Elk forage and risk tradeoffs during the fall archery season

Jesse DeVoe; Kelly Proffitt; Michael S. Mitchell; Craig Jourdonnais; Kristin J. Barker

doi:10.1002/jwmg.21638

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Elk forage and risk tradeoffs during the fall archery season

Jesse DeVoe·Kelly Proffitt·Michael S. Mitchell·Craig Jourdonnais·Kristin J. Barker

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Abstract

During late summer and fall, elk ( Cervus canadensis ) need access to adequate nutrition to support physiological requirements for reproduction and overwinter survival. The archery hunting season often occurs during this period and can affect distributions of elk as they seek areas that minimize perceived harvest risk. Areas that confer lower harvest risk may provide relatively low‐value nutrition, resulting in a potential tradeoff between minimizing risk and accessing adequate forage. We used radio‐collar data collected from female elk during late summer and fall (Aug–Oct) and estimated resource selection models to evaluate the extent of this potential risk‐nutrition tradeoff. To evaluate if elk exposed to a greater hunting risk altered selection for forage resources, we assessed the relationship between individuals’ selection coefficients for forage and the proportion of their late‐summer‐fall home range accessible to hunters (our metric of hunting risk). Our results indicate that during the archery season, elk with higher‐risk home ranges selected more strongly for areas farther from motorized routes than elk with lower‐risk home ranges. Regardless of the level of risk, however, elk maintained or increased selection for areas with higher forage quality, suggesting that elk did not compromise access to nutritional resources during the archery season. Elk with higher‐risk home ranges were also exposed to the poorest nutrition and increased their selection for areas with higher forage quality more strongly than elk with lower‐risk home ranges during the hunting season. Elk with lower‐risk home ranges had access to the highest nutrition, which may be due to the availability of concentrated sources of high‐quality forage from irrigated agricultural areas on private lands that restricted hunter access. Resource agencies interested in encouraging elk to remain on public lands during the hunting seasons might consider closing motorized travel during the archery season to increase security on public lands, limiting hunter pressure on public lands, improving forage quality on public lands, and working with private land owners to enhance hunter accessibility and restrict elk access to high‐quality forage resources.

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Journal of Wildlife Management Article

Source-reported bounding extent: 46.01985337287631° to 46.92963428624288° latitude; -114.488525390625° to -113.54644775390625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Jesse DeVoe, Kelly Proffitt, Michael S. Mitchell, Craig Jourdonnais, Kristin J. Barker. 2019-02-05. Elk forage and risk tradeoffs during the fall archery season. https://doi.org/10.1002/jwmg.21638

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