West Side Story

Sampson_ch14.qxd 7/9/09 1:25 PM Page 233 14 WEST SIDE STORY THE WALKIE-TALKIE CRACKLED with the disappointing news, realizing our collective fears. The helicopter had failed to lift the largest block containing the bulk of the duck-billed dinosaur skeleton. Our crews from the Utah Museum of Natural History (UMNH) had spent much of the last two field seasons working more than 3 kilometers (2 miles) from the nearest road, hiking daily through the hilly Utah badlands while carrying tools and supplies—rock saws, hammers, awls, brushes, plaster, burlap, and water—in order to unearth the 75-million-year-old bones. From stem to stern, this plant-eating dinosaur would have been about 11 meters (34 feet) long and weighed about as much as an African elephant. The skeleton’s back end was found with the bones connected as in life. The front end, in contrast, was jumbled prior to burial, likely by flowing water. Although only part of the skull was present and little evidence was found of the legs, this specimen rep- resented the most complete skeleton yet found in Grand Staircase–Escalante National Monument.1 The bones were encased in brutally hard sandstone and spread over too great an area to be removed in a single chunk. So the crew had spent weeks dividing up the specimen into more manageable blocks, each consisting of multiple fossils together with the surrounding rocky matrix. Each received a mummy-like wrapping of plaster and burlap, a protective JACKET that would allow the bones to be safely moved back to the museum. Now the only problem was finding a ride for this dinosaur. Because of the large size of the fossils, dinosaur workers regularly encounter logistical challenges not faced by most paleontologists. Smaller jackets (weighing up to about 25 kilograms, or 55 pounds) are carried by hand or placed into backpacks and walked to 233 Sampson_ch14.qxd 7/9/09 1:25 PM Page 234 the nearest road. Larger specimens up to about 70 kilograms (154 pounds) can be secured to a stretcher and carried out by teams of four or more (an odd practice when one contem- plates “rescuing” animals that have been dead for millions of years). Still heavier specimens (up to about 150 kilograms, or 330 pounds) can be roped down to a large platform— an old car hood used as a sled is often the tool of choice—and dragged over the ground. Occasionally, horsepower in the form of actual horses is brought in to replace humans for these drags. Yet the dragging technique is practical only for short distances. Finally, for remote specimens too large to be carried or dragged, paleontologists commonly resort to helicopter airlifts. Dominated by rugged, sparsely vegetated, and spectacularly beautiful badlands, Grand Staircase–Escalante National Monument encompasses almost 2 million acres of south-central Utah and a vast portion of the greater Four Corners region. Because of its inhospitable terrain, the area now encompassed by the Monument was the last major region within the lower forty-eight United States to be formally mapped. The earliest white settlers (and almost everyone since) elected to circumnavigate this arid, desolate terrain rather than attempt a crossing. For the same reason, Grand Staircase now repre- sents one of the last largely unexplored regions in the United States from a paleontological perspective. In 1996, Bill Clinton signed a Presidential Proclamation designating these fragile, high-desert wildlands a national monument to be administered by the Bureau of Land Management. The Monument was set aside in large part for the preser- vation and study of its diverse natural bounty, both living and fossil. It is surrounded by other public lands; some, like Zion, Bryce Canyon, and Capitol Reef national parks receive millions of visitors each year. In contrast, Grand Staircase retains a strong sense of remoteness and has far fewer visitors, largely because vehicle access to its interior is limited to a smattering of dirt roads. The Monument’s name refers to the staircase-like arrangement of rocks ascending from Grand Canyon National Park in the south to Bryce Canyon National Park in the north. In between is a series of gargantuan steps separated by spectacular, multihued cliffs of chocolate, vermillion, white, gray, and pink. This remarkable geologic sequence provides a localized glimpse of much of the Mesozoic, with Triassicrocks transitioning to Jurassic and then to Cretaceous, all capped by pink cliffs of the early Cenozoic Claron Formation. The three formations highlighted in this book—Chinle, Morrison, and Kaiparowits—occur in the Grand Staircase, although the Kaiparowits Formation only minimally so. A few miles east, however, in the north-central Kaiparowits Plateau region of the Mon- ument, the Kaiparowits Formation is abundantly exposed as gray, cliff-forming badlands. Together with the underlying Wahweap, Straight Cliffs, and Tropic Shale formations, these sediments preserve one of the most continuous records anywhere of the end of the dinosaur era. In 2000, together with Mike Getty of the UMNH,2 I initiated a project to explore these badlands, and the Bureau of Land Management kindly agreed to fund the effort.3 Prior to commencement of our work, most paleontological efforts within the Monument had concentrated on small Cretaceous denizens, particularly rodent-sized 234 • WEST SIDE STORY Sampson_ch14.qxd 7/9/09 1:25 PM Page 235 Grand Staircase – Escalante National Monument UTAH GSENM Kaiparowits Formation LakeLake UTAH PowellPowell ARIZONA 50 Km FIGURE 14.1 Map of Grand Staircase–Escalante National Monument, southern Utah. The dark shaded region depicts the area of greatest exposure of the Late Cretaceous Kaiparowits Formation. Inset depicts scale of the Monument relative to the state of Utah. mammals. Dinosaurs were known, but limited to fragmentary remains, most simply picked from the surface. Were it not for the fact that this place is so inaccessible, the fossil riches of Grand Staircase would likely have been pillaged long ago, and I would have been forced to look elsewhere, likely in less productive sediments. I sometimes find this thought comforting, even inspiring, as I sit quietly and gaze out at the vast tracts of multihued, unexplored badlands. However, on that day, as we tried unsuccessfully to airlift a dinosaur, the thought offered minimal consolation. Several of the hadrosaur blocks we were trying to get out of the Grand Staircase back- country were well within the oversized, helicopter-only category, with the largest jacket roughly estimated at 500 kilograms (1,100 pounds). The National Park Service from nearby Zion National Park had kindly offered their firefighting helicopter and flight crew free of charge to perform the dinosaur extraction. We were extremely thankful and excited by the prospect of getting this beast on the move for the first time in millions of years. Up to this point, everything had gone off according to plan. Prior to airlift day, a mixed Park Service–UMNH crew had hiked out to the excavation site and manhandled the jacketed fossils into large, sturdy nets to which the helicopter lift cable would be attached. Several of our crew members had walked again to the site earlier that morning so that they would be present to attach the cable when the air support arrived. The helicopter arrived on WEST SIDE STORY • 235 Sampson_ch14.qxd 8/24/09 2:03 PM Page 236 FIGURE 14.2 Top: Skeleton of the duck-billed (hadrosaurine) dinosaur Gryposaurus monumentensis in the ground in Grand Staircase–Escalante National Monument. Most of the visible bones are part of a tail in life position. Bottom: Fossilized skin impression found in association with this skeleton. This particular specimen is the “Dangling Dino” described in the chapter. schedule, and the flight crew was briefed about the day’s operation. An old flatbed truck would be waiting back at the nearest road so that the pilot could lower the fragile cargo directly into the vehicle. The weather was gorgeous, clear and crisp—typical for a fall morning in southern Utah. Whereas it took us a good hour to hike out to the site from the road, the two-person crew flew the A-Star B2 helicopter out there in a few short minutes. Hovering above the hilltop, the ground crew attached the cable to the heaviest block, which contained most of the pelvis, hind limb, and tail of the duck-billed dinosaur. The pilot attempted to raise the oddly contoured, ivory white package several times before concluding that it was too heavy. Upon hearing this news, my mind reeled at the thought of accessing (and paying for) a larger helicopter. I then recalled hearing of a similar airlift in Alberta that had gone 236 • WEST SIDE STORY Sampson_ch14.qxd 7/9/09 1:25 PM Page 237 much worse; the pilot had managed to get the dinosaur skeleton airborne only to find that he could no longer control the helicopter in the wind. Making a split-second decision, he elected to detach the cable. The jettisoned dinosaur experienced a brief freefall before col- liding abruptly with the earth, transforming the precious cargo into dust. No, for the sake of humans and fossils alike, discretion is clearly the better part of valor in such endeavors. Unable to handle the largest load, the crews began the process of airlifting the remain- ing skeletal blocks, all of which were considerably smaller. At the culmination of each trip, the pilot deftly maneuvered the cargo into the awaiting truck, where additional crew members were on hand to detach the lift cable. After the last of the smaller packages was secured, the pilot announced that he was going to give the largest block one last attempt.

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