Date of this Version
Specialized radio transmitters were developed for use in monitoring large mammal trap and snare activity. Prototype devices were manufactured by 4 wildlife telemetry companies based on specifications we developed in consultation with electronic engineering personnel. Power outputs from individual transmitters ranged from 10 to 100 milliwatts (mw). Range testing in the gently rolling terrain of northeastern Colorado indicated that ground-tracking distances with truck-mounted dual beam antennas exceeded 40 km. Field tests were conducted using transmitters with traps and foot snares set for coyotes (Canis latrans) in California, black bears (Ursus americanus) in Oregon, and mountain lions (Felis concolor) in Arizona. Our results indicated that electronic monitoring could be a practical approach to reducing field operating costs and check times for devices set in remote areas. Other applications for the technology, such as use with cage traps in suburban areas, also appear feasible.