Variability in Maternal Behavior by Dall's Sheep: Environmental Tracking or Adaptive Strategy?

摘要: Effects of environmental variation and timing births on patterns nursing weaning behaviors were examined in Dall's sheep ( Ovis dalli ) central Alaska. Indices plant productivity, growing season, quality diet (crude protein feces) indicated that later phenology resulted a shorter season 1989. Timing parturition was ca. 2 weeks less sychronous 1989 than 1988. Females responded to this delay births, forage availability quality, by lambs for greater total time following parturition, reducing spent more rapidly Maternal females exhibited associated with often during early lactation 1989, when delayed. Patterns maternal care did not correspond indices diet, suggesting these differences result from tracking. At far northern latitudes, where the period which rear young is limited, plasticity investment compensate conditions births. This variability likely represents an adaptive strategy important even highly predictable environments only slight or occasional annual variation.