Various survey methods are used to monitor and manage ungulate populations. The choice of optimal method depends on estimation accuracy, management objective and financial constraints. Here we compare estimates produced by four different methods for estimating population size, i.e. aerial counts, hunter observations, pellet group counts and cohort analysis. A Swedish moose Alces alces population was studied during 1973-2005 in the Grimso¨Wildlife Research Area (135 km 2 ). The highest correlation was found between cohort analysis and aerial counts (r=0.69, P<0.05), and the hunter observations and the aerial counts (r=0.76, P<0.10). The different methods produced relatively consistent trends in population estimates over years. Pellet group counts prior to 1997 were not significantly correlated with the other methods, probably due to unrepresentative spatial sampling. A comparison of the aerial and pellet group counts in 2002 and 2006, showed that the average defecation rate was estimated at approximately 14 pellet groups per day per moose. Our results show the importance of having representative spatial sampling in pellet group surveys and indicate that hunter observations can be a useful tool for estimating long-term population trends even in moderately sized areas.

Scale dependence is a fundamentally important topic in ecology because it determines whether results can be generalized over different spatial scales. We studied the relationship between forage consumption by moose ( Alces alces (L., 1758)) and forage availability across six nested spatial scales in south-central Sweden. By using multiple regression, we concluded that the amount of available forage was the best single variable explaining absolute consumption, irrespectively of scale. Forage species diversity, site productivity, and moose density were also important for predicting forage consumption, but their effects differed across the different spatial scales. A multiple regression including forage availability, moose density, site productivity, and forage diversity explained between 31% and 49% of the variation in forage consumption. The importance of a moose index as an explanatory variable decreased with increasing spatial scale, whereas the importance of site productivity increased. According to model selection based on Akaike's information criterion, the same model was ranked highest at the four smallest spatial scales, whereas the top-ranked models at the two largest spatial scales differed. Furthermore, the relationship between consumption and forage availability changed from underutilization at small scales to proportional use at the home range level. Thus, for a comprehensive understanding of moose browsing in relation to food resources, we conclude that a multi-scale approach is necessary.

The brown hare (Lepus europaeus) expanded its Swedish distribution since the 1980s northwards and locally to new areas within its former range. Of 115 brown hare populations within the former range reported in a hunter enquiry, those established after 1980 were situated higher above the sea level than older ones and higher than neighbouring (<50 km) older populations. Reports on increased use of forest habitats by brown hares were equally frequent among recent and older populations, suggesting a process promoted solely by less harsh winters. Supposed hare hybrids were more often reported from hunting grounds with recent brown hare establishment, i.e. where the species expands in time and in space. In a 27-year dataset on brown hare observations, the recent increased use of forest habitats was supported in that maximum distances to agricultural land for brown hare sightings were higher in mild winters, whereas the proportions of the annual observations made during winter were lower. In 40-year bag records from two Swedish counties, the dynamics of the mountain hare (Lepus timidus) responded positively to snow parameters, whereas brown hares responded negatively. We suggest that the state of mountain hare populations primarily depends on winter conditions and predation pressure, whereas possible effects of hybridization are unclear. If winter conditions remain as in the last 15 years, mountain hare numbers are not likely to increase in southern Sweden, whereas the brown hare may expand even further. In either case, hybrids will occur in sympatric areas in frequencies probably related to the density of the respective true species.

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