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DINOSAUR NATIONAL MONUMENT —When you work on a deep geologic time scale, you’re bound to be late once in a while. ReBecca Hunt-Foster, the paleontologist for Dinosaur National Monument, pulled her black pickup truck into the visitor center parking lot 15 minutes after our decided meeting time.
She ditched her backpack in front of a Stegosaurus statue, ducked into the visitor center to fill a water bottle, then climbed back in her truck — license plate DINOCHK — to head to a nearby strip of hillside that she calls “the dig.”
Hunt-Foster is the paleontologist for the entire national monument, a high desert outpost with a gradient of ecosystems, shifting from shaggy, sagebrush hills to red desert rocks that spans the Colorado-Utah border. The sprawling 211,000 acres, with one of the most complete geological records in the National Park System, doesn’t seem to faze her — when she worked for the Bureau of Land Management her area covered closer to 3.5 million acres in southern Utah, she said.
JUMP TO: Visiting Dinosaur National Monument
She knows she’ll never get to scrape, brush and drill into most of the roughly 500 sites in Dinosaur that have been identified as containing fossils. She barely makes it out to her own dig two days per week. The rest of the time she’s working on funding applications, organizing volunteer groups, giving talks, working in the museum, reviewing construction plans, attending meetings and hanging out with curious visitor groups.
“Part of my job is to make sure no fossils in the park get hurt, so that can lead to a lot of meetings, a lot of getting pulled in many different directions,” she said. “There’s not as much time to sit at one site and just dig every day, which is what they did at the original quarry.”
In the beginning …
The original quarry was discovered in August 1909 by Earl Douglass, a paleontologist from Pittsburgh who found eight giant tail bones of an Apatosaurus — a Late Jurassic longneck — sticking out of a sandstone slope in what is now the southwestern corner of the monument. Five days after the discovery, Douglass recorded in his journal observing throngs of people arriving from Vernal, Utah, to see the bones for themselves.
“For a time the rocks that had never had the impress of a woman’s foot, and seldom that of a man’s, swarmed with people of all ages,” Douglass wrote on Aug. 22, 1909.
These days the monument draws anywhere from 250,000 to 350,000 visitors per year, a small dip from the monument’s visitorship peak in the mid-’90s, when the monument welcomed closer to 500,000 visitors per year. The monument peaked at 534,274 in 1993, coincidentally — or not — the same year that the “Jurassic Park” movie was released.
Of course, when Douglass wrote about the newly trampled ground back in 1909, he wasn’t accounting for the ancestral tribes that called Dinosaur’s shallow caves and rock overhangs home for hundreds of years prior. Archeological evidence of the Fremont people — a name coined by the researchers who first studied the culture along the Fremont River in Utah — exists throughout the monument, and dates as far back as 200 AD. The Fremont culture’s petroglyphs (carvings and etchings) and pictographs (paintings) can still be viewed from a handful of interpretive trails.
One set of petroglyphs and pictographs, on the wall of a sandstone alcove known as Swelter Shelter, is located just a mile east of the Quarry Wall, where many hundreds of years after the images were etched and inked, Douglass would gawk at the adventurous visitors bused in from Vernal.
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In any case, Douglass’ dinosaur findings catalyzed a 13-year excavation, funded by the Carnegie Museum where Douglass worked, and managed by Douglass himself. In 1915, President Woodrow Wilson established the quarry and its surrounding 80 acres as Dinosaur National Monument.
Andrew Carnegie died four years after the designation and the museum pulled its funding from the excavation. By 1924, excavations ceased at the site, leaving behind a 150-foot-long slab that Douglass insisted remain for the public to marvel at and learn from. That slab was later encased by the Quarry Exhibit Hall, where today visitors can observe — and in some places, even touch — a preserved logjam of Stegosaurus plates, Allosaurus femurs, Camarasaurus vertebrae and 1,500 other fossil bones from 10 dinosaur species.
LEFT: Petroglyphs depicting human figures are visible at McKee Springs in Dinosaur National Monument. (National Park Service photos) RIGHT: Pictographs, or paintings, of human forms from the Fremont culture at Deluge Shelter at the monument.
Part of what makes the Quarry Wall such a great exhibit is the hardened sandstone that holds the fossils in place. Hunt-Foster’s current site, on the other hand, is situated in a thin strip of crumbly gray mudstone.
“This is what a quarry looks like in the beginning,” Hunt-Foster said, gesturing at the barely scratched hillside. “What you get at the Quarry Wall, though, that’s of course, a perfect world. That’s Disneyland over there.”
She took a flathead screwdriver and a cheap paintbrush and started wedging a little black nugget out of the wall. It came loose and she turned it over in her bare hands. “Looks like it actually might be another little Camptosaurus tooth,” she said, brushing dirt off its surface. Or maybe a little toe bone, she mused, then grabbed her water bottle to clean up the tooth or maybe toe.
“Oh, looks like just a piece of bone. See how it’s broken on the bottom part?” she said. “It looks like there used to be more of whatever this was.” Then she lightly shoved it back into the wall where she found it.
ReBecca Hunt-Foster, paleontologist for Dinosaur National Monument, picks at the crumbly hillside at her current excavation site, finding a small fossil fragment. Most of the identified fossil sites in Dinosaur National Monument are in the Morrison rock formation and hold dinosaur fossils from the Late Jurassic period. “It was a good time to be alive, a good time to be a dinosaur,” Hunt-Foster said, of the Late Jurassic period. (Parker Yamasaki, The Colorado Sun)
About half a foot away from the bone fragment was a big white bulb, a larger piece of bone wrapped in some kind of cast.
“My volunteer got a little overzealous about excavating around it,” Hunt-Foster explained, pointing at the covered chunk. “I think they thought they were going to be able to just pop it out, and it turned into a bigger thing. Which is fine, that’s normal. I mean, they are dinosaurs. They have a tendency to become pretty large pretty quickly.”
“The most dangerous species”
In 1955, writer and environmentalist Wallace Stegner published an essay titled “The Marks of Human Passage” in a collection about the environmental and historical importance of Dinosaur National Monument. By that time the monument had grown from its original 80-acre quarry to the over 200,000 acres that it occupies today.
The monument’s current boundaries trace two deep river valleys, the Green and the Yampa, that meet at a midpoint in the park and continue flowing west, forming an upside-down T shape. In the 1950s two dams were being debated as part of the Upper Colorado River Storage Project, one at Echo Park, where the two rivers meet, and the other at Split Mountain farther down the Green.
Stegner’s essay was part of a collection, “This is Dinosaur,” which was delivered to every member of Congress and distributed throughout the West.
“We are the most dangerous species of life on the planet, and every other species, even the earth itself, has cause to fear our power to exterminate,” Stegner wrote. “But we are also the only species which, when it chooses to do so, will go to great effort to save what it might destroy.”
The dams were never built, and the Yampa is the only remaining free-flowing river in the Colorado River system. The Green is dammed upstream, outside the national monument boundary, at Flaming Gorge.
The modern day asteroid: Invasive species
Today the rivers remain a major recreational draw for the monument. Last year, Dinosaur received close to 19,000 applications in the rafting permit’s lottery system. The monument grants only one to four permits per day, depending on the season.
Last year’s applications arrived from people in all 50 states, Washington, D.C., and 10 countries, said Emily Spencer, natural resource specialist for the monument. Spencer, who has worked at Dinosaur for 15 years, has to track these things, because the potential for invasive species hitching a ride into the park (from, say, all 50 states, Washington, D.C., and 10 countries) could have a huge impact on Dinosaur.
Ultimately, people from 27 states and a handful of those countries were granted permits. “All of those people are bringing their gear and equipment from different places with different aquatic flora and fauna,” Spencer said.
This past season, she’s been piloting new detection technology on the rivers, in the hopes that Dinosaur will soon be able to partner with surrounding agencies to tackle the recent, potentially devastating spread of zebra mussels, and other aquatic invasives.
The aquatic management is new to Spencer, and her learning curve has been steep, she said. But invasive species in general have infiltrated her whole career.
One of Spencer’s current land side efforts is eliminating invasive leafy spurges and Russian knapweed through a method called “biological control,” which in this case means collecting insects from Idaho, transporting them to northwestern Colorado, and releasing them along the river.
Last year, Dinosaur National Monument was granted more than half a million dollars from the Inflation Reduction Act to implement a six-year-long biological control strategy. The grant funds necessary travel, equipment and administrative costs for Spencer and her crews to collect four insect species that feed specifically on the invasive plants: flea beetles and stem-boring beetles to eat the leafy spurges, and the gall midge and gall wasp to control the Russian knapweed. The goal is to collect and release 50,000-100,000 insects per year. She also takes groups of volunteers on raft trips to help remove invasive tamarisk along the riverbanks, where they just yank out one plant at a time.
The federal funding for biocontrol started this year and ends in 2030. And the aquatic invasive project that Spencer is helping pilot is in “year one of,” she paused to think about it, “probably forever.”
“We like to say we are a medium-sized park, acreage wise, with a small park staff, but big park complexities,” said Sonya Popelka, interpretation supervisor for the monument. Popelka has been working at Dinosaur since 2012, and has collaborated closely with Spencer on a number of research and outreach projects, including the monument’s International Dark Sky Park designation, which it received in 2019, and an ongoing monarch butterfly migration study.
Spencer’s daily to-do list would tire even the most enthusiastic naturalist, but she doesn’t seem bothered by the scope of her work. Just like Hunt-Foster, she’s acclimated to the fact that many of the projects she starts today, she’ll likely never see the end of.
“Working with the National Park Service, where sites are set aside specifically for their national significance, the scale of that responsibility is pretty grand. It’s also well outside of just the individual,” Popelka said. “It’s constantly thinking about what I am doing in my work today that is making an improvement for somebody else, even when that somebody else might show up 100 years from now.”
Visiting Dinosaur National Monument
There are five entrances to Dinosaur National Monument, two on the Utah side and three on the Colorado side. The most popular entrances are the Quarry entrance, accessed through Jensen, Utah, and the Harpers Corner entrance, near the town of Dinosaur in Colorado. Both the Quarry and Harpers Corner entrances have visitors centers with rangers, maps and educational videos.
Most of the known fossil sites are on the Utah side of the monument, accessed through the Quarry entrance, northeast of Jensen, Utah.
The famous Quarry Wall has the fossils from the Late Jurassic period, preserved in a layer of rock called the Morrison formation. The formation was named after the town of Morrison, just south of Red Rocks amphitheater, where the formation was first described by geologists. The Quarry Wall is part of the Quarry Exhibit Hall, accessed through the Quarry entrance outside of Jensen, Utah.
The monument has one of the oldest and most complete geological records in all of the National Park system.
Dinosaur National Monument was designated as an international Dark Sky Park in April 2019. It became the fifth internationally recognized dark sky place in Colorado, and the 12 in Utah.
Harpers Corner Drive is a 32-mile scenic drive that leaves from the Canyon Visitors Center on the Colorado side of the monument, northeast of the town of Dinosaur, and winds its way above the monument’s deep river canyons. There are several overlooks and picnic areas along the drive, along with three hiking trails.
There are six designated campgrounds in the park, three on the Colorado side, and three on the Utah side. The Green River Campground, accessible from the Quarry entrance in Utah, is the largest of the six with 80 sites, 53 of which can be reserved online, and 27 of which are first-come, first-served. The Gates of Lodore at the north entrance to the monument, is the most remote campground in the park. The nearest Colorado town, Maybell, is about 50 miles east of the campground. It is popular with rafters making their way down the Green River, and rarely ever fills up.
The town of Dinosaur was called Artesia until 1966, when the town changed its name to emphasize its proximity to the monument. The town has a gas station, a motel, a grill and a sandwich shop. For more amenities, Rangely is a 20-minute drive south from the Canyon Visitors Center and has a number of hotel, motel and food options, as well as the Tank Center for Sonic Arts.
The Colorado pikeminnow, bonytail and the razorback sucker are federally listed endangered fish species native to the monument’s rivers. Other species like the roundtail chub, flannelmouth sucker and bluehead sucker are also present and listed as species of concern in Utah and Colorado.
Dinosaur National Monument is on the northeastern side of Dinosaur Diamond National Scenic Byway, a 512-mile scenic driving route through Utah and Colorado that includes nine national parks and monuments. Access the Diamond from I-70 in Grand Junction, or highways 139, 64 or 40 in Colorado.
