An infrared video camera system for monitoring diurnal and nocturnal raptors

A black and white, circuit-board video camera system with night vision was designed to monitor Mexican Spotted Owl (Strix occidentalis lucida) behavio r. A 0.5-Lux infrared camera equipped with a 3.3 mm 3 m in total darkness w ith the aid of six infrared light-emitting diodes (LEDs). To extend nightti me visibility at selected sites to approximately 6 m, we constructed a supp lemental EI-LED infrared light source. Industrial-grade video recorders pro vided up to 24-hr coverage per VIIS rape. Cameras averaged 6.9 m from nests (range 3.0-10.3 m). Mean camera installation time was 42 min (range 28-71 min). Between 25 April-3 July 1996, approximately 820 hr of video effort (7 6 hr for equipment assembly, 14 hr for camera placement 230 hr for maintain ing tapes and batteries, and 500 hr for subsequent video analysis) provided 2655 hr of usable video coverage (149 tapes) at 20 nest sites, a return ra tio of nearly 3,2:1 hr of coverage for each hour invested. Comparable detai l, quality, or quantity of behavioral data would nut have been possible thr ough direct observation. This video system could have a wide application in other raptor behavior studies, especially for determining the effects of h uman activities.