GLASGOW, Mont. -- The skull of what is believed to be the largest Tyrannosaur on record has been seriously damaged by poachers on the northeastern Montana cattle ranch where the fossilized dinosaur skeleton was found, according to University of Notre Dame paleontologist J. Keith Rigby.
The damage was discovered today when Rigby and his field crew, including Notre Dame students, returned to the site and found that two-thirds of the left side of the skull was missing. Both of the lower jaws also were missing.
The FBI in Great Falls took possession last Friday of two fossilized jaws that are believed to belong to the Tyrannosaur discovered by Rigby. The bones were turned over to the FBI by two unidentified people, according to news media reports. The federal Antiquity Act protects fossils on federal land. No arrests have been announced.
"This is about as bad as I could have imagined," Rigby said today. "We had a virtually complete skull and now I'm wondering what I can do to repair the damage."
Rigby and a crew of volunteers from the Earthwatch Institute discovered the skeleton this summer in a vast dinosaur graveyard near the Fort Peck Reservoir.
The fossil, which was nearly complete, is either a Tyrannosaurus rex or something very much like it. Certain aspects of the anatomy are different than the 15 or so known skeletons of T. rex, according to Rigby, and it appears to exceed all measured skeletons of the dinosaur. "What we do know," he said, "is that this is the largest carnivore on the planet."
Unable to complete the excavation this summer, Rigby and his assistants covered the site for the winter. However, former owners of the cattle ranch on which the fossils were found entered the site two weeks ago and began digging up the bones that remained in the ground. The ranchers contend they still own the land, although a title search indicates it now belongs to the U.S. Department of Agriculture's Farm Service Agency.
Federal law enforcement officers descended on the site Sept. 14 and forced the former owners to vacate the premises.
Situated in the picturesque badlands of eastern Montana, the site lies in the Hell Creek, a geological formation famous for preserving dinosaur bones. The bones date from the end of the Cretaceous period 66 million years ago. In the Late Cretaceous, the now bond-dry site appears to have been a river channel. When the dinosaurs died, their bones washed into the channel and collected together there. Sediments covered and preserved the bones until they were discovered in July
Judging from the position of both surface bones and the bones so far unearth, Rigby believes the bone bed might cover 15 acres, making it one of the largest dinosaur graveyards of the Late Cretaceous ever found.