Sign up to see the mammoth being unearthed near Kennewick. More bones to be dug up

Students visit the Coyote Canyon Mammoth Site, where the bones of a mammoth that lived about 17,500 years ago are being unearthed.
Students visit the Coyote Canyon Mammoth Site, where the bones of a mammoth that lived about 17,500 years ago are being unearthed. Courtesy Pasco School District

A new dig season to unearth more bones of the mammoth found near Kennewick has started, and you’re invited to visit.

Volunteers at the Coyote Canyon Mammoth Site are expecting to make some interesting finds this year.

One of the squares on the grid marked off over the site has bones showing. Digging planned at that square, called Unit 3, may well yield vertebrae and ribs.

If you’d like a first-hand look at the work, registration has opened online for public tours offered April 14, May 12, June 9, July 14, Aug. 18, Sept. 8 and Oct. 13. Go to bit.ly/McBonesTour.

Participants will be emailed directions to the tour site, which is at an undisclosed location to prevent vandalism.

The tour includes a presentation about the mammoth and how it may have come to rest near the Tri-Cities, a look inside the small museum area near the dig site and a visit to the dig site.

The gender of the mammoth will not be definitively determined unless its pelvis is unearthed. But the mammoth appears to be a male, because bone growth plates take longer to fuse in males. The animal likely was about 40 years old when it died with a front leg growth plate still unfused.

volunteer with rib
Neil Mara, a volunteer, holds a drawer that has a mammoth rib that was found at the excavating site at Coyote Canyon Mammoth. File Tri-City Herald

Evidence is mounting that fits the working hypothesis that the mammoth drowned, said Gary Kleinknecht, a retired Kamiakin High teacher and the volunteer who serves as the education director for the project.

“This is a detective job,” he said.

Radiocarbon dating shows the animal lived at the time that ice age floods were roaring through the Mid-Columbia, which could have been from as long as 19,000 years ago to as recently as 14,0000 years ago, Kleinknecht said. The bones are about 17,450 years old.

The flood water backed up as it hit the narrow Wallula Gap to cover what is now the Tri-Cities. The dig site is at an elevation of about 1,060 feet, and floods may have been deep enough to reach the area about seven times.

The mammoth could have been drowned in the flood, and then the carcass could have been deposited on the hillside as waters receded. The bones have been found relatively intact — the ribs somewhat jumbled, for example, but not scattered over a wide area.

Among the bones are rocks, such as granite, not typically found in the Mid-Columbia. It has basalt from lava flows. The non-native granite likely was deposited as the ice rafts that carried the rock during the floods melted.

detail shot
The bones of a mammoth that lived 17,500 years ago are being slowly and carefully excavated by volunteers from a site near Kennewick. File Tri-City Herald

If the cranium and tusk can be found and are lower than the bones of the body, that would add to the evidence supporting the hypothesis that the animal drowned. It likely would have floated in the water with the head down.

Excavation began about eight years, and Kleinknecht estimates it will continue for another five to six years before all the bones are recovered.

Volunteers are still hoping to find the rear legs, pelvis, the cranium, tusks and more of the ribs and vertebrae. Among the largest finds so far are the shoulder blade and two upper front leg bones, plus multiple ribs and vertebrae and some smaller foot and tail bones.

The project is looking for volunteers who can make a regular commitment of time as dirt is carefully scraped and brushed away at the dig site and then put through fine screens.

As volunteers unearth the mammoth’s bones, researchers are conducting a paleoecological study.

Any evidence found as the dirt is screened — such as the remnants of snakes, mollusks, lizards and ground squirrels — is cataloged. It will be used to understand the Mid-Columbia’s climate through the centuries, based on the species that lived here.

Some volunteers may have particular skills that are needed at times, such as mechanical or artistic skills, but most usually start at the bottom as support staff to diggers, handing them tools and carrying buckets of dirt to the screens, and work up from there to tasks that require more finesse.

Digging is done two weekends a month, usually from March through October.

The foundation also is ready to launch a docent program and is looking for its first volunteers to help during tours, Kleinknecht said.

Docents are needed to help not only with monthly tours, but on the many other days that the site plays host to classroom field trips and visits by other groups.

For more information about volunteering, call Kleinknecht at 509-627-1654.

The Coyote Canyon Mammoth Site is a community excavation project in south Kennewick. Watch this video to find out more.

Annette Cary: 509-582-1533, @HanfordNews