become a negligible cause of mortality. Hence, the relative size of predators and prey had a pervasive structuring influence on biomass fluxes within this large-mammal food web. Nevertheless, the large carnivore assemblage was dominated overwhelmingly by the largest predator, which contributed the major share of animals killed across a wide size range

Shifting prey selection generates contrasting herbivore dynamics within a large-mammal predator-prey web

Shifting prey selection has been identified as a mechanism potentially regulating predator–prey interactions, but it may also lead to different outcomes, especially in more complex systems with multiple prey species available. We assessed changing prey selection by lions, the major predator for 12 large herbivore species in South Africa’s Kruger National Park. The database was provided by records of found carcasses ascribed to kills by lions assembled over 70 years, coupled with counts of changing prey abundance extending over 30 years. Wildebeest and zebra constituted the most favored prey species during the early portion of the study period, while selection for buffalo rose in the south of the park after a severe drought increased their vulnerability. Rainfall had a negative influence on the proportional representation of buffalo in lion kills, but wildebeest and zebra appeared less susceptible to being killed under conditions of low rainfall. Selection by lions for alternative prey species, including giraffe, kudu, waterbuck, and warthog, was influenced by the changing relative abundance and vulnerability of the three principal prey species. Simultaneous declines in the abundance of rarer antelope species were associated with a sharp increase in selection for these species at a time when all three principal prey species were less available. Hence shifting prey selection by lions affected the dynamics of herbivore populations in different ways: promoting contrasting responses by principal prey species to rainfall variation, while apparently being the main cause of sharp declines by alternative prey species under certain conditions. Accordingly, adaptive responses by predators, to both the changing relative abundance of the principal prey species, and other conditions affecting the relative vulnerability of various species, should be taken into account to understand the interactive dynamics of multispecies predator–prey webs

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 (rs = 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

Flexible energetics of cheetah hunting strategies provide resistance against kleptoparasitism

Carnivores are considered to operate close to maximum sustained power outputs, and so may be particularly vulnerable to decreased food availability, kleptoparaasitism or increased activity. We measured daily energy expenditure (DEE) in cheetahs and found that they had similar values similar to size-based predictions and spent most energy simply walking, rather than chasing prey