Late Pleistocene to Holocene history of Lake Warner and its prehistoric occupations, Warner Valley, Oregon (USA)

During the late Pleistocene, Warner Valley (Oregon, USA) was filled by Lake Warner; however, little is known about its rise and fall and how its changing lake levels effected the distribution of the valley’s earliest occupants. The discovery of Paleoindian projectile points along ancient shorelines of the lake spurred us to examine them for geochronological controls to aid in constructing the lake’s history. We found that Lake Warner filled the valley floor between ca. 30,000 and 10,300 cal yr BP, probably reaching its maximum ca. 17,000–16,100 cal yr BP before it began to recede. People arrived with Clovis and Western Stemmed Tradition (WST) projectile points before ca. 12,800 cal yr BP, around the time the lake stalled in its retreat. When the lake continued its decline, people using WST points followed it southward into the valley floor, where dune-and-slough topography began developing ca. 10,300 cal yr BP in response to episodic wetting and drying during the early Holocene. By the time Mazama tephra fell, ca. 7600 cal yr BP, the once large lake was divided into a series of small lakes, ponds, and sloughs that attracted people to their abundant resources of endemic fish and marsh plants.

Diachronic variability in prehistoric land use in Oregon’s Warner Valley

Pedestrian survey in northern Warner Valley, Oregon, has provided data capable of contributing to reconstructions of prehistoric land use. Such information is complementary to data generated by recent work at the stratified LSP-1 rockshelter situated in the Northern Warner Valley Study Area (NWVSA). Here, we present results of our survey and focus on when the area was visited, how it was used, and from where visitors to the area originated and/or obtained toolstone. Our results indicate that the NWVSA saw heavy use by Paleoindians before being largely abandoned during the Middle Holocene. During the Late Holocene, groups likely operating from residential bases further south in the better-watered parts of Warner Valley returned to the NWVSA. Compared to other nearby areas, the NWVSA was utilized less intensively during much of the Holocene.