Successjil Mormon colonization of the American West has largely been attributed to the adaptive advantage of cooperative Mormon values. This article shows that successjid Mormon colonization of the Little Colorado River Basin had an ultimate ecological basis: the redistribution of surplus resources among settlements situated in dispersed and4nctionally independent local environments. Two systems of resource redistribution among 19th-century Little Colorado Mormon settlements are examined, showing that ecological considerations explain their diflerential success as adaptive mechanism contributing to the success of this local colonization eflort. The article concludes by suggesting that general ecologY provides a use& theorcticaljamework for explaining successjid Mormon colonization in this region and elsewhere.