VARIABLE ACORN CROPS - RESPONSES OF WHITE-TAILED DEER AND OTHER MAST CONSUMERS

We examined movements and behavior of female white-tailed deer (Odocoi leus virginianus) relative to the acorn mast-fall from 1986 through 19 89 in a mature deciduous forest in Front Royal, Virginia. Ten white-ta iled deer with radiotransmitters increased their home range to incorpo rate acorn-producing areas during mast-fall. Consumption of acorns by deer constituted ca. 50% of foraging time during peak mast-fall; avera ge consumption rate was 0.75 acorns/min searching. Although the number of acorns eaten by deer was correlated with mast-fall, a prolonged ti me was spent searching for acorns after mast-fall. Deer consumed 70% o f marked acorns placed out during mast-fall, while medium-sized animal s (e.g., Tamias striatus, Sciurus niger, Sciurus carolinensis) consume d 61% of acorns placed out later in autumn. We hypothesize that high d ensities of deer may limit populations of more mast-dependent species, particularly at low acorn-crop densities.