There’s a long-running debate in Colorado archaeology and biology circles about how long we’ve enjoyed the charismatic presence of moose in our wild lands.
Did the built-from-parts beasts first show up when Colorado Parks and Wildlife brought 24 from Wyoming and Utah in 1978?
Or was that a “reintroduction” of the gawky mammal that had actually roamed this part of the southern Rockies in ancient times before getting hunted and hounded out?
There aren’t many old moose bones around to hit with a carbon dating test and easily answer the question. So a new study led by University of Colorado archaeologists in Boulder is getting a lot of attention for combining what few bones there are with tribal oral traditions, historical records like old newspaper photos, and sources like contemporary journals and photos.
Their conclusion? Moose were in Colorado for hundreds of years before 1978, and there’s a good argument that should include thousands of years before that, to the Early Holocene era, as ice sheets retreated north.
For years, debaters “have sort of struggled to understand that we don’t have a quantitatively useful record of moose. What we have is a complex and interesting record that can tell us some things, but not others, and we have to be very careful with it,” said William Taylor, an associate professor and curator of archaeology at CU Boulder.
With those caveats, though, Taylor is comfortable declaring a rich Colorado moose history with coauthors in June’s Journal of Biogeography.
“Moose were a part of Colorado’s ancient fauna, and are not invasive,” their paper boldly states. “Our review of the paleontological, archaeological, historic, and Indigenous records provides evidence that, prior to the 1978 reintroduction, moose were present and had established populations in the southern Rockies during the 19th and 20th centuries, and likely long before.”
The discussion is more than just, sorry, academic. Moose have proliferated so much in Colorado since that 1970s shipment that some areas like Rocky Mountain National Park believe they may be impacting local ecology in a bad way. Thriving moose and elk are eating the young willows that beavers need to build dams and flood meadows for biologically important wetlands habitat. The park fears the overgrazing by the big mammals results in more grassland and fewer flooded areas that help with ecological diversity and wildland firefighting.
RMNP has talked about fencing or even culling the moose population, the archaeologists note. But if they accept that moose are not invasive newcomers, but a worthy part of ancient southern Rockies ecology, they might make different decisions, Taylor said.
“Our analysis suggests that valid knowledge held by earlier scientists, who were more familiar with the 19th and early 20th century presence of moose in Colorado, has since faded or been displaced, repositioning moose from returning natives to ecological outsiders,” the study says.
The study defines the southern Rockies as “bounded by the Green and Colorado rivers on the west and the Great Plains to the east, and separated from the central Rocky Mountains by Wyoming’s South Pass and Red Desert.” In elevations and ecological zones varying widely from 5,000 feet to over 14,000 feet, the authors cite recent counts showing the Colorado moose population has grown from a few dozen at introduction to 3,500 animals.
Moose bones are hard to find
Pinpointing moose purely through archaeology is a major challenge, Taylor said in an interview. Radiocarbon dating is often a useful tool for dating ancient animals, Taylor said, and got even more accurate after World War II atomic activity put so much more unstable, rapidly deteriorating matter into the environment that is easy to track. Any item that contains once-living matter can be analyzed, sometimes with stunning precision.
“I have a friend who did a project dating rock concert T-shirts down to six months,” Taylor said.
But to radiocarbon date to test for the presence of moose, you need bones.
“Moose remains anywhere on the continent are extraordinarily rare,” he said.
The paper’s authors compared the archeological record of Colorado with that of Alaska, where researchers have noted hundreds of thousands of animal bones in published sources. In one earlier survey, only nine sites in the state mentioned moose, and at some of those sites, less than a tenth of 1% of the bones “are actually moose,” Taylor said.
“Even in places like Alaska, where we know moose were established and for quite a long time, we’re not talking about a one to one correlation” of moose being present on the landscape and showing up in archaeological sites, Taylor said. “We’re talking about moments, accidents, both of preservation, when moose were there, and when they happen to end up in the right pile of bones.”
Reasons include the lower frequency of cultures hunting moose on the scale of, say, bison or deer or elk, Taylor said. Some moose may only be found later if, say, someone used a strong moose bone as a tool, or kept it for another purpose, such as craft or ceremony.
Some moose samples may be widely scattered in tribal records and artifacts, say if a tribe used a strong moose bone as a tool handle or kept a memento for a ceremony or craft purpose.
“The park and others have sort of struggled to understand that we don’t have a quantitatively useful record of moose. What we have is a complex and interesting record that can tell us some things, but not others, and we have to be very careful with it,” Taylor said.
That extra care for researchers means seeking permission and diving into tribal archaeological collections, studying Native American artwork and storytelling for depictions of moose in various geographies from defined historical periods, and from the newspapers and oral history interviews on record from the 1800s onward. Each cache of information turned up multiple contemporary references to established local moose populations in Colorado.
Taylor hopes the paper’s publication serves in part as a callout to historians and archaeologists from tribes to academia, who might offer up more puzzle pieces from their collections. There is an equally uneven record of common species like the mountain goat that are sometimes deemed invasive, Taylor said, and that species is another one ripe for a multidisciplinary archaeological survey.
“When we have a curiosity about what we don’t know that we don’t know, it’s sometimes really striking what the records — the things that trickle through the centuries — actually tell us,” Taylor said.