Protection status, human disturbance, snow cover and trapping drive density of a declining wolverine population in the Canadian Rocky Mountains.
Mirjam Barrueto, Anne Forshner, Jesse Whittington, Anthony P Clevenger, Marco Musiani
Author Information
Mirjam Barrueto: Department of Biological Sciences, University of Calgary, 507 Campus Dr NW, Calgary, AB, T2N 4V8, Canada. mirjam.barrueto@ucalgary.ca.
Anne Forshner: Parks Canada, Banff, Yoho and Kootenay National Parks, PO Box 213, Lake Louise, AB, T0L1E0, Canada.
Jesse Whittington: Parks Canada, Banff National Park Resource Conservation, PO Box 900, Banff, AB, T1L 1K2, Canada.
Anthony P Clevenger: Western Transportation Institute, Montana State University, P.O. Box 174250, Bozeman, MT, 59717-4250, USA.
Marco Musiani: Dipartimento Scienze Biologiche Geologiche Ambientali, BiGeA, Università di Bologna, Bologna, Italy.
Protected areas are important in species conservation, but high rates of human-caused mortality outside their borders and increasing popularity for recreation can negatively affect wildlife populations. We quantified wolverine (Gulo gulo) population trends from 2011 to 2020 in > 14,000 km protected and non-protected habitat in southwestern Canada. We conducted wolverine and multi-species surveys using non-invasive DNA and remote camera-based methods. We developed Bayesian integrated models combining spatial capture-recapture data of marked and unmarked individuals with occupancy data. Wolverine density and occupancy declined by 39%, with an annual population growth rate of 0.925. Density within protected areas was 3 times higher than outside and declined between 2011 (3.6 wolverines/1000 km) and 2020 (2.1 wolverines/1000 km). Wolverine density and detection probability increased with snow cover and decreased near development. Detection probability also decreased with human recreational activity. The annual harvest rate of ≥ 13% was above the maximum sustainable rate. We conclude that humans negatively affected the population through direct mortality, sub-lethal effects and habitat impacts. Our study exemplifies the need to monitor population trends for species at risk-within and between protected areas-as steep declines can occur unnoticed if key conservation concerns are not identified and addressed.
