Spirit of Nature: Field Notes on Natural History of the Rio Mora National Wildlife Refuge

Veteran conservation biologist and conservationist Brian Miller, who has worked in the Northern Rockies, Mexico, and the Southwest, moved from the Denver Zoo to manage the Wind River Ranch in northern New Mexico in 2005. He writes that during his forty-four-year career, he avoided being deskbound as much as possible and his first love has been field work where he could do research and closely observe nature around him. Wind River Ranch has given him an exceptional opportunity to engage these passions, and he shares them in Spirit of Nature. Philanthropists Clare and Eugene Thaw, who had retired to Santa Fe, New Mexico from New York, decided to gift their 4225-acre Wind River Ranch near Las Vegas, New Mexico to a non-profit for conservation and research. They hoped the Wildlife Conservation Society (WCS), a consortium of zoos and aquariums in New York City would accept their gift, and Brian, employed at the Denver Zoo and a prominent conservation biologist and advocate in the region, was invited by the WCS to submit a management plan, which he did. He shared it with Gene who liked his ideas, and when the WCS board refused Thaw’s offer, the philanthropist created the Wind River Ranch Foundation and hired Brian to manage it for research and conservation. Brian began work in 2005.

With his sharp biologist and conservationist eyes, Brian observed and recorded the ecology and phenology of the ranch. This book, written for the amateur naturalist and nature lover, is a month-by-month account of wildlife and natural history of this unique place which lies in the transition zone between the Sangre de Cristo Mountains to the west and the Great Plains to the east. Before he shares his “field notes,” however, Brian tells the story of how the Rio Mora National Wildlife Refuge came to be. It is a story of generosity, partnerships, and bureaucratic fecklessness (my word, not Brian’s). Eugene Thaw was “averse to government bureaucracy,” but he could not find an NGO to accept his gift and his conservation terms, so he decided to sell it on the open market. By this time Brian and others had established rich partnerships with the Jicarilla Apache and Pueblo of Pojaque, New Mexico Highlands University, nineteen school districts in the area, and launched “ongoing ecological restoration projects, bison and prairie dogs for grassland restoration,” and created a nexus for discussion of conservation in the region.

Hoping to avoid sale of the ranch to developers who would terminate all the conservation work done there, Brian approached the US Fish and Wildlife Service (USFWS) about buying the ranch, continuing its programs, and making it part of the federal refuge system. They agreed to pursue the idea, and Eugene decided to donate the land to the federal government after all. Miller is modest about all this, but he proved an adept diplomat, and his efforts ultimately led to establishment of the Rio Mora National Wildlife Refuge. Though the ranch was saved from private development, its path from 2010 to the present was a difficult one. Only in 2019 was federal funding for staffing and operation finally provided. Summing up the long struggle and frustration to adequately fund the new refuge, Miller writes “Despite receiving free land, expenses for eight years, and then a budget with no effort on the part of the USFWS, bureaucracy and Covid hindered education and research efforts by New Mexico Highlands University on the refuge.” The dedication and persistence of Brian and his colleagues was finally rewarded, and the refuge was finally placed on stronger footing of staffing and funding.

In Part One of the book Brian tells this story and describes the extensive conservation research and restoration that has been done over the past two decades despite many uncertainties. He also describes the many partnerships that have restored bison to the ranch and allowed pursuit of research, education, and restoration projects. He notes, “I think a lesson here is that nothing can be considered permanent” and a future for the refuge is certainly not assured. He continues, “Conservation requires science, active citizens, and government action. Don’t expect someone in power to make the right decision. Make them make the right decision.”

Surely one motivation for writing this book was Brian’s desire to share with us the beauty and nature of this place, and the vehicle he chose was to present, in Part Two, a month-by-month phenology of the Rio Mora National Wildlife Refuge. It is a small refuge, and little known, but perhaps if people know what is there, they will appreciate it and rise in its defense should that be necessary which—and I rather than Brian say this—is likely to be necessary given the anti-conservation politics in play in 2025. Veteran conservationist that he is, Brian understands that only if people love a place will they rise in its defense, so he explains how much there is to love about the Rio Mora NWR.

After a description of the landscape around the refuge, illustrated with some photographs by his daughter Anabella, photos by colleagues, maps, and some of his own and daughter Mary’s sketches, Miller moves on to Part Two which is the phenology. As the dictionary defines it, phenology involves study of climate and “periodic biological phenomena.” Fittingly this definition includes the word “climate” because while climate has always been part of the annual round of biological activity on the land, it is even more a part of the story in this age of climate change which is very much on Brian’s mind in his account. An observer compiling a phenology records the timing of concurrent events throughout the year and describes the interactions between diverse events happening at the same time on the landscape. The story at Rio Mora involves 189 bird species, 29 amphibian and reptile species, 51 mammal species, and myriad species of insects and plants, so Brian makes no attempt to be comprehensive in his treatment of this incredibly complex ecological community. He covers highlights.

The “Field Notes” are organized monthly, with the late fall and early winter months when activity is relatively slow presented in two-month intervals. As it increases with emergence of spring through summer abundance and into early fall, he divides his treatments into 10 to 15-day segments. For instance, during March 16-31 the Spring Equinox occurs and Brian explains this astronomical event and its significance. Spring bird migration begins, and the earliest butterflies emerge. Then in the April 1-10 period more birds arrive, some to stay, some to continue their migratory paths northward, insects begin to appear, and plants like Easter daisies and purple pasque flowers bloom.

The field notes are not dry recitations. He spices up descriptions of progression through the seasons with fascinating asides about natural history. For instance, in his treatment of March he includes a brief essay on “An Evolutionary Agreement Between Jays and Pines” in which he tells a good scientific story in clear, non-technical language of how birds like Clark’s nutcracker and piñon jay live in mutualistic association with whitebark and piñon pines. “The pine nut feeds the jay, and the jay stores the seeds in caches far from the mother tree, acting as an agent of dispersal. In return for food, the piñon jay thus helps the piñon pine reproduce… Because of caching, piñon jays nest in winter. Nestlings eat insects in the spring.” The book is rich in biological insights like this explaining how the species he observes at Rio Mora are adapted by eons of evolution to this place and time.

Moving forward to August, when activity slows down a bit, Miller offers more lengthy discussions of the natural history of Rio Mora. One of the long-term projects has been to restore bison and prairie dogs to the refuge and to study what happens. These are two species that have been driven nearly to extinction across the West, and he tells the sad stories of their decline. Working with Native American partners, bison have been returned to the refuge, as have prairie dogs, though the latter were wiped out by plague nearly a decade after they had been reintroduced (to be reintroduced again when the plague vector is controlled). Prairie dog populations, he notes, have declined in North America by 97%-98% pushing them to the edge of extinction. They are important to the grassland community, as he explains, and their conservation is essential for healthy grasslands. Brian writes of bison that “of all the ungulates facing extinction in the late 1800s, only the bison has been unable to recover significant wild numbers. They are near ‘functional extinction.’” Both species remain too low in numbers to maintain a functional role in grasslands. “When ecosystems lack functional species and processes,” he writes, “they degrade—as we see on many western grasslands.” Informative observations like this break up the sequences of the comings and goings of species through the months and are enjoyable and enlightening to read.

This book is about a small corner of America, a remote place in the high, dry grassland of a large western state, but it is about more than this place. Brian Miller writes about what is going on in the natural processes there. The details may be different in other places, but many of the issues and processes are the same. One hope he shares about this book is that it will be followed by other biologists and naturalists who will write about and share with their communities the issues and fascinating natural processes going on around them, perhaps at some of the 560 national wildlife refuges in the USFWS system. Using the phenological method of Spirit of Nature is one good way to approach this. In this moment of climate change when many people do not believe it is real, a chronicle of climate-related changes can be eye-opening.

Writing this book was a labor of love for Brian Miller—that is clear from the way he expresses his fascination for and love of the landscape and natural community he describes. The book was, in some ways, a family project with photography and artwork by family complementing his writing. It is not a fancy, glossy production—the word “homespun” comes to mind, down to earth and very accessible. Probably, for a book like this, rather spartan budgetarily. Miller often speaks directly to the reader in the second person, writing in a personal and intimate style, drawing us into his topic. He is a literate scientist. I live on the other side of the Sangre de Cristo range in northern New Mexico, and this place is different from Rio Mora but not entirely so. When I see the mourning cloak butterfly this spring, which appears very early around here, too early it has often seemed to me, I’ll understand why it is first. It has not been wintering in a pupal stage but as an adult under loose tree bark or in a tree cavity. I didn’t know that, Brian revealed it to me, and now my delight in seeing them in March will be even greater.

Wherever you live, if you love and care about the natural world around you, this book by a knowledgeable and wise conservation biologist will enhance your experience of your place. He will answer some of your questions and encourage you to “get out and explore wild places. Given the lack of action on climate change, it is best to do it sooner than later.” Good advice, yet he is not a pessimist. He is a dogged conservationist who knows what needs doing and how to do it as he has proven at Rio Mora. Like many conservationists who follow closely the challenges faced by the wild and are deeply concerned, Brian Miller has made the choice to do what he can to fight back. His many projects at Rio Mora and this book are examples of stalwart defense of the natural world. He encourages us to follow his lead.

Get your own copy of the book here: Spirit of Nature: Field Notes on Natural History of the Rio Mora National Wildlife Refuge.

Note: Brian Miller has been a contributor to Rewilding Earth. Check out what he’s written here.