Fishing up the Food Web?: 12,000 Years of Maritime Subsistence and Adaptive Adjustments on California’s Channel Islands

Archaeologists working on California’s northern Channel Islands have produced an essentially continuous record of Native American fishing and nearshore ecological changes spanning the last 12,000 years. To search for evidence of Pauly’s ‘‘fishing down the foodweb’’ pattern typical of recent historical fisheries, we analyzed variation in the dietary importance of major marine faunal classes (shellfish, fish, marine mammals) on the islands through time. Faunal data suggest that the Island Chumash and their predecessors focused primarily on low-trophic-level shellfish during the Early and Middle Holocene, before shifting their economic focus to finfish and pinnipeds during the Late Holocene. Replicated in faunal sequences from the adjacent mainland, this trans-Holocene pattern suggests that Native Americans fished up the food web, a strategy that may have been more sustainable and had fewer ecological repercussions. Emerging technological data suggest, however, that some of the earliest Channel Islanders focused more heavily on higher-trophic-level animals, including marine mammals, seabirds, and waterfowl. These data emphasize the differences between the primarily subsistence-based foraging strategies of ancient Channel Islanders and the globalized market-based fisheries of modern and historic times, with important implications for understanding the longterm evolution and historical ecology of marine ecosystems. Until quite recently most scholars believed that humans developed boats, maritime technologies, and intensive fishing economies during only the last 10,000 years or less (see Bailey 2004, Erlandson 2001). Consequently, there was little reason to think that humans colonized most islands or had serious impacts on coastal fisheries and ecosystems until quite late in the Holocene (Erlandson and Rick 2008). This idea may be true for the more remote Pacific islands of Micronesia, Melanesia, and Polynesia, first settled by maritime agriculturalists during the Late Holocene, but it may not apply for many of the lessremote islands of the Pacific Rim, especially Island Southeast Asia, Australia and New Guinea, western Melanesia, and the Ryukyu Islands, which were all colonized by seafaring peoples between @50,000 and 35,000 years ago (Erlandson 2002). The idea that maritime peoples may have contributed to the initial colonization of the Americas has also gained credibility in recent years, as increasingly early sites have been found along the Pacific Coast of the Americas (e.g., Sandweiss et al. 1998, Johnson et al. 2002, Fedje et al. 2004, Des Lauriers 2006, Dillehay et al. 2008, Erlandson et al. 2008a), despite dramatic changes in coastal landscapes Pacific Science (2009), vol. 63, no. 4:711–724 : 2009 by University of Hawai‘i Press All rights reserved 1 Research has been supported by grants and other assistance from the National Science Foundation, National Park Service, University of Oregon, Southern Methodist University, National Marine Fisheries Service, U.S. Navy, Western Parks Association, the Foundation for Exploration and Research on Cultural Origins, and the Marine Biology Conservation Institute. Manuscript accepted 30 January 2009. 2 Museum of Natural and Cultural History and Department of Anthropology, University of Oregon, Eugene, Oregon 97403-1224. 3 Archaeobiology Program, Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington D.C. 20013-7012. 4 Department of Anthropology, Humboldt State University, Arcata, California 95521. 5 Corresponding author (e-mail: jerland@uoregon.