Evaluation of a Modified Neck Snare to Live-Capture Coyotes

Pruss, S.D., N.L. Cool, R.J. Hudson and A.R. Gaboury. 2002. Evaluation of a modified neck snare to live-capture coyotes. Wildlife Society bulletin. 30(2):508-516.

Many researchers opt for the most humane and safe techniques when obtaining live animals for study. A variety of devices are employed in the trapping of coyotes (Canis latrans), one option being the neck snare. Since all trapping methods have their dangers, researchers in the article "Evaluation of a modified neck snare to live-capture coyotes," are motivated to improve trap safety to decrease mortality rates.

The modified neck snare consisted of a supporting wire, swivel, locking neck snare and a diazepam tab sedative. The thick, supporting anchor wire (firmly attached to a tree or log) was secured to a snare swivel. Connected to the swivel was the locking snare, which was comprised of a Cam-LocTM. The lock was set to 27cm so that coyotes could be caught safely while reducing the capture of non-subject animals (i.e. elk, moose, deer, and bison). The diazepam tab, also attached to the swivel, consisted of 40mg of crushed diazepam between two strips of cotton. Consumed at the time of capture, this sedative was important to live-captures by decreasing aggression thus lowering incident of injury (lacerations or bruising) and death due to stress or fatal injuries.

Research of coyotes occurred in a 194-km2 area of Elk Island National Park (EINP), of Alberta, Canada. 51 coyotes were captured between 15 November-1 April over a period of 9,379 trap nights and 7,421 trap days. Researchers took care in assembling the snares so that any traces of human scent were masked. The traps were then set up along game trails avoiding any exposed or hazardous sites. Every 12-24 hours they were checked to reduce capture time, further reducing stress and injury. Once captured, the coyote was restrained and the immobilizing anesthetic, Telazol, was administered to keep them stationary. The animal was kept warm during the cleaning and stitching of injuries, recording of weight, fitting of eartags and radiocollars, blood collection and injection of antibiotics and an antiparasitic agent. The coyote was then left in an isolated location and kept warm by blankets until the effects of the Telazol wore off.

At the close of the study, 19 injuries and only one death occurred out of the