Tourists at Red Fleet State Park in Utah are destroying historical artefacts more than 200 million years old by throwing them into a lake.
Park authorities say the famous track site is "deteriorating" due to the impact of humans throwing the giant slabs into a reservoir.
At least ten prehistoric raptor tracks measuring up to 17 inches long are believed to have disappeared over the last six months.
Park manager Josh Hansen said: "It's become quite a big problem. They're just looking to throw rocks off the side.
"What they don't realise is these rocks they're picking up, they're covered in dinosaur tracks," he added.
While this problem is quite alarming, often the people who are doing this have no idea they could be destroying millions of years of history, said Mr Hansen.
Staff are warning tourists that disturbing the rocks could be considered vandalism. A teenager was caught hurling sandstone slabs into the park's 750-acre reservoir.
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Mr Hansen said: "Some of the tracks are very distinct to the layperson but just as many are not.
"That is why it is important to not disturb any rocks at the dinosaur trackway."