Free-ranging dogs

The influence of free-ranging dogs on the native wildlife populations in the Mara North Conservancy, Masai Mara


Student: Nicolai Elmo Jensen

Program: MSc., Aarhus University

Supervisor: Professor Trine Bilde, Department of Bioscience, Genetics, Ecology and Evolution, Aarhus University.

External supervisor: Jesper Stagegaard, CEO Ree Park and Chairman of the Board, Karen Blixen Camp Ltd. Kenya.

Period: October 2014

Master's Thesis:


As the very first part of a long-term dog project, Nicolai Elmo Jensen (MSc.), started the project as his master’s thesis. 

Dogs in the Masai culture are used for guarding and protecting livestock from wild predators and thereby reducing the human-wildlife conflicts that are inevitable in areas where humans and wildlife coexists. However dogs have been proven to have deleterious effects on wildlife with regard to pathogen transmission, predation, disturbance etc. In the private Mara North Conservancy (abbreviated MNC), bordering the world famous Masai Mara National Reserve, impacts of dogs had never been investigated. Obtaining knowledge on the impact of dogs on wildlife is essential for setting up the future conservation and management schemes to improve the future conservation and management of this unique area of Masai Mara.


The aim of this paper is to clarify some of the current potential threats and impacts of the increasing dog population in the MNC. Based on studies linking dogs with pathogen transmission to wildlife, I examined whether dogs in MNC were exposed to pathogens and thereby posing a potential transmission risk to the native wildlife. To gain information on the prevalence of canine distemper virus, canine parvovirus, sarcoptic and intestinal parasites in dogs, a serological survey of stray dogs (free-ranging and ownerless) was conducted.

When disturbed, larger mammals often tend to escape over long distances and are likely to be displaced from their home range, stressed physiologically, and experiences the negative effects of the escape for longer durations. I investigated whether the number of dogs had a disturbing effect on the abundance of wildlife, in an observational survey conducted along transects. It was expected that a negative correlation occurred between number of dogs and wildlife abundance. Additionally, to assess the potential for interactions between free-ranging dogs and wildlife, dogs were GPS collared to gain information on free-ranging behavior and home range size.

In order to contribute to and improve the management of HWC in a responsible and sustainable manner, an ethnographic questionnaire survey among the local Masai community was conducted. The questionnaire survey was also used to gain information on interactions between dogs and wildlife.



Increasing abundance of free-ranging domestic dogs (Canis familiaris) along boundaries of protected wildlife reserves is of growing concern to conservationists in the rural areas of Kenya, as well as the rest of the world. Several studies have shown that dogs have multiple negative impacts on native wildlife populations, including being vectors and reservoirs of numerous of transmittable pathogens, predators, and competitors. This study has examined some of the potential threats free-ranging dogs pose to the native wildlife in the Mara North Conservancy, along the northeastern border of Masai Mara National Reserve. In the present study, the current dog population within the conservancy was estimated to c. 2500 dogs, where the majority is owned by settlers, though free-roaming. Of 28 dogs sampled, 25% and 67,8% were tested positive for antibodies against canine distemper virus and canine parvovirus, respectively. Intestinal parasites were found in 3 out of 31 samples. Prevalence for sarcoptic mange was not detected. In transect observation studies, no significant effect of the number of dogs on the abundance of wildlife was observed, although there was a tendency for lower numbers of wildlife observed when more dogs were available. The average home range size of eight GPS collared dogs was 2.26 km2 (range 0.10 - 8.11 km2). Distance from manyattas (Masai settlements), revealed a significant positive correlation with wildlife abundance, which suggest that human settlement and activity has a negative effect on wildlife. Dogs in the MNC had the potential to interact with the native wildlife at several levels, such as pathogen vectors, agents of disturbance, predators and competitors. To minimize the dog-wildlife interactions and human-wildlife conflicts, a multipronged approach is recommended. A combination of vaccination, lethal control, restriction of free-ranging behavior and implementation of a trained guarding dog is suggested. The empirical data presented in this paper calls for more studies to make more informed decisions for conservation and management of the MNC.