Abstract
Induced fear by predation risk can alter prey behaviour and impact the prey’s energy balance, with possible consequences on the population level. Alongside environmental changes and human disturbance, Scandinavian moose (Alces alces) face mortality risk from multiple predators; mainly wolves, which recently repopulated, and hunting, their primary cause of mortality, even within wolf territories. Additionally, moose may not be able to distinguish actual hunting risk from general human disturbance, which they likely perceive as akin to predation risk. Multiple studies have examined the population-scale influence of wolf predation and hunting on moose using telemetry yet lack a behavioural context to be able to assess possible impacts on the moose energy budget beyond alterations in movement. By analysing activity budgets of female moose in relation to relative risk values derived from moose mortality and human activity, this study attempted a qualitative estimation of possible energetic costs of hunting and predation risk. In 2020 and 2021, we equipped five female moose in south-central Scandinavia with multi-functional collars, which, for one year, recorded 20-second videos every two hours during daylight and logged hourly GPS positions. I analysed the presence-absence of four primary moose behaviours (lying, foraging, locomotion, alert), derived from video analysis using the event-logging software BORIS, in relation to estimated mortality risk from wolf predation and hunting. According to my results, female moose prioritise energy-accumulating (foraging) and preserving (lying) activities over risk-avoiding and energy-demanding activities (alert, locomotion) in all seasons (pre-hunting, hunting and winter), as any variation in mortality risk from hunting or wolf predation had a substantial effect on their activity budgets. I found only a weak response to human disturbance predictors, contrary to earlier small spatiotemporal scale studies, which tested possible effects of human disturbance with direct approaches. Future studies could combine controlled disturbance experiments and multi-functional collars with additional accelerometer-units and night-vision to get 24-hour, quantitative estimates of the energetic costs of different disturbances on a broader scale.
