More than 18,000 fossilized dinosaur tracks have been uncovered in central Bolivia, making it the most extensive site of its kind ever documented. The discovery, made in Torotoro National Park at a location called Carreras Pampa, sheds new light on how dinosaurs lived and moved through their environment.
The findings include a mix of footprints left on land and rare swim tracks, offering scientists a rare window into dinosaur behavior on both solid ground and in shallow water. The area, which covers roughly 80,000 square feet, was once a shoreline, and many of the footprints still align with the natural ripple patterns in the ancient sediment.
Though the site had been previously noted by scientists, its full extent was only revealed recently after researchers conducted a detailed analysis. Their work, published in the journal PLOS One, identifies more than 16,000 footprints left by carnivorous dinosaurs and over 1,300 swim tracks — more than have ever been recorded at any other site globally.
Rare insights into prehistoric movement
The variety and number of tracks offer a glimpse into how different dinosaur species behaved. Some walked or ran across the land, while others appeared to swim or drag their tails along the muddy surface. Some trackways run in parallel, leading scientists to believe that certain dinosaurs may have moved in groups.
Jeremy McLarty, a paleontologist from Southwestern Adventist University in Texas, said the site is not only the largest of its kind but also contains more swimming traces than any other known location. According to McLarty, these swim marks are especially rare because they capture the motion of dinosaurs as they moved through water — a behavior not often preserved in fossil records.
Many of the swim marks appear as long grooves. These are believed to have been made when a dinosaur’s toes scratched the surface of a shallow body of water. Some tracks show alternating left and right foot patterns, suggesting controlled swimming motion, which provides a unique look at how dinosaurs navigated aquatic environments.
Footprints reveal a range of dinosaur sizes
The tracks at Carreras Pampa come in a wide range of sizes, suggesting the presence of both small and mid-sized predators. Some footprints measure less than 4 inches, possibly made by smaller dinosaurs or younger individuals. Larger prints, exceeding 12 inches, may have been left by carnivores similar to Dilophosaurus or Allosaurus.
Unlike more famous dinosaurs such as Tyrannosaurus rex — whose footprints are typically larger — these mid-sized track makers likely played key roles in their ecosystem. The discovery of smaller prints also helps scientists understand the diversity of dinosaur species that once lived in the region.
The site has been carefully excavated by clearing rocks and sediment, revealing the well-preserved tracks underneath. The natural layout of the prints and ripple patterns in the sediment help confirm the shoreline environment where these ancient creatures once roamed.
Bolivia’s growing role in paleontology
Bolivia has long been recognized for its fossil-rich landscapes. The country is home to another major site at Cal Orck’o, which holds the second-largest collection of dinosaur footprints. However, Cal Orck’o is set along a steep rock face, limiting access and study.
In contrast, Carreras Pampa’s flat terrain offers easier exploration and more detailed analysis. With this new discovery, Bolivia’s role in paleontological research continues to expand, highlighting its importance in the global understanding of prehistoric life.