Abstract

Poaching is an important limiting factor for many large carnivore populations worldwide and the effect that legal culling has on poaching rate on wolf (Canis lupus) is debated. We used data linked to population monitoring and research to analyze rate and risk of disappearance without known cause for territorial pair-living wolves (n = 444) in Sweden 2000/01-2016/17. Known mortalities included legal kills (n = 103), natural causes (n = 23), traffic (n = 8) and verified poaching (n = 20) but most (n = 189) wolves disappeared without known cause. Careful evaluation of alternative causes supported the assumption that poaching was the most likely reason for the majority of these disappearances. Disappearance rate was 0.14 for the entire study period, and increased from 0.09 in 2000/01-2009/10 to 0.21 in 2010/11-2016/17, while a Kaplan-Meier analysis on a sub-sample of radio collared wolves (n = 77) gave an average annual poaching rate of 0.12 for the entire study period and 0.10 and 0.18 for the corresponding two sub-periods. Factors affecting disappearance rate were modeled using logistic regression and Cox proportional hazards regression. Population size had a strong positive effect on disappearance rate in both models, whereas legal culling rate had a negative effect, significant only in the Cox model. The combined effect of legal culling rate and disappearance rate during the latter part of our study period has halted population growth. Our results contribute to an increased understanding of two vital drivers predicted to affect poaching rate: population size and legal culling.

Keywords

Canis lupus; Carnivore management; Mortality; Poaching; Wildlife crime; Wolves; Legal culling; Inbreeding

Published in

Biological Conservation
2020, Volume: 243, article number: 108456
Publisher: ELSEVIER SCI LTD

SLU Authors

• Liberg, Olof

  • Department of Ecology, Swedish University of Agricultural Sciences
    

• Åkesson, Mikael

  • Department of Ecology, Swedish University of Agricultural Sciences
    

• Andren, Henrik

  • Department of Ecology, Swedish University of Agricultural Sciences
    

• Wikenros, Camilla

  • Department of Ecology, Swedish University of Agricultural Sciences
    

• Sand, Håkan

  • Department of Ecology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Ecology
Fish and Wildlife Management


Publication identifier

DOI: https://doi.org/10.1016/j.biocon.2020.108456

Permanent link to this page (URI)

https://res.slu.se/id/publ/105616