ABSTRACT The 1994 discovery and excavation, on Santa Rosa Island, of the most complete pygmy mammoth (Mammuthus exilis) skeleton yet recovered prompted additional research of the California Channel Islands. An intensive, pedestrian survey of mammoth localities tied to GPS coordinates was initiated for the first time in the history of the island mammoth research and has resulted in the discovery and documentation of more than 100 new localities. Several mainland-size mammoth (Mammuthus columbi) elements were recovered. These may represent: 1) ancestral animals; 2) contemporary animals; or 3) late migrant animals. Dental and osteological metric analyses in progress will allow comparisons and contrasts to mainland M. columbi populations. Six new radiocarbon dates from San Miguel and Santa Rosa islands have been added to the eleven published dates for mammoth and mammothassociated material. These new dates include an AMS bone collagen date of 12,840 ± 410 yr B.P. (CAMS 24429) derived from the right femur of the 1994 skeleton.