Main aspects of the conservation of larger mammals remain unanswered because the factors which favour survival, extinction and the ability of regeneration are often unknown. These factors can only be determined with the profound knowledge of the behavioural and evolutionary ecology of the species. Social organization, life history strategies, food availability, enemies, parasites and pathogens influence the frequency of reproduction, the success of raising offspring and the rate of mortality in a population. With increasing, often anthropogenic forms of stress (i.e. disturbances, noise, pollution, habitat changes), activity rhythms and space use of individuals change too, which often determine the access to resources resp. the possibility of contact with competitors, enemies, parasites and pathogens.