Influence of Habitat on Acorn Selection by Peromyscus leucopus

Abstract

Acorn selection by white-footed mice (Peromyscus leucopus) was tested with mice from four different habitats and acorns from six species of oaks (Quercus). Three mice captured in white-oak (subgenus Lepidobalanus) forests in northwestern Arkansas selected acorns from the white-oak group (post [Q. stellata] and white [Q. alba] oaks) over those from the red-oak (subgenus Erthrobalanus) group (pin [Q. palustris], willow [Q. phellos], and black [Q. velutina] oaks). These mice were able to subsist for >2 months on a diet of only acorns, provided that acorns from post oaks were available. These mice developed signs of tannin poisoning when maintained on acorns only from the red-oak group. Eleven mice captured in white-oak forests in eastern Kansas also consumed more acorns from the white-oak (post, bur [Q. macrocarpa], and chinquapin [Q. muehlenbergii] oaks) than from the red-oak group (black, northern red [Q. rubra], and pin oaks). However, seven mice captured in red-oak group forest in eastern Kansas consumed more acorns from the red-oak group than from the white-oak group and showed no signs of tannin poisoning. Five mice captured in habitats without oaks consumed equal amounts of acorns from the two subgenera. These results suggest that exposure to acorns may determine acorn selection by P. leucopus independent of fat, protein, or tannin content of the acorns. Acorn selection may be labile, as seven mice captured in white-oak forests in eastern Kansas consumed equal amounts of bur and black oak acorns after being given only red-oak acorns for 9 days.