Wolves play an integral role in maintaining the health of wildlife and ecosystems, and indirectly, livestock and public health. Recognition of this role and its ecological ramifications calls for greater respect, protection and incresed numbers of wolves in appropriate habitats across North America. Current federal and state government initiatives, backed by diverse vested interests, are poised to reduce the nation’s existing wolf population which is contrary to the directives of sound science, reason and the public interest.
State wildlife management practices directed to maximize deer numbers for recreational hunters, rural America’s virtual extermination of the wolf over the past two centuries, coupled with forest management practices and agricultural expansion indirectly providing feed for deer and the encroachment of real estate housing developments with deer-attracting gardens and vegetation in municipal parks, have had unforseen consequences associated with high White tail deer numbers; and elk in western states. Two of these unforseen consequences concern public health and potential harm to the livestock industry which a higher population of wolves across the U.S. would do much to recitify.
According to the Minnesota Dept. of Natural Resources, “After the young (fawns) are born each spring, there are between 900,000 and 1,000,000 (White tail) deer in Minnesota. The hunting season is important to keep the deer population from getting too large. Each year, Minnesota hunters harvest between 150,000 and 200,000 deer”.
Hunters seek out the healthiest deer and trophy antler- bearers in particular. A seasonal hunt eliminating almost one quarter of the deer population means starvation for wolf in deer-hunted zones at the start of winter. This probably increases their predation on livestock. Increasing deer hunting quotas to better regulate deer numbers is not a biologically appropriate response even though it is a multibillion-dollar source of revenue for states and equipment suppliers.
Wolves prey on deer year-round, taking the slower ones weakened by injury and disease, and therefore play a significant role in controlling diseases carried by deer, notably prion-causing Chronic Wasting Disease (CWD). This disease also affects mule deer, elk and moose and is now spreading across the U.S.and Canada. Wolves are probably immune. But if these prions mutate and cross the species barrier and affect livestock, especially since prions have now been found in plants consumed by deer and also in agricultural crops consumed by livestock and humans, the consequences could have devastating economic consequences for the livestock industry. This could mirror the ‘mad cow’ disease-causing prion debacle in the U.K., which lead to mass slaughter and export bans to protect consumers of cattle infected with this form of spongioform encephalopathy from acquiring the debilitating and eventually fatal brain degeneration called Creutzfeldt-Jacob disease. Dr.Christopher Johnson with the U.S. Geological Survey, Madison, WI, who found prions in crops and vegetation consumed by deer, concludes that their findings “suggest that prions are taken up by plants and that contaminated plants may represent a previously unrecognized risk of human, domestic species and wildlife exposure to CWD and scrapie agents.”
In October 2013 it was reported that cattle in Wisconsin were diagnosed with contracting insect-born deer epizootic hemorrhagic disease, a first and a warning for the livestock industry of the need to better monitor deer numbers and disease risks, especially CWD. [Deer, elk and buffalo ranchers across the country may put wildlife and livestock at risk when unwittingly keeping animals infected with CWD and other diseases communicable to ungulates wild and domestic, including Brucellosis (Bang’s disease) Johne’s disease and tuberculosis].
Organic farmers and environmentally conscious ranchers have long recognized the role of predators and other wildlife species in helping preserve healthy ecosystems around and within their lands. An ecological approach to states’ wildife management and predator control policies and practices, moving away from what amounts to wildlife farming for recreational sports hunters of deer, elk and other selected species is called for now. In the final analysis the wolf, long reviled by cattle and sheep ranchers and seen as a competitor to be exterminated by many deer hunters, may be the ultimate savior of America’s livestock industry and of healthier deer and other wildlife numbers if the prion-induced Chronic Wasting Disease and other deer diseases communicable to livestock and other species, including humans, is to be stemmed biologically through wolf predation. This means more wolves in deer and elk habitat, (and also cougars, bears and lynx).
The Centers for Disease Control have documented over 30,000 cases of tick-born Lyme disease in humans in 2012, (other estimates being as high as 300,000), this disease being harbored by rodents and deer and which wolves can also play an indirect role in helping control. These concerns underscore the need for a revolution in state and federal wildlife and natural resource management. The adoption of principles and practices that enhance biodiversity and healthy ecosystems domestic, commerical and wild, with greater protection for wolves as an integral aspect of a more enlightened and science-based approach to a better environment for all is the core principle of the One Health movement now being embraced world wide by medical, veterinary and other authorities and agencies.
The article above was written by Dr. Michael W. Fox, who is the author of more than 40 books including The Soul of the Wolf, The Wild Canids: Their Systematics, Behavioral Ecology and Evolution, and Inhumane Society: The American Way of Exploiting Animals. He serves on the Science Advisory Board of Project Coyote ~ a national non-profit organization based in Marin County, California promoting compassionate conservation and coexistence between people and wildlife through education, science, and advocacy. For more information visit: ProjectCoyote.org
1. Angers RC, Seward TS, Napier D, Green M, Hoover E, Spraker T, et al (2009). Chronic wasting disease prions in elk antler velvet. Emerg Infect Dis.May
2. J. Zhang (2012) Ref: arxiv.org/abs/1106.4628: The Nature Of The Infectious Agents: PrP Models Of Resistant Species To Prion Diseases (Dog, Rabbit And Horses) Published in Prions and Prion Diseases: New Developments (J.M. Verdier Eds.), NOVA Science Publishers, 2012, ISBN 978-1-61942-768-6, Chapter 2, pages 41-48
3. Johnson, Christopher, (2013) Uptake of Prions into Plants. In session Current Science of Chronic Wasting Disease: What Have We Learned in the Last 5 Years? The Wildlife Society Milwaukee WI Oct 2013
4. Schultz, Rob, (2013) Rare Disease reported in Wisconsin Cattle Wisconsin State Journal, Oct 3.
5. Levi, Taal, et al. Deer, predators, and the emergence of Lyme disease PNAS 2012 ; published ahead of print June 18, 2012, doi:10.1073/pnas.1204536109 www.pnas.org/cgi/content..
6. Fox, M.W., (2012)Lyme Disease, Wildlife Management and Public Health www.drfoxvet.com see also M.W. Fox (2012) Healing Animals & the Vision of One Health. Amazon.com/CreateSpace Books.