title: The European Hare (Lepus europaeus): A Picky Herbivore Searching for Plant Parts Rich in Fat.
abstract: European hares of both sexes rely on fat reserves, particularly during the reproduc-tive season. Therefore, hares should select dietary plants rich in fat and energy. However, hares also require essential polyunsaturated fatty acids (PUFA) such as linoleic acid (LA) and alpha-linolenic acid (ALA) to reproduce and survive. Although hares are able to absorb PUFA selectively in their gastrointestinal tract, it is unknown whether this mechanism is sufficient to guarantee PUFA supply. Thus, diet selection may involve a trade-off between a preference for energy versus a preference for crucial nutrients, namely PUFA. We compared plant and nutrient availability and use by hares in an arable landscape in Austria over three years. We found that European hares selected their diet for high energy content (crude fat and crude protein), and avoided crude fibre. There was no evidence of a preference for plants rich in LA and ALA. We conclude that fat is the limiting resource for this herbivorous mammal, whereas levels of LA and ALA in forage are sufficiently high to meet daily requirements, especially since their uptake is enhanced by physiological mechanisms. Animals selected several plant taxa all year round, and preferences did not simply correlate with crude fat content. Hence, European hares might not only select for plant taxa rich in fat, but also for high-fat parts of preferred plant taxa. As hares preferred weeds/grasses and various crop types while avoiding cereals, we suggest that promoting heterogeneous habitats with high crop diversity and set-asides may help stop the decline of European hares throughout Europe.
authors.affiliation: Department of Integrative Biology and Biodiversity Research, Institute of Wildlife Biology and Game Management, University of Natural Resources and Life Sciences, Vienna, Vienna, Austria.
authors.forename: Stéphanie C
authors.initials: SC
authors.lastname: Schai-Braun
authors.affiliation: Division of Animal Welfare, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Reichlin
authors.affiliation: Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Vienna, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Ruf
authors.affiliation: Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Vienna, Austria.
authors.forename: Erich
authors.initials: E
authors.lastname: Klansek
authors.affiliation: Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Vienna, Austria.
authors.forename: Frieda
authors.initials: F
authors.lastname: Tataruch
authors.affiliation: Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Vienna, Austria.
authors.forename: Walter
authors.initials: W
authors.lastname: Arnold
authors.affiliation: Department of Integrative Biology and Biodiversity Research, Institute of Wildlife Biology and Game Management, University of Natural Resources and Life Sciences, Vienna, Vienna, Austria.
authors.forename: Klaus
authors.initials: K
authors.lastname: Hackländer
mesh_terms: D000818:Animals; D004041:Dietary Fats / Q000008:administration & dosage*; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage*; D034621:Hares / Q000502:physiology*; D060434:Herbivory; D018514:Plant Structures / Q000737:chemistry*
chemical_list: D004041:Dietary Fats; D005231:Fatty Acids, Unsaturated