POSTED: 01/01/0001

Download photos from the excavation site.

Significance of the Discovery

  • The Snowmass Village site is one of the most significant fossil discoveries in Colorado history.
  • This discovery is very unique because there are no known sites in Colorado, and few in North America, that contain both mammoth and mastodon fossils in one location.
  • The juvenile Columbian mammoth that was first uncovered in October appears to be the most complete mammoth fossil found at high elevation (8,870 feet) in Colorado. It is also the highest elevation at which mastodons and giant ground sloths have been found in Colorado.
  • Not including the finds made in Snowmass Village, there have been 103 mammoth discoveries and only three mastodon discoveries on record in Colorado. There have only been four other giant ground sloth discoveries in Colorado.

Discovery & Excavation Timeline

  • Thursday, October 14
    The original discovery of a single juvenile Columbian mammoth was made by Jesse Steele, a Gould Construction Company bulldozer operator working on the expansion of Ziegler Reservoir near Snowmass Village. Steele and project manager Kent Olson unearthed approximately 25 percent of the original mammoth's bones, which were cleaned and put on display in Snowmass Village. Kit Hamby, director of the Snowmass Water and Sanitation District, and his team managed the initial discovery, stabilized the site, and cared for the bones that had been collected to date.
  • Monday, October 25
    The Snowmass Water and Sanitation District voted unanimously to donate the fossils to the Denver Museum of Nature & Science.
  • Wednesday, October 27
    Denver Museum of Nature & Science scientists Kirk Johnson, Ian Miller, and Steve Holen visit the Ziegler Reservoir site. While they are there Kent Olson discovers the remains of a large fossil initially thought to be a second mammoth. On further inspection, this animal was identified as a mastodon.
  • Friday, October 29
    Holen arrived in Snowmass Village to prepare for excavation and tour the site. After evaluating the finds to date, he confirmed discovery of at least three mastodons in addition to the original juvenile Columbian mammoth, plus parts of other undetermined mammoths and/or mastodons.
  • Weekend of October 30 and 31
    More than 1,000 local residents viewed bones on display at the Snowmass Water and Sanitation District offices. Meanwhile, the team of scientists, staff and volunteers from the Museum prepared the site for excavation, which began Tuesday, November 2. The team created a site map which identified the areas where bones had been discovered so far. They took samples of peat and silt from the site which were sent for radiocarbon dating, a process that will take 1-2 weeks. These samples will give scientists a much better idea about the age of the bones preserved at the site. In addition, the advance team set up a grid over the juvenile Columbian mammoth. The grid will guide the excavation crew in digging dig the fossil in a careful and systematic way.
  • Monday, November 1
    Samantha Sands, an educator with the Museum, visited students at Glenwood Springs High School and Carbondale Middle School.  As part of the public outreach and education effort, she showed examples of mammoth and mastodon bones from the dig site and explained how museum scientists will study the area.
  • Tuesday, November 2
    Using hand tools and archaeological techniques supplemented by a small backhoe, the Museum team opened up four of the sites that have produced fossil bone over the last week. Over the course of this first full day of excavation, Dr. Holen and Dr. Ian Miller, curator of paleontology and chair of the Museum's Earth Science Department, determined the order of sites to be excavated and deployed teams to those sites. The field effort focused on recovering the mammoth and mastodon bones, as well as recovering a full assessment of the paleoecology of the site where the animals lived and died. This involved sampling the sediment and the fossils of plants, invertebrates such as insects and clams, and a variety of microscopic fossils.
  • Wednesday, November 3
    Almost immediately after beginning work for the day, field crews uncovered the top of a large skull. Three feet of the specimen were exposed by a bulldozer that clipped the top of the skull. Based on the fact that two mastodon tusks had been discovered nearby, Holen concluded the skull was most likely a mastodon. This amazing discovery was made by Gould employee James Hylton and Museum volunteer Don Brandborg, a graduate of the Museum's Paleontology Certification Program which trains citizen scientists to assist on Museum fossil digs across the region.
  • Thursday, November 4
    The most significant day at the dig site yet. Excavation crews discovered two additional species: a giant ground sloth and a small deer-like animal. Also on Thursday, Museum scientists determined there are two additional mastodons at the dig site after discovering a mastodon tooth and a new leg bone in separate places. The total number of animal species found at the dig site now totals five: Columbian mammoth, American mastodon, Ice Age bison, giant ground sloth, and the deer-like animal.


About the Denver Museum of Nature & Science The Denver Museum of Nature & Science is the Rocky Mountain Region's leading resource for informal science education. A variety of engaging exhibits, discussions and activities help Museum visitors celebrate and understand the natural wonders of Colorado, Earth and the universe. The Museum is located at 2001 Colorado Blvd., Denver, CO, 80205.  To learn more about the Museum, check, or call 303-370-6000.

Many of the Museum's educational programs and exhibits are made possible in part by generous funding from the citizens of the seven-county metro area through the Scientific & Cultural Facilities District.

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