Quebrada Tacaacaacahuay represents one of the oldest expressions of maritime adaptations in the Americas, with initial deposits dating to the Late Pleistocene and minor reoccupation of the site during the Early and Middle Holocene (deFrance 2002; deFrance and Umire 2004; deFrance et al. 1998, 1999, 2001; Keefer et al. 1998, 2003). Representing an ancient specialized activity site dating to more than 10,500 (rcyr BP) and focused on the exploitation of marine avifauna, the oldest contexts of human use at Quebrada Tacahuay are also intriguing because of the nature of their preservation, discovery, and archaeological investigations. Although many areas of the Andean littoral may have been occupied during the Late Pleistocene, only those relatively few sites located on land surfaces where the coastal shelf is very narrow survived rising sea level at the end of the Ice Age (Richardson 1998). In addition, preservation of the oldest anthropogenic deposits at Quebrada Tacahuay is the result of burial by a massive debris flow that was triggered by an ENSO paleoclimatic event (deFrance and Keefer 2005; Keefer et al. 1998, 2003). Subsequent flood events, as well as natural accumulations of aeolian sands, further sealed the deposits.