Thursday, 27 November 2025

THE BULL CANYON TRACKSITE OF EASTERN UTAH

Darrin Mottler's Human to Theropod Comparison
The wind always arrives first.

It sweeps across the red cliffs of eastern Utah, brushing your shoulders like a quiet invitation as you step out onto the stone. 

The La Sal Mountains rise blue and snow-dusted on the horizon—silent, ancient witnesses. 

At your feet, the sandstone is warm, sun-baked, and patterned with bowls and dimples that look, at first, like the aftermath of a rainstorm.

But then you kneel.

You place your hand inside one of the indentations—fingers spreading to follow the outline—and suddenly time collapses. 

Your palm disappears into a footprint three times the size of your own, pressed into this rock nearly 190 million years ago by a three-toed dinosaur striding across a muddy lakeshore. 

The warmth of the desert stone meets your fingers and presses against the cool, deep sensation of time.

This is Bull Canyon Tracksite, one of Utah’s most awe-inspiring windows into the Jurassic.

Bull Canyon lies on the western flank of the La Sal Mountains, within a rugged plateau of red Wingate and Navajo sandstone. The site preserves an astonishing spread of footprints left by Early Jurassic theropods—light, agile, meat-eating dinosaurs with talons and hollow bones, the forerunners of modern birds.

Dinosaur Track, Bull Canyon, Utah
The tracks rest within the Glen Canyon Group formations, sediments laid down along the shifting margins of a prehistoric playa lake system. 

Here, mudflats dried and cracked under the sun, then were wetted again by brief storms—an ideal condition for holding tracks long enough to be buried by the next layer of sand.

Among the most distinctive ichnotaxa present are:

  • Grallator – small, delicate three-toed prints often linked to slender theropods.
  • Eubrontes – larger, deeper, more robust prints associated with big-bodied carnivores like Dilophosaurus.
  • Occasional ornithischian tracks, including possible Anomoepus prints, representing small herbivorous dinosaurs moving across the same shoreline.

Dinosaur Track, Bull Canyon, Utah
Standing before them, the sandstone seems alive with movement. Each footprint shows a frozen splash of action: the slip of a claw, the twist of a heel, the moment a predator shifted its weight.

Every print reveals insights. Some trackways show animals striding with long, confident steps—suggesting a loping, ground-covering gait. Others are tight and compact, indicating slower or more cautious movement.

Parallel trackways record two or more animals moving in the same direction at the same time—possible group travel, or predators trailing prey.

A few prints deform the underlying sediment, proof that the ground was saturated with water. Others preserve delicate claw tips, showing firmer, drying mud. These shifts map out rapid climate cycles in Early Jurassic Utah.

It’s a moment-by-moment account of life—written in the most ephemeral of materials. 

So why does eastern Utah have so many dinosaur tracks? The region around Moab and the La Sal foothills is a world-class dinosaur track corridor with many elements at play.

  • Jurassic climate: alternating wet and dry periods created perfect track-preservation conditions.
  • Basins & playas: low-lying flats captured footprints from multiple dinosaur species.
  • Rapid burial: shifting dunes and lake sediments quickly sealed impressions.
  • Erosion today: modern uplift and weathering have brought these ancient surfaces back to light.

Bull Canyon is one of the most accessible of the sites, offering broad paleosurface exposures ideal for study and public viewing. If you visit at sunrise, the low light throws shadows into the footprints. The tracks seem to deepen, their edges turning crisp like the outline of a freshly pressed print. 

Photo Credit: All photos shown here are by the deeply awesome Darrin Mottler, who generously shared them with me and introduced me to the site. Appreciate you, Darrin!