A construction project caused damage to 100-million-year-old dinosaur tracks in Utah

A site in Utah containing dinosaur and other animal tracks dating back more than 100 million years was damaged during a recent construction project, the federal Bureau of Land Management recently acknowledged.

A paleontological assessment posted to the bureau's website last week concluded that there had been some minor damage to tracks and trace fossils at the Mill Canyon Dinosaur Tracksite in Moab.

"Unfortunately, little can be done to restore broken or eroded tracks left exposed in situ," BLM paleontologist Brent H. Breithaupt concluded in an assessment.

"In addition, small microfractures may well have formed because of the weight of the machinery on the track-bearing surface. As such, natural degradation may be accelerated in these areas in the future," Breithaupt added.

During the week of Jan. 23, the bureau began work to replace the boardwalk at the roughly 2.3-acre tracksite, which sees thousands of visitors.

The Mill Canyon Dinosaur Tracksite dates to the Early Cretaceous period – roughly 112 million years ago – and contains more than 200 tracks and traces of at least 10 different animals, including several kinds of dinosaurs such as sauropods, ankylosaurs and ornithopods.

In the course of the project, workers drove a backhoe and other construction vehicles over parts of the site that contained tracks, in some cases causing damage, the assessment found.

After locals reported damage at the site and the national media began writing stories, the bureau stopped work on the project on Jan. 31, according to the assessment.

"I'm absolutely outraged that the BLM has apparently destroyed one of the world's most important paleontological resources," Patrick Donnelly, with the Center for Biological Diversity, said at the time.

Breithaupt said in his assessment that the events surrounding the damage to the site were "unfortunate and could have been avoided."

The Bureau of Land Management, in a statement posted to its website after the publication of the assessment on Wednesday, said it was committed to protecting fossils on public lands and that the replacement of the boardwalk was necessary to protect and manage the tracksite.

"To ensure this does not happen again, we will follow the recommendations in the assessment, seek public input, and work with the paleontology community as we collectively move forward on constructing boardwalks at the interpretive site," the statement read.

The bureau said that, before it resumed construction at the site, it would draft a supplemental environmental assessment and seek public comment on it for 30 days. It anticipates reaching a decision this summer.

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