Summer and fall activity patterns of radio-monitored deer (Odocoileus virginianus) emphasize hourly differences by season and sex. In the fall deer were active at dawn whereas during the summer they were active at dusk. Lower temperatures and dew points were significantly correlated with deer movement (P < 0.01) in the fall but not in the summer. There were no sex differences as to time of activity. There was more movement during the fall, most likely due to a less abundant food supply which required greater search and more trips outside protected forest areas.