Trampled: sage grouse and feral horses on the public domain

EVER SINCE THE FIRST SPANISH ENTRADA, MYTHS HAVE HAUNTED THE AMERICAN WEST.

The Northwest Passage, the Seven Cities of Gold, Cibola, the Welsh prince Madoc and his band of colonists settling in the New World 300 years before Columbus, the Buenaventura River flowing from the west slope of the Rockies across the Great Basin and the Sierra Nevada Range to San Francisco Bay— flights of imagination have led generations of explorers to confusion, hard times, disappointment, and, all too often, death.

It took us nearly 400 years to purge these monumental errors in our understanding of geography and culture on the western landscape.  These days, the myths are smaller, but they persist.

Take, for example, the myth of the mustang.  As the story goes, these noble beasts are the direct descendants of the stallion Hernan Cortez rode into Tenochtitlan after he had subjugated the Aztecs.  Or perhaps the lineage reaches even further into the past.  Since the family tree of the equids is deeply rooted in North America, a few true believers argue, it could very well be that the horse never really disappeared from the New World.  Just look at the modern representatives of the breed, they say— the faint striping on haunches and legs of some wild horses shows a genetic link with some far-off ancestor that must have dodged the great Quaternary extinction that claimed mammoths, mastodons, ground sloths, and saber-toothed cats.  A further argument maintains that, even if the horse became extinct in North America, the species disappeared so recently that wild horses on the modern landscape are really just a reintroduction of a native species.

None of these assertions stands much scrutiny.  The notion that horses roaming free in the West are the pure progeny of Spanish mounts ignores the escape of untold thousands of horses and burros from travelers, native tribes, and ranches over four centuries.  Whatever “pure” blood may have established horses in the West has long since been overwhelmed by more recent contributions from these escapees.

While science has found fragmentary evidence of isolated herds of horses in North America that are more recent than the remains of mammoths and other extinct species, the overwhelming consensus in the scientific community is that the horse was extinct in the New World for several thousand years before the first Europeans hit the beach.  Since there is no evidence that paleohunters paid much attention to horses as prey, we’re left to conclude that the disappearance of the equine line in America was due to fundamental ecological change in the niche they occupied, not persecution by humans, whether armed with stone-tipped spears or rifles.

The notion that the escape of the modern domesticated horse in America is some sort of “reintroduction” simply ignores the evolutionary reality of extinction.  Modern humanity didn’t erase this species from the New World; it disappeared as a result of natural forces that came into play thousands of years ago.  We’re not well equipped to understand how those forces operated, but it’s more than a little arrogant to assume that a species returning from the dead can claim an ecological place on the modern landscape without any consequences.

These matters of prehistoric ecology and patterns of American conquest would be of little interest to anyone but paleontologists and historians . . . except that the growth of feral horse herds on the western landscape has thrown a huge monkey wrench into the day-to-day management of several million acres of the public domain.

Managing feral horses on the public range would be a relatively simple matter if the Bureau of Land Management (BLM) were allowed to treat them as any other livestock or game animal.  There is a market for horsemeat, hides, and other commodities— a sustained harvest of feral horses might almost pay for itself while maintaining horse populations at levels that would leave forage for domestic livestock and possibly even habitat for the host of wild animals that share the public range with these newcomers.  Fans of feral horses would still have horses; ranchers would have more forage for sheep and cattle, and wildlife enthusiasts would have more deer, pronghorns, sage grouse, and other wildlife that depends on the sagebrush steppe.

Alas, killing even a single feral horse is something a small, highly motivated group of extremists simply will not tolerate.  As a result of generations of their vehement demands, the BLM has cobbled together what seemed, over the years, to be a workable compromise.  Instead of killing surplus horses on the range, BLM officials proposed, we will trap them and allow people who care to adopt them.

There are some horse activists who object even to the process of trapping feral horses, arguing that the stress of being hazed by helicopters, confined in corrals, and shipped in trailers is unacceptably cruel, but most seem willing to tolerate the effect on individual horses in the interest of avoiding damage to public rangeland.

But three fundamental problems with the adoption program have emerged.

First, it’s expensive.  In 2023, BLM asked Congress for $154,800,000 for wild horse and burro management.[i]  Some of this supported efforts to control reproduction among feral horses, a project doomed to failure, partly because feral horses can be difficult to approach, partly because they don’t care to be sterilized, and partly because contraceptive drugs would have to be administered across the West on a regular basis in order to be effective.

Second, the BLM can’t find enough people to adopt feral horses.  In 2023, BLM paid landowners $109,000,000 to board feral horses that had been trapped but were not sold or adopted.[ii]  That outlay is likely to increase as the BLM increases the number of feral horses it traps and the number of people interested in adopting even more horses declines.

It’s becoming increasingly clear that BLM trapping and contraception together haven’t checked the growth of feral horse herds, which means that— third— there are too many horses on the public range.  In 2023, BLM had a goal of keeping no more than 26,785 feral horses and burros on the land it manages.  Official estimated that there were actually 82,883 on the range, an excess of 56,098 or about 300 percent more than the established ceiling for the breed.  Those numbers are likely to increase until feral horses have so degraded the range that they no longer have enough food to produce foals.  Or until we take a more practical approach to managing feral horses.

Wildlife biologists have long suspected that too many feral horses in the sage have affected many of the true native residents of the region.  In the last few years, carefully designed research has reinforced that view.  A study in 2021 concluded that “our models predicted a 70.9% reduction in sage-grouse numbers across approximately 4,500,000 acres of sage-grouse habitat in Nevada and northeastern California, assuming horse populations continue to increase at their current rates.”[iii]  A 2024 study in Wyoming found that “overabundant free-roaming horses negatively affected nest, brood, and juvenile survival”[iv] among sage grouse in the area.

There’s good reason to believe that too many feral horses may be just as bad for pronghorns as they are for sage grouse,[v] and that generalized effect probably applies to most of the other wildlife in sage country.

I think it’s safe to say that most wildlife biologists and conservationists familiar with the West would prefer to eliminate feral horses entirely from western rangeland.  With all the other stresses we’ve inflicted on the sagebrush steppe, the system would be far better off without this large, highly adaptable exotic in competition with native wildlife.  Clearly, the mustang constituency will never agree to this, the most ecologically sound, approach.

A compromise has to be made.  But that workable compromise would bear little resemblance to the breathtakingly expensive, largely ineffective system that’s been assembled out of mismatched parts under the provisions of the Wild Horse and Burro Conservation Act.  Feral horses should be managed with clearly defined objectives, just as all other wildlife and human activities are— or should be— managed on the public domain.  Contraception for feral horses may seem a humane option, but it isn’t practical or affordable.  It’s seems inevitable that a sustainable commercial harvest of feral horses would be part of any workable program.

It’s been said that the multiple-use approach to management of the public domain is all too often a justification for multiple abuse.  In 2023, the BLM admitted that half the rangeland it manages did not meet the agency’s own standards for healthy pasture.[vi] Half— 57,000,000 acres.  According to the BLM, overgrazing by domestic livestock is a significant reason for that condition on 38,000,000 acres, and, if even the BLM offers this estimate, it’s a good bet that the situation is substantially worse.

Across the West, feral horses are an insignificant part of range abuse, in large measure because feral horses are confined to specific, relatively small parts of the public domain.  Still, where they are too abundant, the research cited above shows that they’re not good for sage grouse and other wildlife.

Politically powerful interests in the cattle and sheep industry have fought federal efforts to manage the public domain effectively for well over a century.  Their abuses are the root of the problem on BLM land.  If the issue of feral horses intrudes on my concerns about the public domain, it’s because I suspect I share many of my views of conservation and environmental justice with the advocates of feral horses.  I suspect these people admire the wildlife of the sage as I do; I suspect they take pleasure in watching the sage country blossom.  I’m dismayed when I discover that they seem unwilling to accept a management regime that provides for sage grouse as well as for mustangs.

There is common cause to be made here.  The BLM needs a constituency that supports conservation— wise use of the range— before it can counteract the influence of the traditional interests that scalp the public domain for their own profit.  There has to be a limit on the number of cattle and sheep that graze on federal land.  There has to be a limit on the number of feral horses, too.  When the population of those horses is up to seven times the recommended maximum,[vii] it’s hard to mount a cogent defense of the way they’re being managed.

Caught between widespread abuse of rangeland by domestic livestock and the damage done in a few key areas by burgeoning herds of feral horses are all the native wild things that depend on the sage for food and shelter.  Those of us who speak for that last group aren’t asking for everything, but we insist on getting something like a fair share.

There are those who see the mustang as the symbol of the sage.  I much prefer the pronghorn and the sage grouse, the true natives, evolved over millennia in equilibrium with the land that nurtures them.  Whatever your preferences, it’s clear that the land can sustain only so much.  If there is to be balance on the modern landscape, ecological or ethical, we have arrange it; it won’t happen on its own.

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[i] Stone-Manning, Tracy, 2023.  The President’s Fiscal Year 2024 budget for the Bureau of Land Management.  U.S. Department of Interior.

https://www.doi.gov/ocl/blm-budget.  Accessed April 14, 2025

 

[ii] Waddell, Holle, 2023.  Wild Horse and Burro Program update.  https://www.blm.gov/sites/default/files/docs/2023-12/wildhorse_Holle-%20BLM%20WHB%20Program%20Update_Dec2023AdvBrdMtg.pdf

 

[iii] Coates, Peter S., et al., 2021.  Sage-grouse population dynamics are adversely affected by overabundant feral horses.  Journal of Wildlife Management 85(6): 1132-1149.

https://wildlife.onlinelibrary.wiley.com/doi/epdf/10.1002/jwmg.22089.  Accessed April 14, 2025.

[iv] Beck, Jeff, et al., 2024.  Free-roaming horses exceeding appropriate management levels affect multiple vital rates in greater sage grouse.  Journal of Wildlife Management 88(8): e22669.

https://wildlife.onlinelibrary.wiley.com/doi/10.1002/jwmg.22669.  Accessed April 14, 2025.

[v] Hennig, Jacob, et al., 2022.  Habitat selection and space use overlap between feral horses, pronghorn, and greater sage-grouse in cold arid steppe.  Journal of Wildlife Management 87(1): e22329.

https://wildlife.onlinelibrary.wiley.com/doi/10.1002/jwmg.22329.  Accessed April 14, 2025.

 

[vii] Beck, Jeff, et al., 2024.  Free-roaming horses exceeding appropriate management levels affect multiple vital rates in greater sage grouse.  Journal of Wildlife Management 88(8): e22669.

https://wildlife.onlinelibrary.wiley.com/doi/10.1002/jwmg.22669.  Accessed April 14, 2025.