Killing wolves to protect cattle may backfire

A new study raises questions about how to handle livestock conflicts.

 

In two decades of studying large carnivores, nature has never failed to surprise Rob Wielgus. For example, he and his student found in 2013 that cougar hunting does not reduce complaints about people running into cougars, or livestock attacks. Harvesting cougars actually increased complaints the following year. That research led to changes in how Washington manages the big cats; last year the state stopped using heavy cougar hunting to reduce conflicts.

This week, Wielgus, director of Washington State Universitys Large Carnivore Conservation Lab, released his newest study with equally surprising results. “I analyzed it like 50 times, with different statisticians and layers and layers of peer review because the results are kind of astounding,” he says. The new paper challenges assumptions about how state wildlife agencies deal with problem wolves. It turns out that killing wolves that kill livestock may backfire in the long term. According to the study, lethal removal may actually increase the odds that wolves eat more cattle or sheep the following year.

Overall, wolves are doing fine in the Northern Rockies, compared to their brush with extinction in the 1970s. Their population has dipped slightly since its peak in 2011 to roughly 1,700 wolves, but biologists say it’s secure.

People have long assumed that fewer wolves lead to fewer depredations on sheep or cattle. And wildlife managers often say that lethal removal can be a salve for vitriol toward wolves, by providing a short-term solution for the harmed livestock producers, and by showing that states are actively managing the animals. It’s part of the reason some states allow wolf hunting, and why Washington, Montana, Idaho and Wyoming all lethally remove wolves that harm livestock. In 2013 the later three states killed 202 wolves for control purposes, or 8 percent of the population in all four states.

But when Wielgus and his coauthor looked at 25 years of data on lethal wolf control and livestock depredations from Idaho, Wyoming, and Montana they found that killing one wolf increases the odds of sheep depredation by 4 percent the following year. For cattle, it increased the odds by 5 to 6 percent. 

This pattern holds until 25 percent of the wolf population is removed. That’s because wolf populations in the states studied grow at a 25 percent rate. So once the lethal removals exceed the population’s growth rate, wolves begin to decline, and so do depredations. But that’s not a sustainable solution for the wolves, or for people who don’t want to see them on the endangered species list.

These flagged fences called fladry are one nonlethal technique that livestock producers are using to deter wolves. Image courtesy of Oregon Department of Fish and Wildlife.

It’s important to note that this study has found a correlation between wolf removal and livestock depredation over a large region, but it hasn’t established the exact reason for the patterns. To learn more about why lethal removal of wolves doesn’t appear to protect livestock, Wielgus now needs to drill down to individual packs.

Wielgus suspects the answer may be found in wolf social dynamics. The animals may compensate for losing part of their pack by increasing reproduction and thus, the need to hunt for those new pups. Or wolves may become less efficient hunters in smaller groups and turn to dining on livestock. “I think the take home point is that social behavior and social systems of these large carnivores, pack dynamics, territory, all of that is a very important element to how wolves interact with their environment,” says John Pierce, chief wildlife scientist for the Washington Department of Fish and Wildlife. “As we move forward in wolf management we should carefully be studying that and don’t assume a linear relationship (between wolf removal and depredation).”

Pierce thinks the study is too preliminary to change wolf management in the near future. But his agency is funding Wielgus to research proactive, non-lethal wolf management such as having cowboys called range riders monitoring for trouble, and using special fencing, or lights and sounds, to deter wolves. Wielgus is comparing the effectiveness of those techniques to lethal methods, and also mapping where livestock are at the greatest risk of wolf attack.

That work is still in its early stages, but Washington is starting to see good results with proactive non-lethal methods, says Pierce. Ideally, learning more about those techniques will help prevent events like what unfolded in northeastern Washington in August. The Huckleberry Pack became habituated to feeding on sheep, and after non-lethal wolf deterrents failed, a sharpshooter took out the alpha female (not the wolf they were hoping to eliminate) at the request of Washington’s wildlife department.

Wielgus hopes that his studies will help wildlife managers reevaluate practices that may be based on long-standing assumptions. “Science progresses,” he says, “and eventually we’ll get it right.”

Sarah Jane Keller is a correspondent for High Country News. She writes from Bozeman, Montana and tweets @sjanekeller. Homepage image of grey wolf being released into Yellowstone by Barry O'Neill, courtesy National Park Service,

High Country News Classifieds
  • FOR SALE
    Yellowstone Llamas Successful Yellowstone NP concession Flexible packages
  • DIRECTOR OF DEVELOPMENT & MARKETING
    Grand Staircase Escalante Partners is seeking a full-time Director of Development & Marketing. This is a senior position responsible for the development of all marketing...
  • LEGAL DIRECTOR
    The Legal Director will work closely with the Executive Director in cultivating a renewed vision at NMELC that integrates diversity, equity, and justice. Black, Indigenous,...
  • VICE PRESIDENT, LANDSCAPE CONSERVATION
    The Vice President for Landscape Conservation leads Defenders' work to promote landscape-scale wildlife conservation, focusing on four program areas: federal public lands management; private lands...
  • NOVA SCOTIA OCEAN FRONT
    Camp or Build on 2+ acres in Guysborough. FSBO. $36,000 US firm. Laurie's phone: 585-226-2993 EST.
  • COMMUNITY FORESTER
    The Clearwater Resource Council located in Seeley Lake, Montana is seeking a full-time community forester with experience in both fuels mitigation and landscape restoration. Resumes...
  • GUNNISON BASIN ROUNDTABLE
    The Gunnison Basin Roundtable is currently accepting letters of interest for ten elected seats. Five of the elected members must have relevant experience in the...
  • PCTA TRAIL CREW TECHNICAL ADVISORS IN WASHINGTON'S NORTH CASCADES
    Seasonal Positions: June 17th to September 16th (14 weeks) - 3 positions to be filled The mission of the Pacific Crest Trail Association is to...
  • WE'RE LOOKING FOR LEADERS!
    As we celebrate 50 years of great Western journalism, High Country News is looking for a few new board members to help set a course...
  • MEMBERSHIP DIRECTOR
    Job Announcement Job Title: Membership Director Supervisor: Executive Director Salary: Up to $65,000/year DOE Benefits: Generous benefits package — health insurance, Simple IRA and unlimited...
  • UTAH PUBLIC LANDS MANAGER
    Who we are: Since 1985, the Grand Canyon Trust has been a leading voice in regional conservation on the Colorado Plateau. From protecting the Grand...
  • EXECUTIVE DIRECTOR
    Executive Director Walker Basin Conservancy Reno & Yerington, NV Background The Walker Basin Conservancy (Conservancy) leads the effort to restore and maintain Walker Lake while...
  • WIND RIVER WRITERS AND PHOTOGRAPHERS RETREAT BY THE NATIONAL BIGHORN SHEEP CENTER
    Enhance your writing or photography skills with world-class instructors in the beautiful Wind River Mountains. All skill levels welcome. Continuing education credits available.
  • EARTH CRUISER FX FOR SALE
    Overland Vehicle for travel on or off road. Fully self contained. Less than 41,000 miles. Recently fully serviced Located in Redmond, OR $215'000.
  • ENVIRONMENTAL GEOPHYSICS
    identifies suspect buried trash, tanks, drums &/or utilities and conducts custom-designed subsurface investigations that support post-damage litigation.
  • EXECUTIVE DIRECTOR
    They [Northern Plains] confound the common view that ordinary people are powerless in the face of industry. - Billings Gazette editorial The venerable Northern Plains...
  • SMALL FARM AT BASE OF MOUNT SHASTA, CALIF.
    Certified organic fruit/berry/veggie/flower farm. Small home, 2 barns (one has an apartment), and more. Approx. two acres just in the City limits. Famously pure air...
  • TAOS HORNO ADVENTURES
    A Multicultural Culinary Memoir Informed by History and Horticulture. Richard and Annette Rubin. At nighthawkpress.com/titles and Amazon.
  • LAND & CABIN ON CO/ UT LINE
    18 ac w/small solar ready cabin. Off grid, no well. Great RV location. Surrounded by state wildlife area and nat'l parks.
  • CANYONLANDS FIELD INSTITUTE
    Field seminars for adults in natural and human history of the Colorado Plateau with lodge, river trip and base camp options. Small groups, guest experts.