Ancient cave in Wyoming holds Ice Age secrets including animals long extinct Cave Geology Buckrail - Jackson Hole, news
There is only one way in Natural Trap Cave—get ready to rappel. (GJH)

JACKSON HOLE, WYO – The way John Guslander, a board member of Geologists of Jackson Hole, began this tease couldn’t be more intriguing. We’re borrowing it here:

John Guslander

We have all had that experience of walking around a corner and facing something unpleasant, or picking up the phone to hear bad news. For some animals, that experience happened at Natural Trap Cave on the west side of the Big Horn Mountains. One minute they were running along the ground, the next minute they were falling to their death at the bottom of a deep cave. Their misfortune is our gift.

The mound of animals lying at the bottom of the cave takes us back to a time before humans entered North America. A time when cheetahs and camels lived here. These animals had survived many ice ages but they did not survive us.

Come hear Gretchen Hurley describe the exhumation of their well-preserved remains. And watch where you walk.

Hurley will lead the discussion at Teton County Library on Tuesday, October 3, 6pm, as she presents “Natural Trap Cave: A window into Wyoming’s past.” Hurley is a geologist for the Bureau of Land Management, out of the Cody office.

What is Natural Trap Cave?

To gain access after nearly four decades of dormancy, geologists first had to remove grate put in place by BLM to protect the site from poachers or the clumsy. (GJH)

Natural Trap Cave in the Big Horn Mountains offers unparalleled insights into the Wyoming of the late Pleistocene, of animal life that frequented our state but in many instances is now long extinct.

The cave is a 15-foot wide by 90-foot deep vertical opening that formed in ancient limestones uplifted during formation off the northern Bighorn Mountains over millions of years. During the Pleistocene Epoch and continuing into the Holocene, numerous different species and specimens of Ice Age mammals fell into this cave, typically died on impact, and were beautifully preserved, almost as though they were refrigerated.

Most of the mammals trapped in this cave are extinct now, including the American Cheetah, American Lion, Columbian Mammoth, Short-faced Bear, Beringian Wolf, Bison, Camels, Musk-Ox, and several types of Ice Age horses. But several of the species found in this cave are still living in the area today, including modern pronghorn, rodents, coyotes, fox, and bighorn sheep, among others.

This extremely rare collection of preserved Ice Age fauna is providing researchers a unique look at Ice Age ecosystems and paleoclimates, as well as allowing refinement of information on Pleistocene mammalian DNA and evolution during a critical time in the history of our planet.

Paleontological excavations in this treasure trove were first conducted between the late 1970’s through the late 1980’s, revealing a wealth of excellent data on mammalian taxa living in Wyoming during Pleistocene time. After this research concluded, the cave was closed and gated by the BLM’s Cody Field office for 34 years between 1989 and 2014.

Then, for four summers between 2014 and 2017, Natural Trap Cave was reopened to allow paleontologists Dr. Julie Meachan (Univ. of Des Moines, Iowa), and Dr. Alan Cooper (University of Adelaide, Center for Ancient DNA) and their teams to excavate specimens for a broad range of scientific study.

Entry into the cave was only possible using single rope technique, which was overseen by the researchers and a skilled team of volunteer cavers from area grottos. The recent research project in Natural Trap Cave is managed by BLM geologist Gretchen Hurley of the Cody Field Office.