Patterns of Population Movement and Long-Term Population Growth in Southwestern Colorado
In spite of considerable fluctuations in the likelihood of agricultural success from place to place and from time to time, the southern Colorado Plateaus show a smooth increase in farming populations between A.D. 1 and 1150. At the local level, however, population curves in this region often register a pattern of short-lived occupations and abandonments that are tied to specific patterns of short-term and long-term climatic conditions. The prehistoric population record from the Dolores area, in the southwestern corner of Colorado, demonstrates how localized population adjustments to climatically sensitive environments can result in long-term population increases. Here, a 600-year history of population increase was maintained primarily through population movements between environmentally complementary places. When that strategy failed, due to a combination of adverse short-term and long-term climatic conditions, agricultural methods shifted from rainfall farming to intensified agriculture supported by water-control facilities.