Perfiles en la Ciencia

Craig Lee: Ice patch archaeologist

Did you know that the four warmest years on record occurred between 2010 and 2015? With warming temperatures, artifacts have been melting out of icy areas on ancestral Native American lands at alarming rates. Once exposed, these objects that have been kept in cold storage thousands of years are at risk of decay and theft, sending Dr. Craig Lee and other ice patch archaeologists on a mission to recover these cultural resources before they are lost forever.

Plants, pollen, animal dung, animal remains, human tools, even human bodies – these traces of the past 10,000 years help researchers piece together the story of changing ecosystems, past plant and animal life, and human use of high-altitude environments. Icy landscapes around the world have yielded astounding finds, from millennia-old remnants of hunting and traveling in Europe and North America to human remains such as Ötzi the Iceman (Figure 1), a 5,300-year-old mummy discovered in the Tyrolian Alps. The finds in each area paint a picture of the past life and climate of those places, and with the advent of a recent warming period across the globe, the ice is spilling its secrets faster than archaeologists and paleobiologists can keep up with them.

Figure 1: Reconstruction of Ötzi the Iceman by Kennis at the South Tyrol Museum of Archaeology.

image ©South Tyrol Museum of Archaeology/

Artifacts have likely been stumbled upon in alpine areas for centuries, but the ice preserved them so well that they were not always recognized as hailing from the distant past. For example, hunting objects were discovered in the high country of Norway in the first part of the 20th century, but it took decades to make a connection between the appearance of artifacts and warmer temperatures. Even when the link was ventured in a 1937 publication, it was not recognized as a global phenomenon and went largely unnoticed by the worldwide scientific community. Archaeologists took an interest in high altitude environments as artifacts continued to surface in the Norwegian mountains, but the developing field stayed largely confined to Europe. Then nearly 20 years ago, a chance discovery in Canada brought worldwide attention to the budding field of ice patch archaeology in North America (Dixon et al., 2014).

The birth of a new scientific discipline

In September 1997, Kristin Benedek and her husband, biologist Gerry Kuzyk, were hunting sheep in the mountains of the southern Yukon when they came across a huge deposit of caribou dung that had surfaced from a melting ice patch. This was unusual in itself since the area had not seen caribou for at least 70 years. Protruding from the dung was what turned out to be part of an ancient hunting weapon with bits of sinew and feather fletching still attached. Radiocarbon dating showed the throwing-dart to be 4,300 years old. Other artifacts followed, and scientists around the world took note that ice patches in North America were surrendering evidence of past human activity. This launched the Yukon Ice Patch Project, which has partnerships with six First Nations tribes in whose traditional territory the ice fields are found – Champagne and Aishihik, Kluane, Carcross/Tagish, Kwanlin Dun, Ta'an Kwach'an, and Teslin Tlingit – and marked the beginning of ice patch archaeology as an active field of study in North America (Hare, 2011). In addition to explorations in Alaska and Canada, ice patch archaeology projects have now been conducted in the Rocky Mountains, the Greater Yellowstone Area, Olympic National Park, and Glacier National Park.

As opposed to what we typically think of as archaeologists’ work, i.e., digging with a trowel in a small area, ice patch archaeologists generally look for items melting out of the surface of an ice patch as it retreats, or in areas recently exposed by melting ice. These rugged researchers travel by truck, plane, helicopter, and foot to remote patches of ice in search of traces of the past (Figure 2).

Figure 2: View of ice patches in the Greater Yellowstone Area. Ice patches that hold valuable cultural items are often found in remote areas.

image ©Dr. Craig Lee

One leader in the field of ice patch archaeology in North America is Craig M. Lee of the Institute of Arctic and Alpine Research (INSTAAR) at the University of Colorado, Boulder. Dr. Lee is credited with recovering the oldest intact wooden artifact ever found in an ice patch: a birch dart shaft with personal markings near the tip (Figure 3). The item was found near Yellowstone Park in 2007, and radiocarbon dating showed it to be an astonishing 10,300 years old. The recovery of organic artifacts such as wooden weapons is particularly informative because they reveal far more about how weapons systems operated than chipped stone blades or projectile points alone can. And unlike stone tools, organic finds can be directly dated using the radiocarbon dating technique, thereby giving a more precise estimate to the period of use of other, inorganic finds in the vicinity, helping scientists reconstruct the history of an area.

Figure 3: Dr. Craig M. Lee examining the 10,300 year-old dart he found near Yellowstone National Park. The Colorado Front Range is in the background.

image ©Casey A. Cass / University of Colorado

Science with a sense of urgency

Ice patches are areas at high elevations that never completely thaw. Snow falls every year in these spots, and each summer the top layer usually melts; however, occasionally some remains, compressing the underlying material. There is evidence that permafrost – permanently frozen subsoil – keeps at least some ice patches cold from underneath. This process can encase and preserve thousands of years of history.

Ice patches are different from glaciers. While glaciers move and shift, crushing objects within them, ice patches are very stable and provide natural cold storage for the objects left behind (Figure 4). Thus, whatever ends up dropped on an ice patch becomes trapped under a new layer of snow and ice and remains undisturbed, preserved in a deep freeze for hundreds or thousands of years. That was the case anyway until the biggest thaw in recent history started releasing long-frozen items at an alarming rate (C. Lee, personal communication, August 17, 2016).

Figure 4: Ice patch in the Greater Yellowstone Area. Unlike glaciers, which move and crush objects, ice patches remain stable.

image ©Dr. Craig Lee

According to NOAA, the four warmest years on record occurred between 2010 and 2015. One place where the effects of global warming are clearly evident is Glacier National Park, Montana. Referred to as the ‘poster child’ for losses related to climate change, the park boasted over 150 glaciers when it opened in 1910 but now has only 26 – a full 67 percent reduction (Lee et al., 2014). Perennial ice patches in other parklands and national forests are also melting; these areas are the focus of a large coordinated archaeological project on which Dr. Lee is a principal investigator. Archaeologists feel an ethical obligation to recover cultural resources at risk of being lost, as expressed in National Park Service (NPS) Policy Memo 14-02:

Climate change poses an especially acute problem for managing cultural resources because they are unique and irreplaceable—once lost, they are lost forever…. [T]he decisions we make and the priorities we set today will determine the effectiveness of NPS stewardship of cultural resources in the coming decades. (Jarvis, 2014)

Punto de Comprensión
"Ice patch" is another word for "glacier."

The making of a scientist

Dr. Lee has led field projects in Colorado, Montana, Wyoming, and Alaska. Having grown up in Montana and Colorado, he had some familiarity with the environments he now studies through excursions in his youth with his mother and father. In 1996, he graduated with a bachelor’s degree in Sociology (Anthropology option) from Montana State University. Five years later he earned a master’s degree in Anthropology (Archaeology concentration) from the University of Wyoming.

As with many successful scientists, Lee had a mentor to guide him: E. James Dixon, one of the foremost North American archaeologists alive today. Dr. Dixon, whose specialty is high-altitude environments, is a former curator at the Denver Museum of Nature and Science and current director of the Maxwell Museum of Anthropology as well as professor at the University of New Mexico. Lee has worked closely with Dixon over many years, including four summers as field camp instructor at the On-Your-Knees Cave Archaeological Project in Alaska, where Dixon was principal investigator on a decade-long study of human remains found there that were dated at 9,730-9,880 years BP, making them the oldest found in Alaska or Canada at the time. (In radiocarbon dating, age is expressed in years “before present,” or BP, where “present” is considered 1950 CE.) The project was celebrated for enhancing relationships with Native tribes (Heaton, 2002).

While Dixon was a professor at the University of Colorado, he encouraged Lee to pursue a PhD there. The two have collaborated on several published articles and professional presentations, and they are still in very close contact. “He has been a mentor in every sense of the word,” Lee says (personal communication, 2016). (Read about the influence of mentoring and collaboration in our module Scientists and the Scientific Community.)

Lee enjoys the mountain landscapes and lives in the area he studies. He serves on the Board of Directors of the Lamb Spring Archaeological Preserve (Colorado) and the PaleoCultural Research Group (Colorado) and is a past-President of the Montana Archaeological Society. After spending the 2011-2112 school year in his hometown of Bozeman as a visiting assistant professor at Montana State University, he decided to stay. He dedicates late summer/early fall to fieldwork but teaches part-time at Montana State University in the spring while keeping in touch with the INSTAAR lab at the University of Colorado.

A sharing of ideas

Like his mentor, Lee emphasizes open communication as a guiding principle of his own investigations. Throughout history, alpine areas have been used by Native Americans for hunting, spiritual quests, retreat, and the gathering of plants and minerals (Reckin, 2013). (See an animation from the Glacier National Park Ice Patch Project of an Elk Hunt for more details.) The oral traditions of Native peoples support these uses, and with warming temperatures, physical traces of this history are rapidly emerging from the ice. Just as the archaeological investigations at On-Your-Knees Cave enjoyed a spirit of collaboration with Tlingit and Haida Native groups, and the integration of their ideas into the research, Lee acknowledges tribal members as key stakeholders in projects that take place on their ancestral lands and underscores the importance of ongoing dialogue with Native people during field investigations. Both Dixon and Lee have been recognized for building cooperative partnerships between research scientists, US government entities, and tribal governments (University of Colorado, 2007). Ira Matt of the Confederated Salish and Kootenai Tribes of the Flathead Reservation says, “I think it’s a good step…to start to bring in the people’s voice of those that are being studied, and so I think it’s really important that the elders are able to have a voice in what’s said.” (National Park Service video, 2014).

Lee enlisted the help of Shane Doyle (Figure 5) to serve as a liaison between tribes and researchers. Dr. Doyle is a Crow tribal member who grew up on a reservation. A lifelong member of the Montana Indian Community as well as a singer of Plains Indian music, Doyle has participated in powwows and other ceremonies throughout Indian country for over a quarter of the century and has friends from every tribe. He has worked with Lee and other archaeologists in communicating with various tribal groups in the Greater Yellowstone Area and is particularly instrumental in connecting with people who are difficult to contact through email or mobile phone. Doyle plays a pivotal role in bridging the cultural divide that often exists between scientists who study ancient tribal cultures and contemporary tribal communities themselves.

Figure 5: Dr. Shane Doyle, EdD and member of the Crow Tribe, serves as liaison between tribal members and researchers.

image ©Kelly Gorham / Montana State University

"Craig [Lee] is very respectful of tribal culture and communities," Doyle says (S. Doyle, personal communication, August 26, 2016). "By connecting with Indian people in this way, Craig ensures that the objects he discovers are also well known in Indian country." According to Doyle, "The more archaeologists and anthropologists work in tribal communities and with Indian people, the greater their opportunity to glean insight from the descendants of the very people whom they wish to more deeply understand."

Science and heritage values

Native American culture fosters deep spiritual ties to the land. Not surprisingly, ice patch archaeology on ancestral lands has cast the spotlight on cultural resource management and heritage values, bringing up concerns about how to properly collect, inspect, and protect culturally sensitive objects. Mike Durglo, Sr., of the Confederated Salish and Kootenai Tribes of the Flathead Reservation, calls cultural resources from original tribal lands their “most precious resources” (National Park Service video, 2014).

In the past, pre-contact archaeology in the Americas could be a source of conflict depending on how the tribes involved believed their heritage materials should be handled and interpreted. Lee states:

There’s frequently a disconnect between the material culture of indigenous groups in North America and the archaeologists interested in studying it, because most archaeologists are not of First Nations/indigenous descent. There’s an element or aspect of "colonial archaeology," or the "archaeology of the other" at play.

Among non-archaeologists, the lack of personal investment puts many ancestral objects at greater risk of theft by "treasure hunters," as evidenced by several cases of looting that have made the news, including the taking of spiritually significant artifacts. Lee continues, "People will go artifact hunting and bring home objects to stash in their drawer for their own personal enjoyment as opposed to sharing the materials with the descendants of the cultures that created them as well as the rest of the citizens of the United States."

Ice patches in the conterminous United States are invariably found on public lands, so items on those lands are protected by federal laws, in particular by the Archaeological Resources Protection Act and the Native American Graves Protection and Repatriation Act. In a Los Angeles Times interview, Greg Haverstock, a US Bureau of Land Management archaeologist, says that when people help themselves to Native American artifacts, "It damages archaeological records and the shared heritage of our nation. It also impacts tribal members who regard the removal of such items as sacrilegious" (Sahagun, 2015).

On the other side, successful projects throughout North America have seen a true collaboration between tribal representatives and researchers to ensure respectful handling of sacred and otherwise important objects from tribal culture. One such project is the Glacier National Park Ice Patch Archeology and Paleoecology Project, which involved tribal experts at every step. Members of the Confederated Salish and Kootenai Tribes of the Flathead Reservation and the Blackfeet Nation teamed up with the National Park Service, the University of Arizona, the University of Colorado, and the University of Wyoming through the National Park Service’s Cooperative Ecosystem Studies Unit (Rocky Mountains region) to study ice patches in Glacier National Park. The participating groups established a protocol for surveying culturally sensitive areas and handling any objects that might emerge from the ice (National Park Service, 2014). Kootenai tribal member Don Sam (shown in Figure 6) says, “I’d like to dispel the myth that the tribes are a roadblock; we’re actually contributing – and capable and competent” (National Park Service video, 2014).

Figure 6: Don Sam of the Kootenai Tribe heads down a valley in Glacier National Park to investigate an ice patch.

image ©Rachel Reckin

No artifacts were recovered, but the project received a Partnerships in Conservation Award from the Department of the Interior. According to Lee, it was an incredibly successful marriage between tribal interests and archaeological investigation, an out-and-out acknowledgment of climate change, and fruitful as a marketing tool to raise awareness of ice patch archaeology. Further, the team created an aerial photo archive and other materials that will aid future investigations.

The survey area was less conducive to finding archaeological material in the first place due to steeper mountains, greater snow volume, more water flow, and loads of vegetation. In addition, one of the field seasons (2011) was postponed because an epic snow year, which saw a 250% increase in the average snowfall and caused snow depths at the ice patches to thicken inordinately. "While we didn’t find artifacts during our survey, it’s not to say there are none," Lee says.

Punto de Comprensión
In the past, a point of conflict concerning cultural artifacts found on ancestral lands centered on

It takes a village

Ice patch archaeology is by nature a multidisciplinary study that involves archaeologists, paleobiologists, tribal experts, cultural specialists, ecologists, and climatologists who are racing to tell the story of the past before it disappears in the thaw. It takes a whole cadre of scientists to analyze the material gathered for study, including specialists in plants, pollen, insects, and wildlife, among others.

Ice patch projects in North America are coordinated efforts of the US Forest Service, the US National Park Service, tribal groups, and universities. This coordination is key to the success of projects because some ice patches are divided by boundaries of different managing entities. After all, people in the past "certainly weren’t constrained by the political boundaries that exist today," says Lee (Yellowstone NPS video, 2015). One group that has been indispensable to furthering work is the Greater Yellowstone Coordinating Committee (GYCC), a consortium of federal agencies that identifies cross-boundary issues on public lands.

Science doesn’t happen in a vacuum, so just as the openness of communication is fundamental to relationships between researchers and tribal representatives, it is also plain good science. Data sharing with other entities is a must. For example, Lee is keen on exchanging information with other teams who conduct investigations into Greater Yellowstone Area ice patches. He would like to share his methods, thought processes, and procedures for surveying, recording, and analyzing finds so they can be replicated and hopefully made better. (Read more about these hallmarks of scientific inquiry in our module Scientific Ethics.)


The field season for ice patch archaeology is short, from late summer to early fall, and conditions are unpredictable. Investigation may be hampered by any number of unforeseen obstacles: animal encounters, tricky terrain, early snow squalls, forest fires. But by far the biggest obstacle to fieldwork is winter weather since heavy snowfall and thicker ice layers conceal material that may have begun emerging in previous high-melt years.

Given these hurdles, luck and flexibility are major factors in successful data gathering. But in addition to the necessary dose of good luck, ice patch projects require careful planning. Initially, topographical maps augmented by other photographic images were used to identify potential areas to survey. More recently, virtual globes like Google Earth with its high-resolution satellite imagery combined with 3D modeling have helped to refine survey locations. After a winnowing of candidates, the survey team may then take a fixed-wing aircraft to assess ice patches, as the best way to see them is from the air (Figure 7).

Figure 7: Aerial view of the Greater Yellowstone Area. The best way to see ice patches is from the air.

image ©INSTAAR /

The permanent ice patches are then looked at in terms of features that lend themselves to the preservation and recovery of artifacts. Once on the ground, the survey team uses GPS (Global Positioning System) devices, walkie-talkies, and digital cameras. In addition to examining the ice patch itself, the investigators also look for areas of run-off and follow streams in search of materials that might have been carried off from where they melted out, sometimes several hundred meters away. (Lee et al., 2014).

Any new field of investigation requires new methods, tools, and techniques for locating, recording, collecting, and analyzing data. Among these, a modified technique for extracting ice cores was developed by the Glacier National Park team in partnership with the University of Wisconsin, Madison (Figure 8). This was necessary because of the particularly porous and dirty ice found in sub-alpine ice patches (NPS, n.d.).

Figure 8: Craig Lee in the field with the inner barrel of a two-barrel ice coring system known as the Prairie Dog, designed by Jay Kyne and Joe McConnell of the Ice Drilling Design and Operations (IDDO) program based at the University of Wisconsin, Madison.

image ©INSTAAR /

Ice core samples show a cross-sectional view of the history of a region. Many of the things that land in the snow get incorporated into the ice. When a big melt event happens, those materials – be they fecal pellets, leaves, dust, volcanic ash, plant and animal remains, lost tools – start to build up in a thicker layer, forming "lags," or debris-covered ice, that effectively form a barrier between the ice and the atmosphere, which slows down melting. When an ice core is extracted, lags show as dark bands in the sample. The longer the melt period, the thicker the lags. These are separated, melted, dried, and then sampled for paleobiological material. (See a field team drilling an ice core in Figure 9.)

Figure 9: A field team led by Craig Lee and co-principal investigators David McWethy (Montana State University) and Greg Pederson (US Geological Survey) drilling a core from an ice patch in the Greater Yellowstone Area.

image ©INSTAAR /
Punto de Comprensión
The biggest obstacle to field work that ice patch archaeologists may face is

Land "untrammeled by man"?

Ice patches are spread out over a vast expanse of federal lands. One major challenge to study teams is that permission cannot be granted to land a helicopter on some of the ice patches slated for survey. The Wilderness Act, signed into law in 1964, prohibits the landing of aircraft and the use of other forms of mechanical transport on any federal land designated as wilderness, whether it is found in a National Park or on U.S. Forest Service land, so getting to some remote survey areas may require an arduous multi-day hike (Figure 10). The Act seeks to preserve the pristine condition of these areas "where the earth and its community of life are untrammeled by man" (US Congress, 1964).

Figure 10: The Wilderness Act of 1964 prohibits motorized transport on protected lands, so research teams must travel on foot to remote areas that are designated as "wilderness."

image ©INSTAAR /

Lee perceives a paradox:

Ironically, they preserve the best evidence of trammeling around by pre-contact people. Humans were integral parts of the ecosystem. Those who want to preserve a given "park" in an imagined pristine condition are aiming to achieve something that simply does not reflect the historical reality or condition of the parkland.

In fact, archaeological evidence shows that the Clovis people (an ancient Paleo-Indian culture) were in Yellowstone as much as 12,000 years ago, and that the Park was teeming with people by 10,000 years ago. "It’s important that we realize that these are peopled landscapes. We sometimes get so lost in the forest that we miss the trees," says Lee.

Looking forward

In June 2016, Lee traveled to the Principality of Monaco to accept the prestigious Camp Monaco Prize from Prince Albert II. The prize, funded by the Buffalo Bill Historical Center’s Draper Natural History Museum, University of Wyoming’s Biodiversity Institute, and the Prince Albert II of Monaco Foundation-USA, is awarded every three years to groups working to conserve the biodiversity of the Greater Yellowstone Ecosystem (GYE). Lee and his co-recipients David McWethy of Montana State University and Greg Pederson of the US Geological Survey (Figure 11) will use the award to foster greater understanding of environmental change and past human activity at high elevations within the GYE. Lee and his colleagues are looking forward to more involvement of Native peoples in these upcoming research efforts.

Figure 11: His Serene Highness Prince Albert II of Monaco, left, presented the Camp Monaco Prize to Craig Lee, Gregory Pederson (US Geological Survey), and David McWethy (Montana State University), pictured left to right, on June 30, 2016, in Monte Carlo, Monaco.

image ©FPA2, JC Vinaj. Used with permission.

For Lee, the most personally rewarding aspect of his work is “seeing other people getting interested and carrying the torch.” He stresses that it is not strictly a Greater Yellowstone or a Lower 48 (conterminous states) phenomenon, as the ice patches already surveyed here and elsewhere represent only a tiny fraction of those around the world that may hold archaeological and paleobiological materials. Great stretches of alpine landscapes in Europe, Asia, North America, South America, and Asia have yet to be surveyed.

A warming world affects the cultural heritage of groups of people as elements of an unfolding history are in danger of being lost forever. This is a story told in layers, and climate models suggest that there will be no slowing down of the telling in coming decades as warming continues. With the field of ice patch archaeology comes a sense of urgency that keeps researchers on the move so key pieces of the story don’t get lost in the big melt.

Active el resaltado de términos del glosario para identificar fácilmente los términos clave dentro del módulo. Una vez resaltados, puede hacer clic en estos términos para ver sus definiciones.

Active las anotaciones NGSS para identificar fácilmente los estándares NGSS dentro del módulo. Una vez resaltados, puede hacer clic en ellos para ver estos estándares.