When in the late nineteenth century millions of cattle and sheep invaded the ecosystems of the American West, it produced, as historian Donald Worster writes, “the explosive, shattering effect of all-out war.” Native plants were trampled beneath hooves and replaced with forage preferred by stockmen, grasslands were denuded and desertified, soil eroded and blown on the wind, rivers and streams were diverted, dewatered, and polluted by a cocktail of pesticides, fertilizers, and cattle feces. The communities of fish, reptiles, insects, and birds that depended on healthy riparian environments spiraled into chaos with the coming of the alien ungulates. Wolves, bears, and other so-called predators were trapped, gunned down, and poisoned to protect livestock. For the past century, says Worster, mainstream historians have ignored this war on wildlife. “[M]uch effort has gone into calculating the collapse of the native human populations under the European invasion,” he writes in his collection of essays, Under Western Skies, “but almost none into the precipitous decline of the many nations of wild animals.” A biocentrist tragic history of the West has yet to be written.

We are blessed, however, with the existence of a U.S. government agency that happens to have documented at least some of the destruction—because it was responsible for it. In the March issue of Harper’s Magazine, I investigate Wildlife Services, a branch of the Department of Agriculture that is notorious among activists but largely unknown to the public that has financed its operations for more than a century. In the West, where much of its lethal work has been conducted, the agency mostly serves the interests of cattle and sheep ranchers. Former Wildlife Services trapper Carter Niemeyer, in his 2012 memoir Wolfer, goes so far as to assert that many of its employees have acted as “the hired guns of the livestock industry.”

Since 1915, when Congress first funded federal trappers specifically for the purpose of eliminating wildlife that posed a threat to livestock, Wildlife Services has been responsible for the deaths of tens of millions of animals. It has killed coyotes, wolves, foxes, black bears, grizzly bears, cougars, bobcats, and wolverines. It has killed animals deemed “pests” by stockmen: beavers, prairie dogs, minks, martens, muskrats, badgers, pocket gophers, ground squirrels, jackrabbits, opossums, porcupines, skunks, raccoons, and weasels. It has killed eagles, crows, ravens and magpies. Between 2000 and 2014 alone, two million native mammals fell before Wildlife Services, including twelve taxa of mammals listed as endangered, threatened, or as candidates for protection under the Endangered Species Act.

The agency has always taken its direction from Western stockmen. When bison, elk, and deer were hunted to near extinction at the turn of the 20th century, the wolves and the cougars and the bears looked to cattle and sheep for food, as their natural supply dwindled. The cattlemen and sheepmen in turn placed bounties on the predators, but the bounties failed to solve the problem. By 1900, the stockmen’s associations were lobbying federal authorities to complete the job they could not. With the founding of the Forest Service in 1905 under its first chief, Gifford Pinchot, federal authorities bowed to the demands of what Pinchot described as “the best-organized interest in the West,” and established a program for the extermination of wolves and coyotes in the national forests.

The Forest Service sought help from an obscure research arm of the Department of Agriculture called the Bureau of Biological Survey, whose biologists it tasked with identifying and tracking predators so that forest rangers could swoop in for the kill. In 1915, the Bureau of Biological Survey took over lethal predator control as a full-time operation. Thereafter it thrived under the steady hand of Congress. In 1931, with the passage of the Animal Damage Control Act, Congress expanded the agency’s purview and funding, directing it to “conduct campaigns for the destruction” of any “animals injurious to agriculture.” By 1947, the agency had singlehandedly persecuted wolves to remarkable success: wolf populations were drastically reduced in the continental United States.

In 1971, a reporter named Jack Olsen investigated Wildlife Services, then known as Animal Damage Control, in a series of articles for Sports Illustrated, which he published later that same year in his book, Slaughter the Animals, Poison the Earth. Olsen remarked on the close relationship between livestock producers and government trappers, the shared cultural attitude toward wild things. “[T]he hatred of sheepmen for coyotes, bears and mountain lions,” wrote Olsen, “seems to go so far beyond the dimensions of reality as to be almost pathological in origin.” Former trapper Dick Randall, who left the agency in the 1970s to become an activist with the Humane Society, described how a rancher working with Animal Damage Control dispatched coyotes. “[H]e takes a burlap bag, cuts out a hole for the head and two holes for the front legs, pulls the bags on the animals, pours kerosene on, sets them on fire and turns them loose. And he laughs when he tells that, as if it were the greatest thing!” Activist Lynn Jacobs, author of Waste of the West, compiled dozens of such accounts. Jacobs writes of ranchers who “torment trapped animals by beating, stoning, burning, shooting, or slashing them. Or they may saw off their lower jaws, wire their jaws shut, blind them, cut off their legs or tails, or otherwise mutilate them and then release the unfortunate animals.” Olsen told the story of a sheepman on the Frio River in Texas “who liked to saw off the lower jaws of trapped coyotes and turn the mutilated animals loose for his dogs to tear to pieces.” He wrote about “a rancher and his wife and children who spent a delightful winter weekend cruising their property on snowmobiles, throwing out strychnine ‘drop baits’ to kill coyotes….The Western stockman who does not engage in such popular practices is branded an eccentric.”

Olsen described how federal predator control agents, moving beyond the simplistic trapping and shooting that had characterized the methods of the stockmen’s bounty system, innovated in the 1940s the dissemination of deadly poisons on public land. Among the preferred weapons was thallium sulfate laid in baits and in carcasses, which persisted in the food chain, producing secondary and tertiary poisonings, and caused untold numbers of deaths of wildlife feeding on carrion. The newly developed toxic compounds, as Olsen wrote, “turn[ed] the tortured rangelands into a reeking abattoir of dead and dying wildlife and contaminated watersheds.”

In 1946 Animal Damage Control debuted the use of sodium fluoroacetate, otherwise known as Compound 1080. Tasteless, odorless, and colorless, described as a “super poison” by the FBI, it has no known antidote. A single ounce can kill 200 adult humans, or 20,000 coyotes, or 70,000 house cats. For decades, the agency distributed Compound 1080 like candy across the West, mostly targeting coyotes. The effect of 1080 on canids is horrific. It produces “a frenzy of howls and shrieks of pain, vomiting, and retching,” attacking the central nervous, respiratory and cardiovascular systems before ending life in cardiac or respiratory arrest. (Following the invasion of Iraq in 2003, an Iraqi military official claimed that Saddam Hussein used 1080 extensively to eradicate political opponents.) Between 1960 and 1970, Animal Damage Control agents laid on public and private lands 156,378 meat baits of 1080 and about 1.5 million pounds in the form of grains. Enough poison of various kinds was spread on the Western range in a single year during the 1960s to kill every man, woman, and child west of the Mississippi, according to Olsen.

By the 1970s, rangeland ecologists were raising an outcry, calling for reforms. The 1972 report of the Advisory Committee on Predator Control, commissioned by the Department of the Interior, found that the agency, now christened the Division of Wildlife Services, “contain[ed] a high degree of built-in resistance to change.” The investigators, led by University of Michigan ecologist Stanley A. Cain, remarked that “several hundred control agents today are the same persons for whom…the job requirements and measurements of an agent’s success have been the killing of large numbers of predators and of personal, uncritical response to the complaints of stockmen….Agents are frequently long-time acquaintances, friends, and neighbors of the individuals demanding service.” The Cain Report, as it was known, advised “substantial, even drastic changes in control personnel and control methods.”

Such was the concern about Wildlife Services’ policies that the most notoriously corrupt president in modern history, Richard Nixon, who privately derided conservationists as “hopeless softheads,” issued in 1972 an executive order that included a ban of the use of thallium sulfate and Compound 1080. His administration authored a bill, the Animal Damage Control Act of 1972, which, if passed—it didn’t—would have repealed Wildlife Services’ enabling legislation of 1931. Nixon had read the Cain Report, and publicly praised it. He lamented that “persistent poisons” had been spread across the American landscape “without adequate knowledge of the effects on the ecology.” He talked about “an environmental awakening” and “a new sensitivity of the American spirit and a new maturity of American public life.” He told the country that “the old notion that the ‘only good predator is a dead one’ is no longer acceptable.”

Nixon got it wrong. At Wildlife Services there has been no environmental awakening, no new sensitivity, no new maturity. The only good predator is still a dead one. The public continues to pay the price. In reporting my article for the magazine (“The Rogue Agency,” March 2016) I discovered dozens of examples of senseless destruction resulting from Wildlife Services’ actions and policies. It will suffice here to recount one of these tales that didn’t make it into print.

In May 2008, Brooke and Cliff Everest, a couple from Bozeman, Mont., embarked on a rafting trip on the White River of Utah. One day during the trip, on a hike they had taken after beaching their boat on public land, their dog, an American Brittany named Bea, inspected a carcass of an animal in a canyon. Later that day Bea descended into the throes of poisoning. Cliff and Brooke Everest wrote an account for the nonprofit activist group Predator Defense:

“We were totally mystified as Bea went from a dog calmly lying around camp through a progression of ever more bewildering symptoms. After seeing her heaving and trying to vomit, she suddenly jumped into Brooke’s lap with a scream of pure terror. She then charged around camp, jumping in and out of the raft, crying and yelping in a frenzy of fright and pain. Our efforts to calm her had no effect. She ran a high speed circuit around camp, accidentally slamming into our friend sitting in a chair, then launched off the raft into the river and started swimming for the opposite shore…. Our frantic calls were ignored as the current carried her downstream. She finally turned back towards our side of the river, but when she reached shore, she raced away from us. We found her collapsed under a bush in violent convulsions with a frightening stare, pounding heart, gagging and gulping for air. After 15 more minutes of this agony, Bea died and her body immediately became very rigid. We carried her stiff, lifeless body back to camp and buried it under a cottonwood tree.”

Every indication suggested she had been killed by Compound 1080, which continues to be used by stockmen and Wildlife Services agents in ways that violate federal law—and render our public lands into places of torture and death.

Read Christopher Ketcham’s article on Wildlife Services in the March issue of Harper’s Magazine.