- African wild dog dispersal and demography
The African wild dog (Lycaon pictus) is Africa’s most endangered large carnivore and is listed as endangered in the IUCN Red List. The species was formerly distributed throughout sub-Sahara Africa but today it has disappeared from most of its former range. Less than 6’000 free-ranging individuals survive in the wild, and the species has been given very high conservation priority. One major threat to the survival of the species is the loss and fragmentation of suitable habitats due to expanding human population. As a result, wild dogs are forced to live in isolated small subpopulations, which are particularly
- Conservation biology of amphibians and reptiles in Switzerland
Supervised by Benedikt Schmidt
Human activity is the cause of the ongoing biodiversity crisis. Our goal is to do research on the conservation biology of amphibians and reptiles because we would like to understand how conservation problems can be solved and thereby population declines halted or even reversed. In doing so, we would like to contribute to evidence-based conservation.
- Hierarchical spatiotemporal modelling of distribution and abundance of Swiss breeding birds
Spatiotemporal patterns in distribution and abundance are a fundamental theme in ecology and applied fields such as biodiversity monitoring and conservation. However, two common problems are (i) limited spatial or temporal extent and (ii) interpretational challenges due to the complex observation process underlying most ecological field data. This may jeopardise inferences about distribution and population dynamics unless the main features of the observation process are well understood, so that their biasing effects can be removed.
- Individual strategies, group dynamics and population regulation in cooperative breeders
Many species live in socially and spatially structured populations, and the behavioural, evolutionary, and demographic aspects of sociality have been the focus of much theoretical and empirical research. One major shortcoming of the empirical work, due mainly to practical considerations, has been its focus on already-established social groups (either in captivity or in the wild) and its omission of complexity in between-group processes, such as dispersal and new group formation. Natal dispersal of individuals, immigration into existing groups, and new group formation are latent but crucial aspects of
- Linking behavioural, physiological and demographic responses to climate change
There is an increasing body of evidence highlighting ecological alterations induced by climate change across the globe. Recently, Henri Weimerskirch and his colleagues showed that the wandering albatross (Diomedea exulans), a wide-ranging Sub-Antarctic seabird responded behaviourally, physiologically and demographically to changing wind patterns. This bird, which takes advantage of winds to reduce the flying cost, benefited from stronger winds and could cover more distance during foraging trips. Consequently, individuals increased in mass and had a higher reproductive success. Taking into consideration the potential changes in the environment is crucial to efficiently manage wild populations. Changes in the
- Predicting population responses to environmental change
A major goal in biodiversity conservation is to predict responses of biological populations to environmental change. To achieve this goal, we must identify early warning signals of the demographic changes that underlie sudden population declines or explosions. Some studies have achieved phenomenological prediction of sudden changes, but recent advances that link trait-based information with demography hint that a mechanistic understanding is within reach. We are developing a predictive framework by investigating how wildlife populations respond demographically, ecologically and evolutionarily to environmental change, and identifying the demographic and phenotypic statistics
- Project GIRAFFE
The gentle, iconic giraffe indicates the health of African savanna ecosystems, home to some of the most spectacular displays of wildlife in the world. But savanna ecosystems are in serious trouble. Habitat loss, illegal hunting, and disease are decimating savanna wildlife. Giraffe numbers have declined drastically to fewer than 100,000 across the African continent.
Since 2011, Project GIRAFFE: GIRAffe Facing Fragmentation Effects has been monitoring births, deaths, and movements of more than 2,100 individual giraffes in an area over 1,500 square kilometers in the Tarangire Ecosystem of northern Tanzania. We use a special computer program that recognizes each giraffe’s unique fur pattern from
- Resurrecting population responses to past environmental changes from lake sediments
In this project, we investigate life-history responses of a freshwater rotifer, Brachionus calyciflorus, in retrospect. This is possible because brachionid rotifers produce dormant stages, so-called resting eggs, some of which remain viable in lake sediments for decades.
During the last century, Lake Orta – a deep, subalpine lake in northern Italy – was severely affected by industrial pollution. In 1926, a newly established textile factory began to discharge copper- and ammonium-sulphate contaminated sewage into the lake. The following acidification of the lake resulted in a dramatic decrease in rotifer diversity and an accumulation of resting eggs in the sediments. From