Rapid shoreline regression and transgression along the western Gulf of Maine between 13,000 and 9,000 years BP are inferred to have produced a nearshore marine environment low in biologic productivity. Palaeo-Indians living near the coast of the Gulf were probably forced to rely on nonmarine resources landward of the late-glacial marine limit. Thus, Palaeo-Indian sites of the time period in question may be restricted in the region between the marine limit and the postglacial low sea level stand, or may be altogether absent.