The unique spatial ecology of human hunters.

Human hunters are described as 'superpredators' with a unique ecology. Chronic wasting disease among cervids and African swine fever among wild boar are emerging wildlife diseases in Europe, with huge economic and cultural repercussions. Understanding hunter movements at broad scales has implications for how to control the spread of these diseases. Here we show, based on analysis of the settlement patterns and movements of hunters of reindeer (n = 9,685), red deer (n = 47,845), moose (n = 60,365) and roe deer (n = 42,530) from across Norway (2001-2017), that hunter density was more closely linked to human density than prey density and that hunters were largely migratory, aggregated with increasing regional prey densities and often used dogs. Hunter movements extended across Europe and to other continents. Our results provide extensive evidence that the broad-scale movements and residency patterns of postindustrial hunters relative to their prey differ from those of large carnivores.

Interaction effects between weather and space use on harvesting effort and patterns in red deer.

Most cervid populations in Europe and North America are managed through selective harvesting, often with age- and sex-specific quotas, with a large influence on the population growth rate. Less well understood is how prevailing weather affects harvesting selectivity and off-take indirectly through changes in individual animal and hunter behavior. The behavior and movement patterns of hunters and their prey are expected to be influenced by weather conditions. Furthermore, habitat characteristics like habitat openness are also known to affect movement patterns and harvesting vulnerability, but how much such processes affect harvest composition has not been quantified. We use harvest data from red deer (Cervus elaphus) to investigate how weather and habitat characteristics affect behavioral decisions of red deer and their hunters throughout the hunting season. More specifically, we look at how sex and age class, temperature, precipitation, moon phase, and day of week affect the probability of being harvested on farmland (open habitat), hunter effort, and the overall harvest numbers. Moon phase and day of week were the strongest predictors of hunter effort and harvest numbers, with higher effort during full moon and weekends, and higher numbers during full moon. In general, the effect of fall weather conditions and habitat characteristics on harvest effort and numbers varied through the season. Yearlings showed the highest variation in the probability of being harvested on farmland through the season, but there was no effect of sex. Our study is among the first to highlight that weather may affect harvesting patterns and off-take indirectly through animal and hunter behavior, but the interaction effects of weather and space use on hunter behavior are complicated, and seem less important than hunter preference and quotas in determining hunter selection and harvest off-take. The consideration of hunter behavior is therefore key when forming management rules for sustainable harvesting.

What determines variation in home range size across spatiotemporal scales in a large browsing herbivore?

1. Most studies of intraspecific variation in home range size have investigated only a single or a few factors and often at one specific scale. However, considering multiple spatial and temporal scales when defining a home range is important as mechanisms that affect variation in home range size may differ depending on the scale under investigation. 2. We aim to quantify the relative effect of various individual, forage and climatic determinants of variation in home range size across multiple spatiotemporal scales in a large browsing herbivore, the moose (Alces alces), living at the southern limit of its distribution in Norway. 3. Total home range size and core home range areas were estimated for daily to monthly scales in summer and winter using both local convex hull (LoCoH) and fixed kernel home range methods. Variance in home range size was analysed using linear mixed-effects models for repeated measurements. 4. Reproductive status was the most influential individual-level factor explaining variance in moose home range size, with females accompanied by a calf having smaller summer ranges across all scales. Variation in home range size was strongly correlated with spatiotemporal changes in quantity and quality of natural food resources. Home range size decreased with increasing browse density at daily scales, but the relationship changed to positive at longer temporal scales. In contrast, browse quality was consistently negatively correlated with home range size except at the monthly scale during winter when depletion of high-quality forage occurs. Local climate affected total home range size more than core areas. Temperature, precipitation and snow depth influenced home range size directly at short temporal scales. 5. The relative effects of intrinsic and extrinsic determinants of variation in home range size differed with spatiotemporal scale, providing clear evidence that home range size is scale dependent in this large browser. Insight into the behavioural responses of populations to climatic stochasticity and forage variability is essential in view of current and future climate change, especially for populations with thermoregulatory restrictions living at the southern limit of their distribution.