title: Acorn selection by the wood mouse Apodemus sylvaticus: a semi-controlled experiment in a Mediterranean environment.
abstract: Fruits are highly important food resources for mammals in Mediterranean Europe, and due to the dominance of oaks (Quercus sp.), acorns are among those used by a vast array of species, including rodents. The metabolic yield of acorn intake may determine a selection pattern: preference for fat, carbohydrate, and consequently energy-rich fruits; or avoidance of fruits containing high concentrations of secondary chemical compounds (e.g., tannic acid). We studied the acorn feeding selection pattern of wood mice (Apodemus sylvaticus) inhabiting a mixed oak woodland, southwest Portugal, using an experiment conducted in an open-air enclosure. We tested which variables associated with the wood mouse (e.g., sex) and acorns (e.g., size and nutrient content) from three oak species (holm Q. rotundifolia, Portuguese Q. faginea and cork Q. suber oak) could be constraining acorn consumption. Our results indicate that wood mice are selecting acorns of the most common oak species (Q. suber), probably due to their previous familiarization with the fruit due to its dominance in the ecosystem but probably also because its chemical characteristics (sugar contents). Rodent gender and acorn morphology (width) are also influential, with females more prone to consume acorns with smaller width, probably due to handling limitation. This selective behaviour may have consequences for dispersion and natural regeneration of the different oak species.
authors.affiliation: 1 Universidade de Lisboa, Centro de Biologia Ambiental, Faculdade de Ciências de Lisboa, Ed. C2, Campo Grande, Lisboa 1749-016, Portugal.
authors.forename: Luís Miguel
authors.initials: LM
authors.lastname: Rosalino
authors.forename: Filomena
authors.initials: F
authors.lastname: Nóbrega
authors.forename: Margarida
authors.initials: M
authors.lastname: Santos-Reis
authors.forename: Generosa
authors.initials: G
authors.lastname: Teixeira
authors.forename: Rui
authors.initials: R
authors.lastname: Rebelo
mesh_terms: D000818:Animals; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D005518:Food Preferences / Q000502:physiology*; D016015:Logistic Models; D008297:Male; D051189:Murinae / Q000502:physiology*; D029963:Quercus; D012639:Seeds; D013045:Species Specificity