Distribution and occupancy of wolverines on tundra, northwestern Alaska

• Published in: The Journal of Wildlife Management
• Main Authors: Poley, Lucy G., Magoun, Audrey J., Robards, Martin D., Klimstra, Ryan L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2018
• Subjects: Canis lupus; Gulo gulo; north slope; Rangifer tarandus; Tundra; Alaska
• Online Access: http://dx.doi.org/10.1002/jwmg.21439; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjwmg.21439; http://onlinelibrary.wiley.com/wol1/doi/10.1002/jwmg.21439/fullpdf

ABSTRACT Understanding wildlife distribution and habitat use is needed for effectively balancing resource development, wildlife conservation, and Alaska Native subsistence on the North Slope of Alaska, USA. This region includes the National Petroleum Reserve‐Alaska (NPR‐A), a 96,000‐km 2 remote area of largely undeveloped lands that is important for wildlife, including caribou ( Rangifer tarandus ), wolves ( Canis lupus ), and wolverines ( Gulo gulo ). We focused our study on spring distribution and occupancy of wolverines in the NPR‐A because a baseline distribution estimate is required to understand current distribution and track changes over time. We conducted aerial surveys of wolverine tracks in snow during March and April of 2014 and 2015, surveying over 84,400 km 2 using 100‐km 2 hexagonal sampling units. We used hierarchical Bayesian occupancy modeling to determine wolverine distribution and estimate probability of occupancy within each hexagon, relative to measured covariates with potential to affect either detection or occupancy. Probability of wolverine occupancy increased as well‐drained soils increased, suggesting that wolverines prefer drier areas or habitat features associated with well‐drained soils. In addition, as standard deviation of elevation increased, wolverine occupancy also increased, indicating that wolverines may prefer areas with more rugged and variable terrain. Mean elevation was not retained as a covariate in the best‐fitting model, supporting the importance of terrain ruggedness rather than elevation on wolverine distribution within the NPR‐A. Spatially, areas of highest wolverine occupancy occurred within the southern and northeastern portions of the study area, with lowest occupancy in the northern portion of the study area west of Teshekpuk Lake. Based on the spatial pattern of wolverine probability of occupancy, we proposed 4 potential wolverine management zones with varying priorities for monitoring and managing wolverine populations. © 2018 The Wildlife Society.