Bonfire Shelter, the oldest mass bison-kill site in the New World, lies in a deeply entrenched canyon one kilometer above its juncture with the Rio Grande near Langtry, Texas. This large rockshelter, hidden behind a massive roof fall, holds three bone deposits and at least two occupational levels, each stratum separated from the others by sterile cave fill. The lowest bone deposit contains the scattered skeletal remains of now-extinct large game animals, such as elephant, camel, horse, and bison. These species ranged the lower Pecos region at the end of the Pleistocene, about 14,000 to 12,000 years ago. The intermingling of the bones of so many species, the cut marks and breakage patterns on the bones, and the presence of large, anvil-like limestone blocks indicate that this site was used as a butchering station. The second, younger bone bed contains only bison bones of the now extinct species Bison antiquus. About 120 animals are represented by body parts. Stone tools, including Paleo-Indian arrowheads such as Folsom and Plainview, and radiocarbon assays of charcoal from small hearths date this level to 10,000 years ago, when herds of the giant bison were driven over the cliff above, killed on the rocks below, and either rolled or dragged into the shelter for butchering. Over 7,000 years later the site was again used for the same purpose, the stampeding of herds of modern bison to their death (see BUFFALO). The discarded bones, meat, and fat, the residue from butchering, apparently ignited spontaneously and reduced this bone deposit to ash and burned and brittle bone.
In the third level, among the remains of an estimated 800 bison, numerous stone tools were found, including projectile points similar to the Montell and Castroville types more common in Central Texas. Pollen (see PALYNOLOGY) and other environmental indicators support the theory that during a short mesic interlude about 2,600 years ago the grasslands of the Southern Plains extended into the lower Pecos, bringing the bison herds and their attendant hunters into the region until a return to arid conditions forced their retreat. Bonfire Shelter is thus both the oldest and the southernmost example of the jump technique of bison hunting and the only site of this type yet recorded on these margins of the Southern Plains. Its preservation can be attributed to the massive roof fall, which diverted the falling bison into the shelter rather than into the canyon, where their remains would have been washed away by flood.
Bonfire Shelter was excavated in 1963–64 and 1983–84 by the Texas Archeological Survey. Faunal remains are curated at the Vertebrate Paleontological Laboratory, and artifacts, notes, and photographs are stored at the Texas Archeological Research Laboratory and the Texas Memorial Museum at the University of Texas at Austin.