What to know about the gray wolf, whose fate in Colorado could be decided by voters

The gray wolf was once a "keystone species" in the western United States.

Colorado voters soon will have the unique opportunity to help decide the fate of an entire species.

A question on whether to reintroduce the gray wolf, a species widely eradicated in the western United States in the 1940s, has been added to the ballot.

The gray wolf, or Canis lupis, once roamed freely throughout much of the U.S. but was extirpated from most of the lower 48 states by the 20th century, according to the U.S. Fish and Wildlife Service.

The last gray wolf native to Colorado was killed in 1945, at the end of a 70-year campaign spearheaded by the federal government on behalf of the livestock industry, said Rob Edward, president of the Rocky Mountain Wolf Action Fund, the leading campaign in support of reintroducing the species to the state. Prior to that period, the gray wolf was a "keystone species" in the West, according to the organization.

Gray wolves are needed to restore the state's ecological balance, advocates say

Scientific data shows that wolves are "critical components" of the ecosystem and that their absence has negative consequences, Edward told ABC News.

Western Colorado, the area west of the Rocky Mountains where the reintroduction of the gray wolf has been proposed, is home to the largest elk and deer population in the U.S., Edward said. However, in places like Rock Mountain National Park, the animals are sedentary and browse all of the vegetation "down to the ground," which leads to erosion from rivers and streams and the disruption of other habitats.

This is largely because their biggest predators -- wolves -- are not causing the populations to move locations, Edward said.

Colorado is a "fine place for wolves to be" due to the habitat and plenty of "good prey," John Vucetich, a professor of wildlife ecology for Michigan Technological University, told ABC News.

In addition, wolves limit the spread of disease, such as Chronic Wasting Disease, by eliminating vulnerable animals from the population, according to the organization.

Wolves and humans can't coexist peacefully, according to the opposition

The Stop the Wolf Coalition, the leading organization opposing the initiative in Colorado, believes that reintroducing wolves to the state will actually lead to "unknown consequences" in spreading Chronic Wasting Disease because of the species' ability to travel vast distances, according to its website.

The coalition also believes that conflicts between humans and wolves is "inevitable" and that attacks on pets will increase due to a shrinking habitat.

In addition, the coalition warns that wolves can be a "significant factor" in the decline of big-game herds and that 43% of all confirmed livestock depredations by wolves occurred on private property. However, Edward stated that data from the reintroduction of the species to the Northern Rock Mountains shows that 99.95% of livestock in the region have not been affected.

A representative from the coalition did not immediately respond to ABC News' request for comment.

Colorado received enough signatures to add the vote to the 2020 ballot

Colorado's Department of State announced Monday that Initiative 107, titled "Restoration of Gray Wolves," qualified for the 2020 general election ballot after receiving more than 215,000 qualified signatures, 111% more than what was required.

This shows that the initiative has public support, Edward said, and Vucetich said he believes people's attitudes toward wolves are "sufficiently positive" and that the species and Colorado residents would "coexist just fine."

The measure would require the Colorado Parks and Wildlife Commission to create a plan to reintroduce and manage the species on designated lands west of the continental divide by the end of 2023.

It would also prohibit the commission from imposing restrictions on land, water or resources on private landowners for the plan and require state government to "fairly compensate" owners for losses of livestock caused by the wolves.

If approved by voters, the measure will take effect within 30 days after the vote is completed. It could be the first time in U.S. history that voters considered the reintroduction of a species.

In 2016, the Colorado Parks and Wildlife Commission stated that it supported the presence of wolves in Colorado but via natural migration, rather than reintroduction. The commission also urged that the wolves be allowed to live with "non-boundaries" where they find habitat and that they be left "wherever found," provided they are not causing problems. In addition, the commission recommended that conflicts with wolves be resolved using non-lethal methods and that funding for the wolves come from sources other than sales of hunting licenses.

The commission has not commented on the current ballot, according to ABC Denver affiliate KMGH.

Reintroduction into Colorado would not be immediate

Even if Colorado residents vote to reintroduce the gray wolf, the state will not have control over its future unless the species is removed from the federal Endangered Species Act in Colorado.

In March 2019, the Trump administration proposed to remove the gray wolf from its list of endangered and threatened wildlife and is expected to make a determination by March of this year. If the wolf is de-listed, reintroducing the species would still be a long-term process on how to proceed, which could include a period of public comment, Rebecca Ferrell, a public information officer with Colorado Parks and Wildlife, told KMGH last month.

If the FWS does not remove the gray wolf from the endangered list, state legislature would have to give the CPW approval to begin reintroducing the wolf, Ferrell said.

The FWS did not immediately respond to ABC News' request for comment.

Why scientists believe the gray wolf should not be de-listed as endangered

Two months after the Department of the Interior announced the proposal to remove gray wolves from the endangered species list, more than 100 scientists signed an open letter objecting to the proposal.

Vucetich and Michael Nelson, a professor of environmental ethics and philosophy at Oregon State University, both of whom signed the letter, argue that wolves do not yet meet the standard for removing them from the Endangered Species Act.

Wolves have been federally protected since they were added to the Endangered Species Act in 1978, which prompted the re-introduction of wolves in the northern Rocky Mountains in Idaho, Montana and Wyoming as well as the Great Lakes and Southwest, Edward said.

Gray wolves historically had the greatest natural range of living terrestrial mammals, according to the Smithsonian National Zoo. Today, they are distributed to the open tundra and forests primarily in Alaska, Canada and the northern U.S. -- at just 15% of their former range, both scientists said.

However, when the proposal to remove the gray wolf from the endangered species act was made last year, Secretary of the Interior David Bernhardt, a Colorado native, said the species "no longer meets the definition" of a threatened species.

The last estimate of gray wolves in the lower 48 states stood at 5,680, according to the FWS, which describe their populations as "stable" and "growing." However, the act states that the species must return to a "significant portion" of its former range, Nelson and Vucetich said.

"It's not about viability," said Nelson, citing the law. "It's really about geography."

The gray wolf populations were de-listed in the Northern Rocky Mountains in 2011 and 2012 due to population recovery and remain under state management, according to FWS.

Potential economic impacts in the state

The prevalence of the wolves could also reduce the quantity of animals available for hunting, such as deer and elk, according to the initiative. This could then have an economic impact on businesses that facilitate hunting as well as state and local government revenue from hunting-related fees and taxes.

Conversely, the initiative states that the presence of the wolves could have a positive effect on the health of some of the state's ecosystems, which will then promote participation in "non-consumptive" forms of outdoor recreation and could increase revenue to businesses and governments that facilitate those activities.