Oecologia (1993) 95:226-233 Oecologia 9 Springer-Verlag 1993 Winter ecology of nonmigratory Alpine red deer Karoline Schmidt Institut ftir Wildbiologie und Jagdwirtschaft, Universitfit fiir Bodenkultur, A-1190 Wien, Peter Jordan Strasse 76, Austria Received : 23 December 1992 / Accepted: 13 April 1993 Abstract. In winter, red deer (Cervus elaphus hip- pelaphus) that are not receiving supplementary feeding emphasize and rely on energy-saving strategies. In severe winters with deep snow, they select a home-range habitat - windblown alpine pastures above the timberline - that meets the requirements of this strategy: a much lower sinking depth and good forage availability are due to patchy snow distribution, while the open area provides higher radiation, permits group formation and thus so- ciobiological wellbeing. The energy costs of thermo- regulation are minimized by selecting slopes with south to south-west exposures, seeking thermal shelter from strong winds, while high flight distances and horizontal flight routes reduce the energy costs of fleeing. In years with little winter snowfall non-supplemented red deer prefer the greater security of forested habitats in lower areas and obtain higher food intake from slightly more nutritious meadows in the valley bottom. The food- supplemented herd has much more constant and predict- able habitat use, combining an energy-saving strategy - choosing alpine pastures as low-cost winter home range - with high energy income at the feeding station. Key words: Cervus elaphus -Winter ecology- Behaviour- al adaptations - Habitat use - Winter feeding Nonmigratory alpine red deer populations (Cervus elaphus hippelaphus) may winter in high alpine habitats without supplementary feeding. Little is known of the winter ecology of these populations. Till now, research on winter ecology of alpine red deer has mainly con- centrated on the effects of supplementary feeding (e.g. in- creased antler size, forest damages). Hunters justify the use of feeding stations by the fact that alpine red deer were once known to migrate seasonally between high- elevation alpine summer ranges and low-elevation winter ranges (e.g. Bfitzler 1972; Georgii 1980; Hofman and Kirsten 1982; Raesfeld and Reulecke 1988). These migrations no longer take place. Human land use occu- pied the original red deer habitats (riverine lowland forests) and artificial feeding retains populations in al- pine ranges. Red deer have become year-round in- habitants of alpine regions. Most studies consider that nutritional needs are the main determinants of migration (Atzler 1984; Morgantini et al. 1989; Ruhle and Looser 1991). The lack of adequate and accessible forage in alpine habitats in winter is thought to be compensated by artificial feeding, which in alpine regions is regarded as a prerequisite for the survival of huntable stocks. But these feeding stations strongly influence natural habitat choice in red deer. Therefore one main objective of this research study was to examine winter habitat choice in a non-supplemented herd and what adaptations to win- ter severity these red deer have developed. This paper compares wintering strategies of alpine red deer populations with and without winter food supple- mentation, wintering in the same area. Material and methods Study area Situated in the eastern part of the Austrian Alps, in the Lower Tauern mountain range (47~ 14~ the study area (Fig. 1) includes the west and east slopes of a valley running north to south, with an altitudinal range from 900 m above sea level (a.s.1.) to the highest elevation of the alpine meadows at 2260 m a.s.1. Boreal vegetation, consisting nearly exclusivelyof spruce (Picea abies) and larch (Larix decidua), reaches 1701~1750m a.s.1. The timberline is bordered in some areas by alder and dwarf pine. The dominant rock is mica slate. The vegetation of the alpine brown soil includes Carex curvula, Nardus stricta, Deschampsia cespitosa, Calluna vulgaris, Loiseleuriaprocumbens, Vaccinium spp. ( V. myrtillus, V. vitis-idae, V. uliginosum ) , Festuca spp., and various lichens (Klug et al. 1989). Mountain meadows above the timberline cover extensive, moderatly inclined areas which are extensively grazed by cattle in summer and are potential red deer home range in winter. Study methods Two herds, with and without supplementary winter feeding, were compared. The winter ranges of the two herds were clearly