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bioRxiv · 10.1101/2021.07.06.450999

Grizzly bear toe amputation due to seasonal overlap with furbearer trapping in southeast British Columbia

Lamb, C.·Smit, L.·Vander Vennen, L.·Mowat, G.·Proctor, M.·McLellan, B.
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Abstract

Science and adaptive management form crucial components of the North American model of wildlife management. Under this model, wildlife managers are encouraged to update management approaches when new information arises whose implementation could improve the stewardship and viability of wildlife populations and the well-being of animals. Here we detail a troubling observation of several grizzly bears with amputated toes in southeast British Columbia and assemble evidence to inform management strategies to remedy the issue. During the capture of 59 grizzly bears, we noticed that four individuals (~7%) had amputated toes on one of their front feet. The wounds were all healed and linear in nature. Further opportunistic record collection revealed that similar examples of amputated toes occurred beyond our study area, and that furbearer traps were frequently responsible for toe loss. We found evidence that seasonal overlap between the active season for grizzly bears and the fall trapping seasons for small furbearers with body grip traps and for wolves with foothold traps may explain the issue. Multiple options to reduce or eliminate this issue exist, but have varying degrees of expected efficacy and require differing levels of monitoring. The most certain approach to greatly reduce the issue is to delay the start of the marten trapping season until December 1, when most bears have denned, instead of opening the season on or prior to November 1, when more than 50% of bears are still active. Additionally, innovative solutions, such as narrowing trap entrances to exclude bear feet while still allowing entrance of target furbearers, have the potential to minimize accidental capture of bears, but the effectiveness of these approaches is unknown. Experimental evidence suggested that better anchoring traps was not a viable solution. Solutions that do not involve season changes will require monitoring of efficacy and compliance to ensure success.

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Lamb, C., Smit, L., Vander Vennen, L., Mowat, G., Proctor, M., McLellan, B.. 2021-07-07. Grizzly bear toe amputation due to seasonal overlap with furbearer trapping in southeast British Columbia. https://doi.org/10.1101/2021.07.06.450999

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