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Livestock grazing is one of the primary uses of sagebrush rangelands in western North America; therefore, an understanding of the ecological implications of grazing on habitat quality for sagebrush-dependent wildlife is needed to help land managers balance multiple objectives for land use. We studied effects of cattle grazing on components of habitat for an uncommon sagebrush habitat specialist, the pygmy rabbit (Brachylagus idahoensis), which has been petitioned for endangered or threatened status in the USA. We evaluated multiple components of habitat before and after grazing in replicated control and treatment plots in a mesic, high-elevation sagebrush-steppe environment in south-western Montana, USA. We predicted that grazing would decrease the biomass of herbaceous forage, alter security cover, and increase rate of collapse of rabbit burrows, and we expected that these effects would be more pronounced during summer than spring. As expected, cattle grazing reduced the biomass of perennial grasses available to pygmy rabbits after grazing that occurred during either spring or summer, and the biomass of forbs after spring grazing. In contrast, grazing did not markedly influence the functional properties of vegetation related to predation risk or the integrity of rabbit burrow systems. In the context of the stocking rate of the allotments in our study (7.3 acres/Animal Unit Month, 2.95 ha/Animal Unit Month), annual cattle grazing did not seem to markedly change habitat for pygmy rabbits in our study area; however, longer-term and higher intensity grazing might result in more pronounced habitat changes. Understanding the ecological implications of cattle grazing on habitat quality for pygmy rabbits and other sagebrush-dependent wildlife can guide conservation strategies for these species on sagebrush rangelands managed under multiple-use policies.

Context Measures of intake and digestibility from captive feeding experiments are often used to evaluate the nutritional value of plant species to herbivores; however, there is question about how well plant-quality rankings from these trials predict foraging patterns of free-ranging animals. Studies addressing the alignment of results from feeding trials and herbivory in the field using captive and free-roaming conspecifics are needed. Aims Our goal was to compare the feeding patterns of snowshoe hares in captive intake and digestion trials with those of free-living conspecifics in the species’ south-western range. Methods We conducted in vivo intake and digestion trials using captive hares to determine quality and consumption levels of the predominant conifer species in our study system. In the field, we quantified browsing intensity and over-winter depletion patterns of these conifers. We then compared voluntary intake and nutritional quality measured in captivity to consumption in the field. Key results Digestible energy (DE, kJ g–1) of conifers ranged from 11.0 (Pinus contorta) to 13.8 (Pseudotsuga menziesii) among six conifers, and digestible protein (DP, g protein per 100 g feed) from 1.2 (Thuja plicata) to 2.7 (P. contorta). During digestion trials, single-species intake was correlated with the content of digestible protein (DP) and digestible energy (DE). Hares maintained energy balance when fed two single-species diets (Pinus contorta, Pseudotsuga menziesii) and a mixed-species diet. Conifer species on which hares were able to maintain body mass (Pinus contorta, Picea engelmannii, Pseudotsuga menziesii) also tended to be the most heavily exploited by free-living hares. DP content of browse species predicted both browsing intensity and overwinter depletion of conifer species. Conclusions Voluntary intake and nutritional quality of browse, especially DP, successfully predicted foraging patterns of free-ranging conspecifics. Implications Intake and digestion trials can be a useful tool for better understanding patterns of herbivory in the field, and winter habitat quality for populations in this region is likely to be influenced by access to the most energy- and protein-rich conifers.