Lead: Dr. Marion L. East & Dr. Sarah Benhaiem

Assistance: Dagmar Thierer, Karl Stephan & Dr. Sonja Metzger

In collaboration with Prof. Heribert Hofer

Welcome! We study individual and social dynamics principally in African carnivores. Our key long-term research focuses on spotted hyenas in the Serengeti National Park. Research began in 1987 and currently we have detailed information on more than 2500 individually known hyenas. Our interdisciplinary research applies non-invasive and minimally invasive techniques and to further this aim we have developed and verified faecal assays for spotted hyenas.

Here is an overview of our main research foci and methods:

Why focus on spotted hyenas?

This fascinating species has a set of unique traits including female social dominance, an erectile penile structure in females similar in structure to that of the male penis, high post-natal investment in terms of lactation and facultative siblicide, females that acquire a social position immediately below that held by their mother (rank ‘inheritance’) when they become adult and immigrant males that queue (stand in line) for social status. The spotted hyena is a keystone carnivore in the Serengeti ecosystem and it is both an excellent hunters and scavenger. These aspects make it an ideal model species to study key unresolved questions on a wide range of topics, including social behaviour, sexual conflict, maternal effects, host-pathogen dynamics, endocrinology, immunology and pathogen-host adaptations.

Our study population experiences extreme and unpredictable fluctuations in prey abundance throughout the year, because of the migratory movements of its main prey – wildebeest, zebras and Thompson’s gazelles – and the low abundance of resident herbivores. We discovered that spotted hyenas in the Serengeti National Park solve this problem by ‘commuting’ long distances to forage throughout the year. Individuals leave their clan territory and travel to areas up to 70 km to locate areas contain large aggregations of migratory herbivores where they feed before returning ‘home’ to their clan territory. This commuting system is ideal for testing ideas concerning the effect of prey abundance on various aspects of hyena ecology and behaviour. Furthermore, exceptionally high post-natal maternal investment in terms of lactation and rank related access to food resources make hyenas ideal for research on socially mediated effects of maternal input on offspring survival and other components of fitness.

Human activities are an important source of mortality spotted hyenas in the Serengeti National Park. Illegal setting of wire snares by bushmeat hunters is extensive along the west and northwest border of the Serengeti National Park. Hyenas in our study population are killed as ‘by-catch’ in these wire snares when they ‘commute’ in areas containing large aggregations of migratory herbivores which are also profitable locations used by illegal bushmeat hunters.

Running Projects

African wild dogs in the Ruaha ecosystem, Tanzania: demography, ecology, healths and human wildlife conflict

Currently, knowledge of the African wild dog population in the vast Ruaha ecosystem in Tanzania is limited. The aim of this project is to provide relevant knowledge for evidenced based conservation of the important population of this endangered species in Ruaha National Park. A citizen science approach is used to monitor wild dog demography which… Read More

Early-life conditions and their long-term consequences in spotted hyenas

The developmental period is a particularly sensitive window during which the phenotypic effects of the environment are particularly marked. This means that the conditions experienced during development can have both immediate and  delayed effects on life history traits and fitness. Very little is known about these effects in free-ranging populations. My research will use long-term… Read More

Epigenetic stability and plasticity of social environmental effects

Social status significantly affects Darwinian fitness by altering health, life history, and physiological trade-offs. Because social status is usually stable throughout life and is a behaviourally transmitted trait, social inequalities persist within and across generations. Even so, the molecular mechanisms underlying these social effects are poorly understood. We hypothesize that DNA-methylation is a main epigenetic… Read More

Fitness consequences and determinants of parasite infections in a wild social carnivore, the spotted hyena

Assessing both infection and the associated immune responses in free-ranging wildlife is challenging, as is the assessment of the consequences of infection on components of Darwinian fitness throughout the life-span of an individual. Our research aims to investigate the effect of the infection load of energetically costly intestinal parasites on host immune function and assess… Read More

Intrinsic and extrinsic determinants of parasite infections in spotted hyenas in the Serengeti National Park

Currently little is known about the factors determining individual heterogeneity in parasite infections in unmanaged wild mammal populations, including the gastrointestinal community of most wildlife species. In particular, the eukaryotic proportion of the biome, the eukaryome, remains largely unknown, and little is known about the fitness consequences which parasite infections impose on their hosts. In… Read More

Investigation of the diet, activity pattern and habitat use by golden jackals and silver-backed jackals in the Serengeti Ecosystem, Tanzania’

The main objective of this study is to enhance the understanding of the diet, activity pattern and habitat use of the golden and silver-backed jackal in the Serengeti Ecosystem. The research is focused on both diurnal and nocturnal behaviour of jackals in both the dry and wet seasons. The project is expected to provide new… Read More