The Lake Titicaca Basin is one of the regions in the world where both primary village and state formation occurred in prehistory. Although agriculture has been discussed as the central engine fueling these processes, fish and other aquatic resources were significant but little-understood components of the region's ancient economy. In this paper, we use zooarchaeological analysis of faunal remains from 367 flotation samples recovered from five archaeological sites to discuss the interplay between fishing, environmental change, and the emergence of sociopolitical complexity in the Taraco Peninsula of Lake Titicaca. Our results suggest that fishing comprised a significant component of the local inhabitants' diet between 1500 BC and 1100 AD. The intensity of fish procurement, however, varied through time and independently of both climatic and population change. We interpret variation in fish consumption through time as a product of group and individual decisions to optimize resource use in a context of dynamic environmental and sociopolitical variability. © 2014 Elsevier Inc.