Ramifying effects of the risk of predation on African multi-predator, multiprey large-mammal assemblages and the conservation implications
Impacts of predators on prey populations are incurred not only through mortality inflicted, but also from how the risk of mortality affects the behaviour, spatial distribution and resource access of potential prey species. This risk is governed by exposure to predators and vulnerability following encounters. Behavioural responses to reduce risks have ramifying consequences for habitat […]
Factors Affecting Group Size and Vigilance Behaviour of Maasai Giraffe (Giraffa camelopardalis tippelskirchi) on the Serengeti-Ngorongoro Ecosystem, Tanzania
This study investigated the factors affecting different group sizes of Maasai giraffe (Giraffa camelopardalis tippelskirchi) in the Serengeti-Ngorongoro ecosystem. The study was motivated to test the following hypotheses: 1) in a given group, the sex ratio of males to females with calves is related to group size; 2) group size affects vigilance behaviour; 3) illegal […]
Sex differences in giraffe feeding ecology: Energetic and social constraints
Sex ratios of giraffe groups differ in different habitats, with open vegetation having female‐biased groups, and tall, thick vegetation having male‐biased groups. On a ranch in south‐central Kenya, we quantified habitat differences of male and female giraffe groups and showed that the preference for open habitats by female groups was limited to groups with young. […]
Scene From Above: Retinal Ganglion Cell Topography and Spatial Resolving Power in the Giraffe (Giraffa camelopardalis)
The giraffe (Giraffa camelopardalis) is a browser that uses its extensible tongue to selectively collect leaves during foraging. As the tallest extant terrestrial mammal, its elevated head height provides panoramic surveillance of the environment. These aspects of the giraffe’s ecology and phenotype suggest that vision is of prime importance. Using Nissl-stained retinal wholemounts and stereological […]
Social influences on vigilance behaviour in giraffes, Giraffa camelopardalis
Vigilance in ungulates is considered to have a predominantly antipredator function, with the frequency and duration of scans per individual decreasing with increasing group size. Social influences on vigilance scans have been overlooked in studies on ungulates, although studies in primates and birds show that conspecific scans are important determinants of vigilance behaviour. We investigated […]
Sexual segregation by Masai giraffes at two spatial scales
In this paper alternative explanations for observed patterns of sexual segregation by giraffes are examined at two spatial scales: within-habitats and within-landscape. Habitats are defined as recognizable plant associations and the landscape as the collection of all available habitat types. The study was conducted in Mikumi National Park, Tanzania. At the within-landscape level, all sex […]
Factors affecting group size and vigilance behaviour of Maasai Giraffe (Giraffa Camelopardalis Tippelskirchi) in the Serengeti Ngorongoro Ecosystem, Tanzania
This study investigates factors affecting group sizes of Maasai giraffe (Giraffa camelopardalis tippelskirchi) in the Serengeti-Ngorongoro ecosystem, northern Tanzania. Various studies on giraffes have been conducted in the past, but none has investigated factors affecting giraffes’ group size and vigilance behavior in this vast ecosystem. As a result, I was motivated to investigate the following […]