New Mexico’s wildlife diversity once puzzled scientists, but its study helped us better understand where animals live and why. Now, in the face of a changing climate, the Land of Enchantment again offers vital lessons for understanding—and protecting—wildlife.
Bighorn sheep have made a resurgence, with more than 1,700 throughout northern New Mexico. Photograph by Minesh Bacrania.
IT’S NOT EASY to pick a beginning for New Mexico’s wildlife story. Some 23,000 years before White Sands became a national park, footprints left in mud by a young woman carrying a child on her hip intersected with those of a giant ground sloth, indicating an ancient and alarming close encounter. Ten thousand years later, hunters left spear points in the remains of multiple now-vanished mammoths near the present-day town of Clovis. Subsequent Indigenous people, including Puebloan farmers and Plains hunters, preserved New Mexico’s biological diversity for the next 10 millennia. When Europeans arrived, explorers like Francisco Coronado, Albert Pike, George Ruxton, and Josiah Gregg documented mountain streams brimming with beaver-dammed pools and plains resembling an American Serengeti filled with grizzlies, wolf packs, and jackal-like coyotes trailing vast herds of bison, elk, and pronghorn.
But maybe the most resonant start to the New Mexico wildlife story came a century ago, when naturalists Vernon Bailey and his wife, Florence Merriam Bailey, began studying New Mexico’s biological riches and ecologies. They were followed to New Mexico by another scientist, Aldo Leopold, who rearranged the furniture in our heads with respect to what we knew about conservation. Writing from Santa Fe, popular wildlife author Ernest Thompson Seton penned heartrending stories of New Mexico animals, such as Tito, the female coyote who allegorically taught the species how to avoid extermination, and the Ratón-area wolf Lobo, King of Currumpaw, who possessed one fatal flaw: his fidelity to his mate. Seton’s literary theme—“we and the beasts are kin”—aligned with long-held Native perspectives.
Andre, a six-month-old black bear cub, was photographed for Randal Ford’s "Animal Kingdom." Photograph by Randal Ford.
What the Baileys, Leopold, and Seton provided were simple but crucial ways to understand New Mexico and its wildlife.
A hundred years ago, New Mexico’s riot of diverse ecologies and abundant mammal species—151, more than any state except California—struck many observers as an almost chaotic natural world. The Baileys were essential in changing that perception. Vernon, a farm boy from Minnesota with seven years of schooling, never even heard of Charles Darwin until his 20s. But Vernon was such a whiz at catching animals and preserving them as specimens that he became the right-hand man to Clinton H. Merriam, who in the 1890s was establishing a new federal agency, the Biological Survey, which became the U.S. Fish and Wildlife Service.
Merriam’s younger sister, Florence, seemed the unlikeliest imaginable partner for Vernon. A graduate of Smith College, she originally planned a thesis on Darwinian evolution. But an environmental crisis—the destruction of birds for hats and fashion—diverted her toward writing about birds, their steep decline, and preservation. Their pairing raised eyebrows, but Florence and Vernon Bailey married in 1899 and struck out the following year on a field expedition across Texas and New Mexico for their honeymoon. “We felt everywhere in New Mexico, [that] while to us the country was new, in very fact this land of poco tiempo is an old, old land,” she wrote.
Aldo Leopold pulls a skiff across a Río Grande mudflat in 1918.
Photograph courtesy of the University of Wisconsin–Madison Archives.
Vernon began working to make sense of New Mexico’s puzzling wildlife distribution. Why were certain species of animals found in some locations but not others? Vernon and Merriam believed they knew, pioneering a model called “life zones.” In a territory where elevation ranged from 2,800 feet to more than 13,000 feet atop Wheeler Peak, Vernon mapped out six life zones for plants and animals. He named them Lower Sonoran, Upper Sonoran, Transition, Canadian, Hudsonian, and Arctic-Alpine. In a 1913 monograph in North American Fauna, Vernon described the existing species compositions of all six zones in the brand-new state and made its wildlife distribution newly intelligible.
Vernon is remembered for the role he played in designing (and defending) wolf eradication, but taxonomists also credit him with realizing that our now endangered Mexican gray wolf was different from other wolves, which is why its Latin binomial carries Bailey’s name—Canis lupus baileyi.
Florence’s Birds of New Mexico (1928) was the first close ornithological study of an interior U.S. state. She also authored the first field guide for Western birds and added a whopping 94 new species to the lists for New Mexico and the Southwest.
“A hundred years ago, New Mexico’s riot of diverse ecologies and abundant mammal species—151, more than any state except California—struck many observers as an almost chaotic natural world.”
Seton and the Baileys experienced New Mexico at a time when market hunting excesses were destroying numerous species that had anciently evolved in America. In the 1870s, an industrial-scale hunt for hide leather eradicated bison on the Southern Plains, sacrificing millions of animals Native and Hispanic New Mexicans had long depended on. But that was just the beginning. By the early 1880s, naturalist Lewis Dyche found no bighorn sheep while exploring the Pecos River headwaters, “no elk in the country except a rare and occasional straggler,” and neither saw nor heard the howls of any wolves. He did observe a single “herd” of 11 grizzlies traversing Hamilton Mesa.
Although Americans made an effort to save some of these animals, they largely concerned themselves with the ones we called “game”—birds and mammals desirable to hunters. Game and Fish agencies in the various states were the widespread result. There was little appreciation for nongame or even for species that had evolved here. State-sponsored exotic species introductions for hunters (think ibex, oryx, and aoudads) in fact became a New Mexico specialty.
New Mexico’s Mexican gray wolf population has increased slightly in recent years.
Photograph by Shutterstock.
The new federal public lands did preserve wildlife habitats, though, and Leopold spent enough time working in New Mexico during the early 20th century to shape future wildlife policy. Stationed here to manage Carson National Forest, Leopold met his future wife, Estella Bergere, in Santa Fe. He went on to study a phenomenon called “game irruptions”—the unchecked growth, then spectacular crash of populations of mule deer and other ungulates—that followed America’s and New Mexico’s eradication of predators on behalf of the livestock industry. Leopold found almost no record of irruptions before 1900 but tracked a whopping 42 between 1900 and 1945. His work and the growing significance of ecological science slowly began to produce an appreciation for nongame, even for predators like wolves, lions, and our unofficial state animal, coyotes. The 1976 listing of the Mexican gray wolf and its later recovery plan under the new Endangered Species Act was an extension of Leopold’s work. Ending coyote-hunting contests on state lands was another.
While the century-old life zones model continues to have some relevance in organizing New Mexico wildlife, the science of ecology—with its emphasis on interactive communities known as ecosystems—and subsequent work in mapping “ecoregions” has advanced our understanding of New Mexico’s once-seemingly chaotic diversity. In a state split by the Continental Divide, where the Great Plains, Rocky Mountains, Colorado Plateau, and Southwestern deserts all converge, ecological diversity is enormous. At a fine-grained level of mapping, the state features eight principal ecoregions (such as the Southwestern Tablelands) divided into an astonishing 55 ecological subsets (piñon/juniper woodlands, for example).
A prize Gila trout.
Photograph courtesy of the New Mexico Wildlife Center.
Add in New Mexico’s geologic deep time history, and the state’s special qualities stand evident. Twenty thousand years ago, the Wisconsin Ice Age pushed northern species far south. Later, massive heat events, like the Altithermal of 8,000 to 5,000 years ago, expanded southern and desert species northward. When Vernon Bailey was in New Mexico searching for remnant bighorn sheep, he discovered that jaguars were hunting and breeding in the vertical ridges of the Black Range and in mountains like the Sangre de Cristos. In other words, New Mexico jaguars—at the northernmost edge of a range that stretches down through the Americas—were preying on Rocky Mountain bighorns at the southernmost tip of an alpine habitat stretching far northward up the mountain chain. Not many places on the continent can make a claim like that.
Today, Mexican gray wolves—whose tiny population has so little genetic diversity it struggles to survive—are New Mexico’s most famous endangered animals. But a state so ecologically varied has many more species in peril, 64 in all. If New Mexicans hope to experience what Henry David Thoreau once called “an entire heaven and an entire earth,” we must save Mexican spotted owls, Northern aplomado falcons, Southwestern willow flycatchers, Gila trout, black-footed ferrets, meadow jumping mice, and ridge-nosed rattlesnakes.
“Today, Mexican gray wolves—whose tiny population has so little genetic diversity it struggles to survive—are New Mexico’s most famous endangered animals.”
We’re working on all that. As part of a national initiative, New Mexico’s State Wildlife Action Plan is designing strategies to conserve our “species of greatest conservation need,” along with their habitats, to confront human-caused climate change that threatens to make an already arid state drier and hotter. Anticipating and protecting connectivity corridors so that species are able to relocate to new habitats is part of that plan. So is preserving as much genetic diversity as we can. And—I’m being personal now—our polestar ought to be a future where we return as many of those original New Mexico species to the state as possible. I want to see muscular jaguars once again pursuing Rocky Mountain bighorns in our mountains.
While a name change may seem merely symbolic, when the 2025 legislature voted to retire the New Mexico Department of Game & Fish and brand it the New Mexico Department of Wildlife starting next July, we met a crossroads and took the right path for the 21st century. You have to think that Vernon and Florence Bailey, Ernest Thompson Seton, and Aldo Leopold would be nodding in approval.
