• Version
• Download 11
• File Size 407.30 KB
• Create Date 1 April 2009
• Download

Wildlife researchers and managers have been using Aldrich foot snares to capture American black bears (Ursus americanus) and grizzly bears (U arctos) for decades. Recently, failures have been reported in snare cable assemblies, resulting in escapes of both black and grizzly bears. We tested different configurations of snare cable and hardware using a hydraulic pull machine. Snare foot loops constructed with compression sleeves or Crosby® clips torqued to 20.3 newton-meters (N-m) consistently exceeded minimum strength requirements for use on large bears (> 16.8 kilonewton [kN]). In our tests, anchor sections of snares using compression sleeves and 0.794 cm swivels never failed below 30 kN. It is important to use robust, manufacturer-rated hardware and precise methodology when building snare cables to achieve consistent holding strength. The use of substandard components and improper torquing of clamps can result in failure of the snare endangering both bears and capture personnel.