In early 2024, researchers surveying Canada’s Dinosaur Provincial Park uncovered a 29-square-meter patch of mudstone preserving dinosaur footprints not previously recorded in the reserve. The surface lay within an area already noted for 76-million-year-old tracks, yet the fresh find shifted attention from bones to behavior by capturing several species moving in a single herd.
Mapping showed at least five ceratopsians, one ankylosaurid, one small theropod, and two tyrannosaurids, all oriented toward what had been a river margin. The ceratopsian and ankylosaurid prints clustered tightly, while the small carnivore skirted the flank of the group. Two tyrannosaurs walked side-by-side on a path that crossed the herbivores’ line of travel at a right angle, a layout researchers interpreted as a possible ambush.
“The footprints of the tyrannosaurs suggest that they were observing the herd, which is a pretty chilling thought, but we don’t know for certain whether they actually crossed paths,” said Phil Bell of the University of New England.
“It was incredibly exciting to walk on the tracks of dinosaurs 76 million years after they left them,” said Brian Pickles, the University of Reading paleontologist who coordinated the fieldwork.
The team used photogrammetry and thermal surface mapping to gauge print depth and gait length, and published the results in PLOS ONE. They proposed that the herbivores formed a mixed grazing group comparable to modern wildebeest–zebra assemblages, gaining more eyes and bodies to deter predators.
Spatial evidence supported that view. Every herbivore footstep aimed toward water, yet the animals kept a formation that would have limited a direct strike. The muddy impressions “resembled mud that had been squelched out between your toes,” Bell said. Preservation was sharp enough to place the animals on the floodplain within hours of one another, though the team allowed that days could have elapsed between passes.
Horned dinosaurs had long been suspected of living in herds because bone beds often held multiple skeletons. “These bone beds only indicate that these animals died together or their carcasses accumulated after death,” said Jack Luvgrove of London’s Natural History Museum. The new tracksite demonstrated ceratopsians traveling together while alive—and doing so alongside different species.
Caleb Brown of the Royal Tyrrell Museum said the discovery showed how much remains to be learned in dinosaur paleontology.
High-resolution images led Pickles’ team to flag nearby slabs for excavation. Preliminary scouting revealed more multispecies trails resembling the original configuration, suggesting that coordinated movement across the Late Cretaceous floodplain was common. Further analyses aimed to measure individual stride lengths and to test whether the tyrannosaurs’ perpendicular route marked a hunting tactic or a coincidence. Aerial surveys have already detected additional anomalies that may outline an even broader network of trackways beneath the badlands surface.
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