STRATIGRAPHY AND EXTINCT LATE PLEISTOCENE MEGAFAUNA FROM DOVE SPRING WASH, NORTHWESTERN MOJAVE DESERT, KERN COUNTY, CALIFORNIA

A sequence of unnamed Quaternary stream and pond deposits in Dove Spring Wash, Red Rock Canyon State Park, Kern County, California, has previously yielded diverse microfauna containing molluscs and small vertebrates. Fieldwork in early summer of 1990 yielded fossil remains of extinct large vertebrates from a complex series of Quaternary stream and pond sediments that predate previously-described lignitic sandstones by several thousand years. Taxa represented from these older sediments include possible canid (cf. Canis sp.), Columbian mammoth (Mammuthus columbi), large horse (Equus sp. cf. E. “occidentalis”), large camel (Camelops hesternus), and bison (Bison antiquus). The bison is represented by a partial skeleton. Mammoth tooth fragments from the deposits yielded a radiocarbon date of 19,190 ±410 ybp; a rib from the bison skeleton yielded a date of 16,860 ±1175 ybp. The occurrence of M. columbi, large Equus, and C. hesternus in the fauna corresponds with the composition of other late Pleistocene faunas in the Mojave Desert. The presence of B. antiquus is unusual, as this species is very rare from the Mojave and may be a relatively late immigrant. The presence of these large herbivores in the northwestern Mojave Desert suggests the presence of abundant fresh water and forage in the region during and following the peak of the Wisconsin glaciation, although low specimen abundance and the lack of temporally associated microfaunal remains prevent more precise paleoenvironmental reconstructions.