M. G. L. Mills

Wildlife viewing preferences of visitors to protected areas in South Africa: implications for the role of ecotourism in conservation.

Ecotourism has a potentially vital role to play in conservation by generating economic incentives for nature conservation. However, some authors contend that this potential may be limited by narrow viewing preferences among visitors to protected areas, suggesting that most tourists are primarily interested in seeing charismatic mega-fauna largely confined to government or privately-owned parks. We assessed viewing preferences among tourists at four protected areas in South Africa to test the validity of this contention. Mega-herbivores and large carnivores were the most popular species, particularly among first-time and overseas visitors, but African visitors and experienced wildlife viewers were more interested in bird and plant diversity, scenery, and rarer, less easily-observed and/or less high-profile mammals. Several of these favored species are extinction prone and often absent from wildlife areas due to sensitivity to human encroachment and competition with more abundant species. Hence, ecotourism may provide incentives for the conservation of intact guilds, and management for ecotourism may align more closely with biodiversity conservation objectives than suggested by critics. This potential could be enhanced by diversification of tour operator advertising to feature aspects of biodiversity other than the ‘big five’. Nonetheless, charismatic mega-fauna have a vital flagship role by attracting most overseas and first-time visitors to protected areas.

Factors affecting the hunting success of male and female lions in the Kruger National Park

Long-term continuous observations of hunting lions Panthera leo in the Kruger National Park were used to assess the variables affecting hunting success of male and female lions. Generalized linear models revealed that seven variables had significant independent influences on hunting success, with the most important being the prey species hunted. Three types of variables were recognized: (1) lion related, where type of hunt, wind orientation, and the number of adults hunting; (2) prey related, where prey species and herd size; (3) environment related, where moon brightness, and grass height were significant. The sex of the lions had no effect on the overall probability of hunting success. Five second-order interactions significantly influenced the probability of hunting success, with the most important being the interaction between sex and the type of prey. The only significant third-order interaction containing the variable sex, was the inter-relationship with prey species and shrub cover. After removing the over-riding bias of the prey species, greater resolution of the factors affecting success was revealed. The major difference was that group size influences hunting success and concomitantly prey selection, promoting selection for medium-sized ungulates like zebra Equus burchelli and wildebeest Connochaetes taurinus by females, and males mainly capturing buffalo Syncerus caffer. We conclude that in African ecosystems, the hunting success of male and female lions varies with a range of combinations of lion-, prey- and environment-related variables. We demonstrate the hunting ability of male lions, which has perhaps been understated in other studies.

Cheetah Acinonyx jubatus feeding ecology in the Kruger National Park and a comparison across African savanna habitats: is the cheetah only a successful hunter on open grassland plains?

The literature on cheetah Acinonyx jubatus ecology is dominated by studies on the Serengeti Plains (SNP) in East Africa. Because of this and the cheetahs hunting strategy it is generally considered to be a predator that prefers open grassland plains. However, cheetahs also inhabit a range of bush, scrub and woodland habitats. A field study using direct observations of radio-collared individuals in the woodland savanna habitat of the Kruger National Park (KNP), South Africa, and a literature review of studies across savanna habitats examined cheetah predation, hunting behaviour and habitat use in relation to prey composition, cover availability and kleptoparasitism. The cheetahs main prey is medium-sized herbivores, with a bias towards male prey. The group size and sex of the hunting cheetah may influence the results of prey selection studies as male coalitions tend to take larger prey than females. Cheetahs initiated more hunts and had a higher success rate in the open woodland savanna of the KNP compared to other available habitats with thicker bush, and in other wooded savanna areas they also prefer more open habitat for hunting. Although they appear to have shorter chase distances in more wooded habitats, hunting success appears to be slightly higher in open grassland habitat. Woody vegetation appears to obstruct the cheetahs high-speed hunting strategy, thereby lowering hunting success. However, cheetahs use cover for stalking prey and open habitats with bordering woodlands, or patches of cover are considered preferred cheetah habitats. In these habitats, cheetahs can stalk closer to their prey using available cover, but also successfully pursue their prey into available open spaces. Across African savanna ecosystems, cheetahs appear to be kleptoparasitised less in more wooded habitats. Therefore they may also prefer these habitats because they provide greater concealment from kleptoparasites. Our study suggests that the cheetah is more adaptable to habitat variability than is often thought and is not only a successful hunter on open grassland plains.

Aspects of the management of cheetahs, Acinonyx jubatus jubatus, trapped on Namibian farmlands

Abstract The Namibian cheetah population has recently undergone serious decline due to human-mediated removals, and investigating the rates and causes of such removals is an important aspect of the future management of cheetah populations outside protected areas. We examined cheetahs that were reported live-trapped or killed on Namibian farmlands between 1991 and 1999. A perceived threat to livestock or game led to the vast majority of live captures and to almost half of the cheetah deaths investigated. Despite this, livestock predation from cheetahs appeared to be minimal, and was usually perpetrated by cheetahs with injuries. Most of the cheetahs were trapped in groups, and cheetahs’ relative sociality leads to the easy removal of entire social units. Long-term monitoring must include detailed consideration of these indiscriminate removals, as they involve many cheetahs, fluctuate between years, often go unreported, and are likely to have a serious impact on cheetah populations outside protected areas.

Demography of the Namibian cheetah, Acinonyx jubatus jubatus

Abstract Namibian cheetahs have suffered, and continue to suffer, high levels of removal due to conflict with local farmers, and it is important to understand the demography of this population in order to determine its likely persistence. Examination of cheetahs reported live-trapped or killed by local farmers, combined with subsequent information from radio-telemetry, allowed demographic parameters such as sex ratios, age and social structure, litter size, interbirth intervals and survivorship to be estimated for cheetahs on Namibian farmlands. Cub mortality was relatively low, but adult mortality was high, particularly for males, and peaked at 5–6 years of age. Neither marking nor relocating cheetahs seemed to affect survivorship, and there was no difference in survivorship between the sexes. Time spent in captivity did not appear to affect survival after release. These findings will be useful in formulating recommendations regarding the conservation and sustainable utilization of cheetah populations outside protected areas.

Sexual and seasonal variation in the diet and foraging behaviour of a sexually dimorphic carnivore, the honey badger ( Mellivora capensis )

The honey badger, or ratel, Mellivora capensis has not been well studied despite its extensive distribution. As part of the first detailed study, visual observations of nine habituated free-living individuals (five females, four males) were used to investigate seasonal, annual and sexual differences in diet and foraging behaviour. Theory predicts that generalist predators ‘switch’ between alternative prey species depending on which prey species are currently most abundant, and diet breadth expands in response to decreased availability of preferred food types. There were significant seasonal differences in the consumption of eight prey categories related to changes in prey availability but no seasonal differences in food intake per kg of body mass. As predicted, the cold-dry season diet was characterized by low species richness and low foraging yield but high dietary diversity, while the reverse wa st ru ei nt he hot-dry and hot-wet seasons. In accordance with these predictions, results suggest that the honey badger maintains its intake level by food switching and by varying dietary breadth. Despite marked sexual size dimorphism, male and female honey badgers showed no intersexual differences in prey size, digging success, daily food intake per unit body weight or foraging behaviour. Results do not support the hypothesis that size dimorphism is primarily an adaptation to reduce intersexual competition for food.

Spatial organization of the honey badger Mellivora capensis in the southern Kalahari: home‐range size and movement patterns

Radio-tracking locations of 25 individuals (13 females; 12 males) and visual observations of nine habituated individuals were used to investigate the spatial organization and movement patterns of the honey badger Mellivora capensis in the southern Kalahari. The home ranges of adult male honey badgers (541 ± 93 km2) were significantly larger than the home ranges of adult females (126 ± 13 km2). Female home-range size was five times larger than predicted from body mass. The extensive home ranges of females were likely to be a function of relatively low prey availability in the semi-arid Kalahari and the long period of cub dependence (12–16 months). While mean home-range overlap in females was moderate (13%) and home-range centres were regularly spaced, females did not appear to actively defend a territory and no direct interactions between females were observed. Scent marking appears to mediate spatio-temporal separation and females show a loosely territorial spacing pattern. In contrast, males did not support the typical mustelid pattern of intra-sexual territoriality but instead encompassed the overlapping home ranges of up to 13 females. Males and females differed significantly in their rate of travel (3.8 ± 0.3 km/h vs 2.7 ± 0.2km/h), straight line (6.2 ± 0.5 km vs 2.4 ± 0.2 km) and actual distance (13.8 ± 0.9 km vs 7.7 ± 0.7 km) moved during an active period but do not differ in the percentage of their home-range area traversed in a single day (3%). Young males tended to have smaller home ranges (151 ± 45 km2) than adult males and showed a spacing pattern more similar to adult females than adult males. In common with other solitary mustelids, the spatial organization suggests a polygynous or promiscuous mating system.

Life-history variables of an atypical mustelid, the honey badger Mellivora capensis

The honey badger, or ratel, Mellivora capensis has not been well studied and data on life-history variables have previously been incomplete and contradictory. Here we present data on life-history variables that were collected from visual observations as part of the first intensive study of free-living honey badgers (25 radio-marked individuals) and we make comparisons with other similarly sized mustelids (5–25 kg). The honey badger is a non-social species and only the mother rears the young. The data do not support delayed implantation as gestation was a maximum of 50 –70 days with the unusually small litter size of one cub. The long time to independence of both male and female cubs (12 –16 months) resulted in birth intervals longer than 12 months with no distinct breeding season. Overall the honey badger appears to have a more K-selected life history compared to other species within the Mustelidae.

Pup Provisioning in the Cooperatively Breeding African Wild Dog, Lycaon pictus, is Driven by Pack Size, Social Status and Age

Division of labour, in terms of providing for offspring, in obligate cooperatively breeding mammalian species is poorly understood. To understand offspring provisioning in a cooperatively breeding canid, we analysed a long-term dataset comprising 22 African wild dog, Lycaon pictus, denning events (nine packs over nine consecutive years). We investigated the effects of sex, age class, social status, and pack size on the likelihood and frequency of regurgitating food to pups at the den. We found that the interaction of social status and pack size affected the likelihood of regurgitation. Specifically, when in a large (≤15) pack, dominant individuals were less likely to regurgitate than subordinate individuals. However, in smaller (≤ 15) packs, dominant individuals were more likely to regurgitate than subordinate individuals. We also found that the interaction of age and pack size affected the frequency of regurgitation. Specifically, in large packs, yearlings regurgitated more frequently per observation period than adults. Contrastingly, in smaller packs, adults regurgitated more frequently. Sex did not affect pup provisioning. We suggest that these contrasting patterns of helping are best explained by a strong selection pressure for individual behaviour that results in larger pack sizes in this species. When in larger packs, costs are shared as the division of labour spreads amongst individuals. In smaller packs, a division of labour requires individuals that already experience costs (such as reproduction) to be further burdened by provisioning. Overall, our results support that the need for more helpers to care for offspring contributes to the evolutionary consequence of an inverse density dependence.