Effectiveness of Lethal, Directed Wolf-Depredation Control in Minnesota

Authors

Elizabeth Harper, University of Minnesota
William J. Paul, United States Department of Agriculture, Animal and Plant Health Inspection Service of Wildlife Services
L. David Mech, USGS Northern Prairie Wildlife Research CenterFollow
Sanford Weisberg, University of Minnesota, MinneapolisFollow

Date of this Version

2008

Comments

Published in JOURNAL OF WILDLIFE MANAGEMENT 72(3):778–784; 2008.

Abstract

Wolf (Canis lupus) depredations on livestock in Minnesota, USA, are an economic problem for many livestock producers, and depredating wolves are lethally controlled. We sought to determine the effectiveness of lethal control through the analysis of data from 923 government-verified wolf depredations from 1979 to 1998. We analyzed the data by 1) assessing the correlations between the number of wolves killed in response to depredations with number of depredations the following year at state and local levels, and 2) the time to the next depredation. No analysis indicated that trapping wolves substantially reduced the following year’s depredations at state or local levels. However, more specific analyses indicated that in certain situations, killing wolves was more effective than no action (i.e., not trapping). For example, trapping and killing adult males decreased the re-depredation risk. At sheep farms, killing wolves was generally effective. Attempting to trap, regardless of the results, seemed more effective at reducing depredations than not trapping, suggesting that mere human activity near depredation sites might deter future depredations.