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2006.17(1)--81-91.pdf | Download |
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American black bears (Ursus americanus) are commonly captured for research purposes with Aldridge traps. Disadvantages of this method include the possibility of non-target species setting off traps or being captured, a lengthy installation time, the possibility of bears being captured by the toes, and hind-foot captures. Here, we describe the RL04 trap, used with rubber-padded snares and drags, designed to address these issues. The RL04 trap is built from study PVC tubing, can only be triggered by a bear in most areas, requires 20 minutes of installation time for 2 people, rarely results in toe captures due to the distance between the trigger and the snare, and eliminates hind-foot captures. This trap design captured 38 bears in 2 study areas. Every trap triggered by a previously untrapped bear resulted in a capture, and all snares tightened proximal to the metacarpal pad. Between 2001 and 2005, we trapped 304 bears using rubber-padded snares in an effort to reduce cuts and swelling often caused by bare-wire snares. These snares, tightened around bear paws with various trap designs including ground sets, produced surface cuts smaller than 1 cm in only 12 bears. Rubber-padded snares were linked to custom-designed drags and shock absorbers to reduce the risk of shoulder injuries. We provide detailed design descriptions of the RL04 trap and the restraining mechanism, which includes the snare, shock absorber, and drag.