Capturing History in the Beach Ridges of Cape Krusenstern
In the far corner of northwestern Alaska, Cape Krusenstern National Monument stands testament to human adaptations to climate change for almost 5,000 years.
Around 5,000 years ago, beach ridges began to form along the north coast of Kotzebue Sound in northwest Alaska. Changing environmental conditions, including wind and wave direction, affected coastline formation. For example, summer storms would erode the ridges formed during calmer periods. The beach ridges themselves are therefore a record of storms, wind, and wave direction. Not long after the beach ridges started developing, people who used this newly formed land were leaving behind a record of their own. Today, archeologists study what these people left behind – their houses, tools, and food scraps, among other things – to discover how past Arctic inhabitants adapted to their own changing climate.
Lifeways of the beach residents changed over time. People of the Denbigh (2500-800 B.C.) and Choris (800-300 B.C.) cultures visited the beaches only briefly, perhaps for a few days or weeks, to camp and hunt caribou. Ipiutak people (A.D. 200-800) were more permanent residents. Archeological remains indicate that they built both summer tents and winter houses here. Members of the Western Thule (A.D. 1000-1400) and Kotzebue (A.D. 1400-1700) cultures also built houses to keep them warm during the long winter. The houses at Cape Krusenstern were constructed by first digging a large hole in the gravel beach so the dwelling was at least partly underground. Wood was used to build a frame that could hold animal skins, sod, or gravel in place to create walls and a roof. House shape, size, and other construction details varied over time.
Researchers use archeological evidence from Cape Krusenstern to test hypotheses of how past climate change affected the people who lived here. For instance, it is known that people’s diets changed through time. It is as yet unclear how, and to what extent, changes in climate influenced these dietary changes. By analyzing animal bones left behind by past people’s meals, archeologists hope to discover if, for instance, an increase in caribou hunting 1,000 years ago was caused by changes in sea ice cover and access to marine mammals.
When people’s hunting patterns or technologies change, so too might other activities. The beach ridges of Cape Krusenstern could not provide everything needed to live. People would travel throughout northwest Alaska to acquire stone for tool making, different animal resources, and clay for making pottery. Sometimes, instead of getting the items themselves, people would trade for what they needed. Summer trade fairs in the region are well known from historic sources. Recent archeological research involved analysis of the pottery of regional sites, including Cape Krusenstern. Distinct geographic trends in clay material sources and decoration types provide evidence for exchange networks extending into ancient times. Obsidian tools from Cape Krusenstern have chemical signatures linking them to a source on the Koyukuk River over 200 miles away. People may have traveled there from the coast, but also would have likely traded for obsidian raw material and/or finished tools.
As the climate changed and beaches built up and eroded away, people continued to live at Cape Krusenstern. Results of recent research show that though occupation density varied, habitation over the last 2,000 years was nearly continuous on this part of the Arctic coast. Modern Inupiaq Eskimo people continue to use Cape Krusenstern and the surrounding area to camp, hunt, fish, and gather berries and other plants. This continuity illustrates the resiliency of Inupiaq people and their ancestors, particularly their ability to survive changing conditions in an already difficult environment.
As the climate continues to change today, erosion rates along Alaskan coasts will likely accelerate, affecting Native peoples’ activities and the archeological record of those same activities long ago. The beach ridges are susceptible to coastal erosion, rising sea level, and slumping due to thawing permafrost. Such changes to the landscape are especially damaging to archeological resources, including the cultural history and scientific data associated with ancient sites. Archeologists and other scientists are trying to document as much as they can, but cannot record everything. Inevitably, information will be lost. But we know landscape changes have happened in the past, and people still flourished here. Whatever happens, the Cape Krusenstern beach ridges landscape will record these changes in the coastal environment and culture — as well as any future changes — just as they have recorded them over the past 5,000 years.
Shelby Anderson, Cape Krusenstern Human-Environmental Dynamics Project- Two Hundred Years: on the beach of their time, Department of Anthropology, University of Washington/National Park Service: 2008.
Shelby L. Anderson and Adam K. Freeburg, “A High-Resolution Chronology for the Cape Krusenstern Site Complex, Northwest Alaska,” Arctic Anthropology 2013, 50(1):49-71.
Shelby Anderson and Adam Freeburg, “High Latitude Coastal Settlement Patterns: Cape Krusenstern, Alaska,” Journal of Island and Coastal Archaeology (in press).
Adam Freeburg and Shelby Anderson, Human-Environmental Dynamics at Cape Krusenstern. Final Report for Task Agreement J8W07070032. On file with the National Park Service, Anchorage, AK.
J. L. Giddings and D.D Anderson, Beach Ridge Archaeology of Cape Krusenstern. National Park Service, Publications in Archaeology No. 20, U.S. Department of the Interior, Washington, D. C.: 1986 ed.
Caroline Jezierski, Rachel Loehman, and Amanda Schramm, Understanding the Science of Climate Change: Talking points - impacts to Alaska Boreal and Arctic. Natural Resource Report NPS/NRPC/NRR, National Park Service: 2010.
J. W. Jordan and O.K. Mason, "A 5000 Year Record of Intertidal Peat Stratigraphy and Sea Level Change from Northwest Alaska," Quaternary International 1999, 60:37-47.
Jim Lawler and Sara Wesser, Climate Change Resource Brief for the Arctic Network: Bering Land Bridge National Preserve, Cape Krusenstern National Monument, Noatak National Preserve, Kobuk Valley National Preserve, and Gates of the Arctic National Park and Preserve, National Park Service, Alaska Region Inventory and Monitoring Program, 2010: 1-2.
Owen K. Mason and S. Craig Gerlach, “Chukchi Hotspots, Paleo-Polynas, and Caribou Crashes: Climatic and Ecological Dimensions of North Alaska Prehistory," Arctic Anthropology vol. 32, no. 1, 1995: 101-130.