Nutrient Content in Relation to Food Preferred by Mountain Hare

Nutrient content of hare browse was analyzed. Samples were taken from 10 species in five habitat types. Analyses were made on crude protein, crude fat, sugar, ash, crude fiber, Ca, P, K, Na, and Mg. There was little variation within plant species occupying different kinds of habitats. Large differences were found between species. Choice between birch (Betula alba) and blueberry (Vaccinium myrtillus) by mountain hares (Lepus timidus) was well correlated with crude protein and phosphorus content. J. WILDL. MANAGE. 38(4):875-879 Differences in the nutritional status of browse are found between species, between plants of the same species, and even within plants (Bailey 1967a, Garcia-Moya and McKell 1970). Site exposure to sunlight may cause different food values within an apparently homogeneous habitat; there are likewise seasonal variations in nutritional content of many species (Bailey 1967b, Bobek et al. 1973, Short et al. 1966, Tew 1970). Grouse, hares, and rabbits have shown preferences for food species with a high content of nitrogen, phosphorus, and sugar (Miller 1968, Moss 1968, Radwan and Campbell 1967). North American deer also prefer certain plant species and can select plants and parts thereof on the basis of nutritional quality (Klein 1970). However, in a study done in Scotland, mountain hares showed no selection for heather (Calluna vulgaris) on the basis of its nitrogen or phosphorus content (Hewson 1973). In an earlier work, Lindlof et al. (1974) presented a diet-list for the mountain hare. Hare food was sampled for the present nutrient analysis according to this list. Our purpose was to look for differences between plant species and habitats, and to determine whether these differences were correlated with food preference. MATERIAL AND METHODS The material was collected during February 1972 in the northern part of the Grimsi Research Area, Sweden, 15025'E, 59040'N. Plant species taken for analysis had been utilized by hares in nine test areas representing five habitats (Table 1). The list of collected species gives a rough description of plant communities on these areas. Shrub density and hare feeding intensity approximately follow the alphabetic order of these areas, with fewest shrubs and lowest browsing intensity in Area A. Browse species are ranked according to degree of utilization by hares with birch highest and bog myrtle (Myrica gale) lowest. Browsing frequency was measured during hare-track counts along line transects. Tracks crossing transects were followed 25 m in each direction. One note was made for browse species utilized irrespective of the amount consumed (Table 2). To get representative samples within areas for nutrient analyses, twigs of 10 cm length were cut from bushes exposed to sunlight as equally as possible. For all 1The study was supported by grants from the Swedish National Environment Protection Board and Stiftelsen Olle Engkvist, byggmdistare. J. Wildl. Manage. 38 (4):1974 875 This content downloaded from 157.55. 39.207 on Thu, 20 Oct 2016 04:13:06 UTC All use subject to http://about.jstor. org/terms 876 NUTRIENT CONTENT AND HARE BROWSE CHOICE * Lindlbf et al. Table 1. Browse species and test areas. The areas are lichen-pine forests (A, B), bogs (C, D), mixed coniferous forests (E, F), clear-cuttings (G, H), and birch-grown pasture (I). + indicates area where sample was taken for analysis. (+) area sampled, but with no browsing on the species.