Influence of Livestock and Electrified Fences on Livestock Depredation and Habitat Selection by Grizzly Bears in the Mission Valley, Montana

MS Thesis, Kari Eneas (2017-2020)

Balancing protection between livestock and carnivores has been a long-standing challenge in conservation. When encounters between carnivores and livestock or humans result in conflict or livestock depredation, the safety of both wildlife and humans are at risk. Reducing livestock depredation by grizzly bears (Ursus arctos horribilis) will be important as populations continue to recover and expand beyond public lands in the Northern Continental Divide Ecosystem. We used GPS locations from 8 female grizzly bears spanning 5 years in the Mission Valley, Montana, to evaluate the effect of livestock on habitat selection of grizzly bears. The Mission Valley is located on the Flathead Indian Reservation, where grizzly bears have been historically revered; however, modern cultural diversity complicates current management. We found a positive relationship in habitat selection for streams and wetlands by grizzly bears. We found that bears did not select for livestock, and that livestock did not have an effect on selection of streams or densities of homes or roads. Whereas electric fencing has been frequently used to protect bee apiaries from depredation by bears in North America, they have only recently been used to protect crops and livestock against grizzly bears. Maps based on our results can be used to identify how and where electric fencing efforts could be focused to reduce livestock depredation. We identified 20 sites with small livestock that had electrified fencing and 72 sites that were unfenced in 2018. We monitored 12 electric fences surrounding small livestock and recorded the presence and behaviors of grizzly bears in the Mission Valley during 2018 – 2019. No depredations occurred when livestock were inside a properly functioning electric fence, and 7 livestock depredations occurred at sites without electrified fencing. This suggested that electric fences were effective at reducing livestock depredations by grizzly bears. Though different attitudes about grizzly bears exist on the Flathead Indian Reservation, proactive and non-lethal actions can be implemented by residents to minimize future conflicts between livestock and grizzly bears. Securing small livestock, agricultural crops and livestock feed inside of an electric fence can prevent conflict in the Mission Valley.