BISON CF. B. ANTIQUUS FROM THE LATE PLEISTOCENE AIRPORT LANE FOSSIL SITE, LA GRANDE, NE OREGON

Bison fossils found at the Airport Lane site in January 2010 include seven articulated bison vertebrae (T-13 to L-5); a left radius/ulna; a whole left ulnar carpal; fragments of the left radial carpal, left intermediate carpal, second/third carpal, and the accessory carpal; and the proximal part of a left calcaneus. The proximal (dorsal) surfaces of the first, second, and third carpals match the distal end of the left radius. This suggests that the radius and carpals are from the same animal. Fragments of the bison vertebrae yielded an AMS radiocarbon date of 12,950 ± 50 ¹⁴C years BP. The greatest length (386 mm) and greatest breadth of the proximal end (129 mm) of the Airport Lane bison radius are similar to the measurements of the smallest male B. latifrons radii from the ~32-21 Ka American Falls Reservoir site in Idaho described by Stevens (1978). The greatest breadth (114 mm) and the greatest depth (66 mm) of the proximal articular surface of the Airport Lane radius are close to those of the largest male B. antiquus from the Lipscomb site in Texas. It is possible that the bison from the Airport Lane fossil site is B. latifrons, but, based on the dimensions of the radius, the age, and the observation that only B. antiquus fossils have been found in nearby areas, it is more likely that it is a very large male B. antiquus. The Airport Lane bison may be a long-legged form of B. antiquus similar to the insular form found on Orcas Island, Washington, described by Kenady and others (2011). The bison bones discovered at the Airport Lane fossil site are the ones most commonly left behind at butchering sites such as the Hudson-Meng bison kill site in Nebraska described by Agenbroad (1978), but no butchering marks or tools have been found at the Airport Lane fossil site.