Paleontologists say they have discovered the 76-million-year-old footprints of a ceratopsian dinosaur-dominated herd in Dinosaur Provincial Park in Alberta, Canada. The discovery provides the first evidence of mixed-species herding behavior in dinosaurs, similar to how modern wildebeest and zebra travel together on the African plains.
A herd of ceratopsians (Styracosaurus albertensis) accompanied by an ankylosaur (Euplocephalus tutus) walk through an old river channel under the watchful eyes of two tyrannosaurs (Gorgosaurus libratus). Image credit: Julius Csotonyi.
Dinosaur Provincial Park in southern Alberta, Canada, is unquestionably one of the premier localities worldwide for understanding Late Cretaceous terrestrial ecosystems.
The Park has yielded hundreds of dinosaur skeletons and huge numbers of bones and teeth, making it a model system for understanding dinosaur evolution, behavior, biostratigraphy, and paleoecology.
Despite the remarkable abundance of skeletal elements, dinosaur footprints and trackways are surprisingly rare.
“In 2024, we discovered a new tracksite, the Skyline Tracksite comprising ‘typical’ natural mould tracks, which had heretofore not been identified in the Park,” said University of New England’s Dr. Phil Bell and colleagues.
At the site, the paleontologists unearthed 13 ceratopsian (horned dinosaur) tracks from at least five animals walking side by side, with a probable ankylosaurid (armored dinosaur) walking in the midst of the others.
They were also surprised to find the tracks of two large tyrannosaurs walking side-by-side and perpendicular to the herd, raising the prospect that the multispecies herding may have been a defence strategy against common apex predators. One footprint of a small meat-eating dinosaur was also discovered.
Views of the Skyline Tracksite shortly after discovery (A) and following excavation (B). Image credit: Bell et al., doi: 10.1371/journal.pone.0324913.
“I’ve collected dinosaur bones in Dinosaur Provincial Park for nearly 20 years, but I’d never given footprints much thought,” Dr. Bell said.
“This rim of rock had the look of mud that had been squelched out between your toes, and I was immediately intrigued.”
“The tyrannosaur tracks give the sense that they were really eyeing up the herd, which is a pretty chilling thought, but we don’t know for certain whether they actually crossed paths.”
“It was incredibly exciting to be walking in the footsteps of dinosaurs 76 million years after they laid them down,” said Dr. Brian Pickles from the University of Reading.
“Using the new search images for these footprints, we have been able to discover several more tracksites within the varied terrain of the Park, which I am sure will tell us even more about how these fascinating creatures interacted with each other and behaved in their natural environment.”
“This discovery shows just how much there is still to uncover in dinosaur paleontology,” said Royal Tyrrell Museum of Palaeontology’s Dr. Caleb Brown.
“Dinosaur Park is one of the best understood dinosaur assemblages globally, with more than a century of intense collection and study, but it is only now that we are getting a sense for its full potential for dinosaur trackways.”
The discovery is described in a paper in the journal PLoS ONE.
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P.R. Bell et al. 2025. A ceratopsid-dominated tracksite from the Dinosaur Park Formation (Campanian) at Dinosaur Provincial Park, Alberta, Canada. PLoS One 20 (7): e0324913; doi: 10.1371/journal.pone.0324913