Real-time video recording of food selection by captive white-tailed deer

Abstract

Knowledge of animal behavior and resource selection is most accurate when direct observations of animals are made. It is impractical, if not impossible, however, to directly and efficiently observe free-ranging animals for extended periods of time without affecting their behavior. To help address these difficulties, we designed a miniature animal-mounted wireless video camera system that remotely records a portion of the sighting field of white-tailed deer (Odocoileus virginianus). The system consisted of a miniaturized charge-coupled-device (CCD) video camera, a miniaturized UHF transmitter (channel 30 or 42), a light-activated on-off relay circuit, protective plastic housing, a combination VCR/TV, a UHF TV antenna on a 9.1-m mast, and 12 9V lithium-ion DC batteries on a leather neck collar. The real-time color video image was transmitted up to 500 m and recorded on VHS tape. Using this system, we videotaped daytime observations of white-tailed deer food choices for up to 2 weeks. We assessed food choices from 70 hours of video footage from 1 antlered deer recorded during fall 2002 to demonstrate the utility of the technique. Our video system allowed us to monitor detailed food choices without the logistical difficulties present in direct observational studies. This tool could prove useful in studying detailed behavioral observations of captive animals; future development of electronic components could offer applications to free-ranging deer.