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The range size of adult female mountain hares (Lepus timidus L.) and European rabbits (Oryctolagus cuniculus L.), occupying a landscape composed of moorland, young poorest and upland pasture, were studied by radio-telemetry. The factors that affect range size of the two species were identified and interpreted with regard to their respective feeding strategies; mountain hares are summer grazers that browse in winter whereas rabbits eat grasses throughout the year. Individual mountain hares were classified as 'moorland', 'forest' or'pasture' hares, and individual rabbits were classified as 'forest', 'pasture' or 'mixtures rabbits according to the frequency with which they used each habitat. Home-range size of both species was highly variable with a mean area (and standard deviation) of 22.2 ha (SD = 18.5) for hares and 6.3 ha (SD = 3.9) for rabbits. Home-range size of mountain hares varied according to habitat and season. There was a negative correlation between home-range size and the available green biomass of grass. This suggests that the large home ranges of 'moorland' hares during the breeding and post-breeding seasons may have been a consequence of low food availability. Home-range size of rabbits also varied according to habitat and season, but was not clearly associated with food availability, feeding strategy or social behaviour. In the early years following planting, extensive afforestation of upland moorlands is unlikely to affect mountain hare and rabbit populations if an abundant ground flora is available. Individuals of both species may even remain entirely within the plantation using very small home-ranges. However, single age plantations would have to be restructured to increase the age diversity and hence the availability of suitable habitats for long-term maintenance of viable populations of mountain hares.

We tested resistance to the hare (Lepus timidus) of one-year-old seedlings of ten birch (Betula) species showing different life history strategics. Also, we tested the effect of fertilization and shading on the resistance and growth of eight species, including several geographic origins of some. Resistance varied substantially and consistently among the ten birch species. both in field and in cafeteria experiments. Three species exhibited high resistance (B. ermanii. B. platyphylla, and B. resinifera), and six high susceptibility (B. alleghaniensis, B. grossa, B. maximowicziana. B. papyrifera, B. pubescens and B. schmidtii). B. pendula exhibited substantial variation in resistance among individuals and origins. Inherently fast-growing species showed a strong response to fertilization. Growth rate was not related to resistance/susceptibility at the species level. Fertilization significantly lowered the apparent resistance of two of the three resistant species (B. resinifera was invariant), but did not change the susceptible species. Shading substantially decreased seedling mass at high, but not at low nutrient levels, and generally had only a minor effect on resistance. The resistance of B. pendula and B. platyphylla seedlings from different geographic origins varied significantly, but growth and resistance of these seedlings were not related. There was no significant difference in resistance between the easternmost of the western Siberian and the Finnish origins of B. pendula, nor was there any east-west (55°-78°E longitude) clinal trend in its resistance. The resistance of progeny from fast growing Finnish B. pendula families (plus trees) was similar to that of randomly selected forest origins from Finland and western Siberia. Resistance and growth were not related in this comparison either. These results emphasize the great genetic and phenotypic variabiiity both within and among birch species but lend little support for the hypothesis predicting a trade-off between growth and hare defense investments in one-year-old birch scedlings.

Mountain hares (Lepus timidus L.) are summer grazers that switch to browse in winter, while rabbits (Oryctolagus cuniculus L.) eat mostly grasses throughout the year. These different feeding strategies may underlie seasonal patterns of habitat selection by the two species. In this study the habitat utilization by adult female mountain hares and adult female rabbits was studied by radio-tracking in a habitat composed of open moorland, upland pasture and young forestry plantation with an abundant ground flora. The selection of feeding habitats by populations of both species was assessed by faecal counts within the same landscape. Despite the common perception that mountain hares in Britain are associated with moorland, open moorland was avoided by the radio-tracked adult female mountain hares relative to its availability. Throughout the year, the radio-tracked hares preferred the forest and pasture habitats relative to availability. Only seven of the 20 hares radio-tracked were ever located on the moorland, which would suggest that the presence of moorland is not a prerequisite for the presence of mountain hares. Radio-tracked adult female rabbits utilized the habitats in proportion to their availability. Counts of faecal pellets indicated that utilization of forestry plantations by both species declined as a spruce forest matures although hare populations persist in mature pine plantations with an abundant ground flora. Mountain hares appear to be more adaptable than rabbits in their use of the habitats in this study, a behavioural tactic underpinned by their flexible feeding strategy. Rabbit populations would persist in areas following afforestation, especially where upland pastures are in close proximity to woodland and mountain hares would be capable of exploiting many of the new habitats that are created, at least in the early years of forest development.

The probability that an individual plant will be attacked by a herbivore depends not only on the characteristics of the individual plant, but also on the quality and abundance of its neighbours. However, plants have been reported to receive protection from herbivory both when associated with plants of higher and lower palatability (the attractant-decoy and repellent-plant hypotheses, respectively), and there are no mechanistic explanation for these different outcomes of plant spatial association. We used patch-use theory (marginal-value theorem) to predict under which circumstances we should expect plants to gain protection from herbivory due to association with other plants

Salt blocks placed afield by Swedish hunters for wild ungulates also are used by mountain hares (Lepus timidus). However, little is known about the seasonal patterns of salt use by hares, a fundamental consideration regarding the potential benefit of this mineral appetite. Thus, we monitored the use of salt- block (NaCl) stations by mountain hares at the Grimso Wildlife Research Station, Riddarhyttan, Sweden from April 1988 to june 1989. Use of the stations peaked between April and july, declined to a low in january, and then rose again to the April-july peak. We suggest that this use reflects an appetite for sodium (Na) that may result from the ingestion of plant secondary compounds, a seasonal excess of dietary potassium, and/or the nutrient demands of growth and reproduction

In two field experiments the feeding preference of voles (Microtus agrestis and Clethrionomys glareolus) and hares (Lepus timidus), offered winter dormant shoots/branches of three deciduous tree species, were determined and related to nutritional quality and concentration of phenolics. Both the voles and the hares consumed more rowan (Sorbus aucuparia)/aspen (Populus tremula) (vole and hare experiment, respectively) than birch in the patches containing birch (Betula pubescens) together with rowan/aspen and slightly but not significantly more birch than alder (Alnus incana) in the birch/alder patches. Further-more, the overall concumption in both patch types was highest in rowan/aspen (vole and hare experiment, respectively) and lowest in alder, with birch being intermediate

(1) The home range of mountain hares in north-east Scotland was studied by radiotracking between 1982 and 1986. (2) Home ranges (minimum convex polygon) were large; 113 ha for males, 89 ha for females. Using 90% of radio-fixes reduced the intersexual difference in size because males moved around the periphery of their range in the breeding season. Some of these movements may lead to the establishment of new centres of activity. (3) Home ranges comprised day resting places in long heather and discrete night feeding areas downhill. (4) Heavier, presumably dominant, males had smaller home ranges than lighter males. (5) Male mountain hares moved to day resting places higher on the hill in July, females in September, in both cases after the end of reproductive activity. (6) Hares formed larger groups after the breeding season, up to thirty hares in January and February. (7) Male hares flushed at greater distances than females, which occupied better cover. (8) Home ranges needed to provide shelter and food during severe weather and extensive snow-lie. They were larger than those of brown hares in a more sheltered environment with a diversity of food within a short distance.

(1) The method described enables rapid polishing of sections of bone tissue to permit age determination from annual growth lines. (2) A sample of mandibles from twenty mountain hares of known age from N.E. Scotland provided a calibration for the method. (3) The growth lines probably form during the autumn, in October and November, and hence the method is less accurate if applied then. This loss of accuracy applies generally to age determinations using growth lines and has often been overlooked. (4) In the population of mountain hare females studied in 1984, there was a scarcity of females born in 1980.

(1) On heather moorland in Shetland, mountain hares (Lepus timidus L.) were more numerous than in other Scottish islands, the west and north-west of Scotland and the north of England. (2) In winter, hares were widely spaced on heather-dominated vegetation. In spring, they commonly occurred in dyads < 10 m apart. (3) Available shelter from weather and predators was less good in Shetland than in north-eastern Scotland, where mountain hares are most abundant. (4) Exposure limits the growth of heather in Shetland, and extensive burning, leading to the replacement of heather by Molinia and Trichophorum heaths, as practised in west and north-west Scotland, does not occur. (5) The large extent of heather (the main food of mountain hares) in Shetland compared with many parts of mainland Scotland probably accounts for the relative abundance of hares, and is likely to be more important than the absence of predators upon adult hares.

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.

Les arbres broutes anterieurement par Alces alces sont generalement plus infestes par les insectes que les non-broutes; ces arbres broutes ont des feuilles plus larges contenant plus d'azote et de chlorophylle. On analyse les reponses defensives de la plante au broutage notamment par les lievres

Neutral fat and protein reserves were measured in three species of grouse, cottontail rabbits, snowshoe hares and European hares collected during the mid to late winter period in their natural habitats. Neutral fat levels were measured in arctic hares from the Canadian high arctic during late summer. Sharp-tailed grouse, spruce grouse and ruffed grouse contained, respectively, 2.2, 2.3 and 1.0 g of fat per 100 g fat-free body weight, regardless of sex, year or location. Cottontail rabbits, arctic hares, snowshoe hares and European hares had, respectively, 4.1, 2.5, 2.3-4.1 and 6.9 g of fat per 100 g fat-free body weight. The low values for fat and protein reserves are similar to those reported for other grouse and leporid species in different parts of North America and Scandinavia. Collectively they indicate that species in both taxa have little metabolic resistance to winter fasting and must feed regularly to maintain energy balance. Grouse, hares and rabbits in winter habitats share similar energetic tactics of acquiring small energy reserves, feeding regularly for short periods and emphasize energy conservation rather than energy acquisition. A theoretical model relates the size of energy reserves in these species to the probability and duration of fasts due to severe winter weather, the changing quality of diets, and the probability of predation while amassing reserves prior to winter and using them during winter.

The population densities of mountain hares Lepus timidus L. were compared with those of red grouse Lagopus 1. scoticus (Lath.), within and between study areas on heather Calluna vulgaris (L.) Hull moors in north-east Scotland. Mean densities varied greatly between different areas, in both hares and grouse. They were higher on the areas where the underlying rock was richer and the heather was more nutritious. The amplitude of population fluctuations differed greatly between different areas in both species. The amplitude was generally bigger in hares than grouse. Fluctuations of the two species were not in phase within areas. Within each species, population fluctuations were not in phase on different areas.

Numerous observations on lungworms in wild hares (Lepus timidus, L. europaeus) have been made at various places in Europe during the past century and a half, but it has been only within the last ten years that parasitological examinations of Varying hares (Lepus americanus) have revealed the presence of related metastrongyloids in this hemisphere. During the past four years one of us (Goble) has had the opportunity of autopsying a number of Varying hares from the eastern United States and Canada. It is the purpose of this paper to record observations on the incidence and identity of the lungworms in these animals. Boughton (1932) found lungworms in 25 of 30 (83 per cent) Varying hares in southern Manitoba. He described these nematodes and named them Synthetocaulus leporis. Green and Shillinger (1935a) reported lungworms in 6 of 75 (8 per cent) hares (L. americanus phaeonotus) in Minnesota. This survey was conducted by J. F. Bell during the months of April through July inclusive, and the worms were designated as Synthetocaulus leporis. In collections made in Minnesota and Wisconsin during October and November of the same year Green and Shillinger (1935b) noted lung lesions in 25 of 40 (62 per cent) hares. These lesions were described and attributed to the presence of lungworms which were called Synthelocaulus cuniculi. MacLulich (1937) stated that lungworms in hares (L. a. americanus) in Ontario "were only occasionally found and then in small numbers." Of the animals which were examined in the course of the present study 87 were Lepus americanus virginianus from New York and 44 were L. a. struthopus from New Brunswick. They were collected during the months of November through March inclusive. The New York specimens came from three different localities in the Adirondack region.