| Summary: | The study of predatory behaviour is essential for understanding the interactions that may affect the behaviour and population dynamics of the species involved and consequent cascading ecosystem effects. In the case of large carnivores feeding on large ungulate prey, predation is strongly impacted by humans who alter the habitat of both predators and their prey, control population sizes, and compete with large carnivores for the same prey species. The objectives of this thesis were to 1) establish a robust method to estimate kill rates of wolves (Canis lupus); 2) estimate kill rates during both summer and winter; 3) relate kill rates to prey availability in winter (functional response) and to the energetic requirements of the wolf packs; and 4) to study the impact of roads on predatory and other behaviour of wolves. To meet these objectives, the Scandinavian Wolf Research Project (SKANDULV) fitted wolves with Global Positioning System (GPS) collars and searched for kill remains on clusters of GPS-positions during defined time periods in winter and summer. Winter prey densities of cervids were assessed by spring counts of faecal pellet groups. High variation in the spatio-temporal movement pattern of wolves in relation to kill sites made it difficult to predictably identify kill sites along the wolf trajectory without fieldwork. Consequently, field personnel checked all clusters, and in addition some single positions, to obtain robust estimates of kill rate. Human disturbance at kill sites may be one possible reason for the high variation in the handling of kills, with a relatively short handling time associated with kills located in areas with a high potential for human disturbance. During summer, wolves preferred to be at intermediate distances to roads while handling prey. This was probably the result of a trade-off between avoidance of human presence and the preference for roads while traveling. In most wolf territories, moose (Alces alces) was the pre-dominant prey species during both summer and winter. Kill ...
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