DENVER–In mid-February the Colorado Division of Parks and Wildlife (CDPW) reported the presence of a pack of six wolves in northwestern Colorado. Genetic testing on feces samples found near a scavenged elk carcass in Moffat County confirmed that at least three females and one male wolf are living in Colorado.
The feces testing also confirmed that three of the six fecal samples are carrying the potentially-deadly hyatid disease.
Colorado has been anticipating the natural migration of wolves into the state since at least May, 2005, when CDPW’s Wolf Management Working Group’s 2004 recommendations were adopted by the Colorado Parks and Wildlife Commission. The Commission is a citizen board, appointed by the governor, which sets regulations and policies for the wildlife agency.
The plan goals include “acceptance of a wolf presence in Colorado” contingent on being able to deal with potential or actual conflicts with humans, livestock, big game and habitat impacts as well as close management and monitoring of wolves and livestock depredation and both compensation and deterrence funding for ranchers.
Now a new threat to wildlife, livestock and even humans has emerged.
Hyatid disease, or Echinococcus granulosus is a parasitic tapeworm found in canids such as dogs, wolves, coyotes and foxes. This parasite requires two hosts during its lifecycle. The tapeworms, about 3-5 mm long, live in the small intestines of canids and the eggs are passed in feces. The eggs are tiny and quite hardy, remaining viable for up to a year.
The intermediate hosts are ungulates, which includes elk, deer, moose, sheep and cattle. These hosts pick up the eggs while browsing in areas where host feces are found.
Infections cause wasting, loss of weight and other health issues in host animals, including livestock. The cycle completes when predators and scavengers eat the viscera of infected animals.
Domestic animals including cattle, sheep, dogs and cats can be infected, and can pass the infected eggs to humans.
While humans are not a natural host they can be infected by ingesting the parasite’s eggs. Usually this happens after handling contaminated soil, canid feces or fur, through breathing infected dust stirred up by human activity and ingestion of contaminated foods such as green vegetables and berries. Deaths from the disease have not been well documented, but according to one 2012 research paper, there have been at least 41 deaths in the U.S. between 1990 and 2007
Research on wolves in Idaho and Montana by a team lead by Washington State University College of Veterinary Medicine researcher Willian J Foreyt between 2006 and 2008 revealed that 62% of wolves in Idaho and 63% of wolves in Montana were infected with the tapeworm.
A 2018 research study out of Colorado State University in Fort Collins, published in the Center for Disease Control’s Emerging Infection Diseases Journal says, “Although well studied globally, the current presence, prevalence, and transmission dynamics of Echinococcus spp. tapeworms in the contiguous United States are currently unknown. Substantial research was conducted between the early 1930s and the 1980s; however, very little research has occurred in the past 3 decades…Canada appears to be experiencing an increase in the presence and prevalence of E. multilocularis tapeworms, with spillover events starting to occur. If this asserted expansion is true, a similar expansion may be occurring in the United States.”
Thirty eight of Colorado’s 64 counties have passed formal resolutions opposing the forced introduction of Canadian grey wolves proposed by Lake George resident and CEO of the Colorado Wolf and Wildlife Center Darlene Kobobel and Gail Bell of Aurora.
Kobobel and Bell gathered the required signatures and the initiative has been placed on Colorado’s November 2020 state-wide ballot as a statutory measure.
But wolves aren’t waiting for an election, they are already here.