Thousands of years ago, some of the earliest humans known to inhabit North America found shelter on a ledge by what is now known as the Gunnison River. The southeastern exposure of the rock overhang offered not only shelter from rain, snow and wind, but cool shade in summer, warm sunshine in winter, and unlimited plant food, fish and game. They settled in and made their home on the bank of the river for thousands of years.
When Bureau of Land Management archaeologist Glade Hadden with the Uncompahgre Field Office in Montrose first got wind of Eagle Rock Shelter after it was reported to the BLM in 1988, the site had been heavily and repeatedly vandalized. The BLM recorded Eagle Rock Shelter, also known as "SDT 813" -- the 813th site recorded in Delta County, as a looted site.
Hadden first recognized it as a Ute occupation. Evidence of their culture included post holes used in lean-to shelter construction that still held wood fragments, and a single hearth tucked in the back of the overhang. There is also rock art, and lots of it, covering almost every inch of the overhanging rock face and which has yet to be dated. The sun has taken a toll on the pigments, but drawings common to Utes and other cultures are clearly visible.
And while outward appearances suggested looters took everything related to the Utes, Hadden suspected the thieves might have missed something. By the contents of the "looter's pile" he reasoned they took only a few projectile points. "They missed all of the good stuff."
Evidence also suggested the site contained an archaic component dating back about 4,000 years. That's to be expected, said Hadden. Almost every rock shelter in this country dates back to about 4,000 years, but never beyond that.
Despite heavy looting, the site looked interesting enough to warrant further investigation. Hadden saw great potential for a field study for college students, especially since they couldn't do any more damage than the looters had. The BLM contracted with Western Wyoming Community College and Dr. Dudley Gardner, a professor of history and archaeology with whom Hadden had previously partnered, for archaeology students to work on the site.
Gardner's students began excavating in 2007. In year one they unearthed a 300-year-old Ute fire pit and projectile points dating back at least 3,000 years, including pre-Columbian Fremont Points, which are rare in this area, said Hadden.
In year two students hit a layer of rock marking where looters stopped digging. Experts reasoned the thieves assumed they'd hit bedrock and moved on. It was determined that the rocks were washed in by a flash flood that occurred as recently as the 1880s, and the rocks were removed and digging resumed.
Beneath the rocks students began finding undisturbed context dating back 4,000 years, 5,000 years and 6,000 years. When they found
ePaleo-Indianvidence of occupation dating back 7,000 years, Hadden realized the place was incredible. In his almost 20 years with the BLM, "I have never seen a site this old before."
In 2011, the excavation revealed something even more remarkable: a hearth, located below another hearth. First estimates placed it at about 9,000-10,000 years old, but that was wrong. Testing dated the hearth at 12,960 years old, making Eagle Rock Shelter the oldest known site in Colorado.
"It's hard to convey the excitement." said Hadden with the enthusiasm of a kid on Christmas morning. It pre-dates the Clovis culture by about a thousand years. In all of North America, about a half dozen sites this old or older are known to exist.
"There are older sites, no question," he said, and there are bigger and more beautiful and impressive sites and other stratified rock sites. Squint Moore Shelter on the Uncompahgre Plateau dates back 4,000 years to the Middle Archaic period, and Christmas Rockshelter includes Ute, Fremont and Late Archaic components, but nothing earlier. But what made the site unique was that they'd found something no one else had ever seen before, a record of Paleo Indian occupation. "We have the only, and I mean the only stratified Paleo site in the world." The site, not much bigger than a small house, provides a complete record of their culture over an extended period of time dating from between 13,000 and 8,000 years ago, with no gap in occupation.
"People lived here on a regular basis for a long period of time," he said. And why not? "It's the perfect place."
Virtually everything found was typical of hunter-gatherer sites, including seeds, fibers, berries, and some of the earliest known corn in North America, dating back almost 2,400 years. Animal bones revealed a diet of fish, rodents, and small-game animals including rabbits and martens. The largest bones found were from mountain sheep.
But they found no evidence whatsoever that occupants hunted or consumed mega-fauna -- big mammals including mammoths and ancient bison that roamed the area through the ice age. There were no diagnostic tools of the time, no big-game or large hunting points of any sort. "They were classic hunter-gatherers," he said. "Sixty-percent of their diet was from plants."
That's huge, said Hadden, who wrote his Master's thesis on re-evaluating Clovis as specialized mammoth hunters. Since about the 1950s the generally accepted paradigm says Paleo-Indians were highly mobile mammoth hunters of the plains that traveled at a great rate of speed, killing every big mammal in sight before moving on. In the past decade, opinions were shifting, but there was no evidence of continued occupation. "Here it is," he said. "For the first time anywhere, we have evidence to contradict the theory that Paleo-Indians were specialized big-game hunters."
In the world of Paleo-Indian archaeology, it's one of the most important findings in the world, said Hadden. It shows that Clovis were not the first inhabitants in North America, and that the Paleo-Indians didn't kill off the mega-fauna.
"We know it's going to receive a tremendous amount of scrutiny from the archaeological community," he said. To back their findings, Dr. Gardner hired Alpine Archaeological Consultants to excavate a unit within the site, but with no shared knowledge of their findings. The consultants' findings matched.
The site has garnered attention from around the world, including from Lee University, Northwestern Colorado College, the universities of South Africa and New Zealand, and from the National Museum of Mongolia and the New Zealand Conservancy. A consortium of institutions through Yale University put the site on its world tour and brought in top archaeologists from around the globe to survey the site.
The site is important because of the Paleo-Indian component, but that is far from the only significant component, says Hadden. "We have some of the most amazing stuff ever found in archaeological sites in Colorado right here. They're not unique, but they're amazing." In all, the site contained more than 50 hearths, and at least 42 different occupational contexts, including some gaps in occupation later on. In one of those layers was a 7,000-year-old woven yucca fiber basket that archaeologists estimate looters missed by about eight inches. It's the oldest known basket in Colorado and the second-oldest basket found in North America. "And it has a nice provenance," said Hadden. "We know exactly where it came from... And the dry climate has maintained it beautifully."
Another find that could be a game-changer is a Middle Archaic Pinto point with sinew wrapped around the base. Pinto points, found in this area, are thought to date 5,000-6,000 years, but the sinew dates back 8,000 years. That could push the occupation dates of sites in the Escalante Canyon near Delta back possibly 2,000 more years, said Hadden.
They also found tanned animal hides, a yucca-fiber sandal, and hundreds of projectile points, some dating back 12,000-13,000 years.
But to Hadden, the most significant find is that human behavior has remained largely unchanged throughout time. The Paleo culture didn't specialize in hunting mammoths and other large animals. "They specialized in what human beings have been doing throughout the millennia."
With the exception of some remaining work by Lee University students, excavation and data recovery are complete, said Hadden. The basket and all of the artifacts recovered from the site are now displayed and maintained at the BLM Anasazi Heritage Center in Dolores.
Long-range plans for the site include leaving it exposed, installing interpretive signage, and constructing a viewing platform to allow visitors to look down into the site. Among the features visitors will see are three hearths. Spatially they sit close together, but temporally they are separated by centuries, dating back 9,000, 8,000 and 7,000 years, said Hadden.
A final report due to be released soon and Hadden is writing a book on the site, which will be published by Southern Methodist University.