Fig. 1.

Mean bone collagen isotope values of ancient pinnipeds as well as abundance estimates from selected archaeological sites. Pie diagrams show the relative abundance of NFS remains (shaded) versus other pinniped remains based on the number of identifiable specimens. Mean δ¹³C/δ¹⁵N values (SD) for adult female NFS and HS are reported beneath each labeled group of NFS or HS; the asterisk denotes previously published HS data from the southern region (19). A site-by-site compilation of pinniped isotope values is available as SI Table 1. NFS cluster into northeastern Pacific (squares), California (circles), and western Aleutian populations based on significant differences in isotopic values. Filled symbols denote sites with harvest profile data (see Fig. 2). Locations of islands mentioned in text are shown: ✷, Pribilof Islands, eastern Bering Sea; ▵, Bogoslof Island, eastern Aleutians; X, Farallon Islands off San Francisco Bay; ⊕, SMI off southern California.