I am interested in general ecology, and in particular in predator-prey interactions and carnivore ecology and conservation. For 25 years I worked at the Mammal Research Institute PAS in Białowieża, Poland, where I studied the community of carnivores and raptors. With a group of colleagues, we conducted radiotracking studies of wolves, lynx, and several other species. We were also working on population genetics of wolves and we designed a network of ecological corridors for Poland. In 2010, I moved to Venezuela where I have been studying jaguar population ecology with camera trapping and spatial capture-recapture models, human-jaguar conflicts, and jaguar reproduction strategies. Also, I have been modelling jaguar distribution and extirpation rates, spatial variation in population density and population size, and relative impacts of hunting and retaliatory killing on jaguar populations.