Research

Predator Guild Study: Population Monitoring and Behavioral Ecology

Monitoring trends in animal population sizes and distribution is an essential component of wildlife research and management. By tracking radio-collared individuals, BPCT monitors the movement lions, leopards, cheetahs, spotted hyenas and wild dogs to describe their social behavior and investigate habitat use, interactions within and between species, foraging patterns and population dynamics. Habitat and ranging studies give a unique opportunity to investigate interactions between competing carnivores.

Home ranges overlap between different carnivores species. The large home range of a wild dogs pack (Mathew's pack; in black) partially overlaps with the home ranges of three hyena clans (in red) and two collared leopards (in green).

Herbivore Population Monitoring

Prey population density and distribution affect the distribution of all large carnivores. To provide effective management of predators, reliable measures of prey populations are required. BPCT conducts both aerial and on the ground herbivore censusing twice a year (wet and dry season). A standardized method of ground surveying for herbivores has been developed by BPCT and adopted nationwide in 2007.

BioBoundary Project
Tico McNutt, PhD and Peter Apps, PhD

In the first phase of the five-year BioBoundary project funded by the Paul G. Allen Family Foundation, The Botswana Predator Conservation Trust has established an analytical chemistry laboratory, dedicated to identifying the signaling chemicals in African wild dog territorial scent marks. The aim is to identify the chemicals in the scent mark odour that are sending the territorial "No Trespassing" signal and to use them to make artificial territorial boundaries that will protect wild dog packs by keeping them within the safety of protected conservation areas. The laboratory, headed by semiochemistry specialist Dr Peter Apps, is located only 60 km from the area where the BPCT's Dr Tico McNutt has been studying wild dogs for 20 years, the first time that such a laboratory has been established so close to the study animals' natural habitat.

African Wild Dogs, like nearly all mammals, send their social messages as complex mixtures of airborne organic chemicals, called semiochemicals. Wild dog packs stake out their hunting territories with patches of soil soaked with the urine of the pack's alpha pair, and the odour of these scent marks tells neighbouring packs and itinerant dispersers "This area is occupied, no trespassing."

Over the next four years the laboratory will be cracking the territorial chemical code by searching for the components of scent marks that match the known properties of the territorial messages. The "Keep Out !" signals are persistent through time, robust to dramatic changes in temperature and humidity, present in urine but not faeces, and probably specific to African wild dogs. Once these components have been highlighted against the chemical background they will be identified, and formulated as artificial scent marks that will be tested on the free roaming wild dogs in the BPCT study population. Ultimately, refined formulations of the prototype marks will be deployed as BioBoundaries where human - predator conflict threatens the survival of wild dogs and the livelihoods of rural people.

Niche segregation by Cheetahs
Femke Broekhuis, PhD Candidate

Niche segregation by Cheetahs (Acinonyx jubatus) as a mechanism for co-existence with Lions (Panthera leo) and Spotted hyaenas (Crocuta crocuta).

The aim of the research is to gain a better understanding of the complexity of the ecological and behavioural relationships between sympatric, competing species within the predator guild. The focus will be on the mechanisms by which the cheetah (Acinonyx jubatus), a competitively weak species, can co-exist with competitively more dominant species such as spotted hyaenas (Crocuta crocuta) and lions (Panthera leo).

GPS radio-telemetry collars designed to collect fine-scale data will be used to explore the extent and patterns of behaviour which allows for their co-existence by looking at dietary overlap, daily activity and habitat selection patterns on different spatio-temporal levels for cheetahs, lions and hyaenas. Once analysed, these data will hopefully give us a better insight into the mechanism by which these competing carnivores co-exist. Since competition plays a central role in structuring species communities, it is important to take this multi-species approach if we want to develop effective conservation policies for these species.

Habitat use and segregation of carnivores
Gabriele Cozzi, PhD Candidate

Patterns of habitat use and segregation in the African wild dog Lycaon pictus, the spotted hyena Crocuta crocuta and the lion Panthera leo.

As a consequence of human induced habitat loss, competing species are forced into smaller areas, thereby increasing the frequency of negative interactions. Within African ecosystems, the highly endangered African wild dog Lycaon pictus has been shown to suffer from competition with both the spotted hyena Crocuta crocuta and the lion Panthera leo, and from direct predation by lions. Competition with and predation by these two dominant members of the carnivore guild have been proposed to be one of the main causes of the observed low densities at which the African wild dogs occur throughout its range.

With my research I aim to study (1) how these three, competing carnivore species affect each others' behaviour and ecology and (2) the mechanisms leading to their co-existence. I will analyze and compare patterns of habitat use and spatial and temporal segregation of the African wild dog, the spotted hyena and the lion. For the first time African wild dogs, spotted hyenas and lions inhabiting the same area will be fitted with highly precise GPS radio collars. Recent advances in battery and GPS radio collars technology will give me the unique opportunity to simultaneously study these three sympatric carnivores on the necessary fine spatial and temporal scale. GPS locations for the three species will be overlaid on electronic vegetation maps and prey species distribution maps.

A complete understanding of the habitat requirements for each species and how species influence each other's habitat use is an essential component of endangered species management. The results of my study will provide valuable information on habitat selection that can be used to improve conservation management practices, especially for small, protected areas where species need be actively managed. With fewer than 5, 000 individuals left in the wild, African wild dogs are on the verge of extinction. Understanding the factors that influence population dynamics is crucial to the development of conservation strategies that will ensure the survival of this species. The same strategies may be applied to the conservation of other vulnerable carnivores such as the cheetah Acinoyx jubatus.

Scent marking behavior and chemistry
Megan Parker, PhD candidate University of Montana

Unlike most other large carnivores, wild dogs do not vocalize over long distances and rely heavily on chemical signals to communicate. A fundamental requirement of these highly social animals is to defend their large territories, even when they are unable to physically patrol their borders. Chemical samples were collected from a sub-sample of collected scent marks, analyzed using gas chromatography and mass spectrometry (GC/MS) to identify compounds, and then manipulated in the field to experimentally measure reactions from a recipient pack and subsequent movements. This PhD research was the precursor to the BioBoundary Project. Data collection was done between 1998 through 2004.

Territoriality and Livestock Conflict
Matt Swarner, PhD candidate, University of California, Davis

Matt started with BPCT as a volunteer in 2001. His continued with a PhD project in 2004 on this broad effort to understand and manage healthy predator populations within the context of an expanding human population. If attacks by wild dogs on livestock occur patchily and in certain situations (e.g. where wild prey is depleted), stakeholders may be able to mitigate loss by addressing the particular conditions where conflict is high. Reducing conflict is a critical step in minimizing lethal control of wild dogs and other predators and establishing rangelands as viable landscapes for their conservation. Efforts by BPCT to meet farmers, understand conflict, educate stakeholders and suggest solutions to human wildlife conflict are ongoing.

Vocal Communication in Large Carnivores
Hugh Webster, PhD Sussex University

Hugh worked on the vocal repertoire of African wild dogs, with a particular focus on the production of very high frequency calls. The hypothesis that ultra sonic calls might provide "eavesdropper-free" communication is being investigated. Completing work from the 2005 and 2006 field seasons, playback experiments between lions (Panthera leo), spotted hyenas (Crocuta crocuta) and African wild dogs (Lycaon pictus) were carried out in 2007. These experiments were designed to investigate in greater depth the relationship between these sympatric large carnivores by measuring behavioural responses to interspecific vocalizations. Dr Webster was awarded his PhD in January 2009.