This study is a historical account of the productive strategies of peasant families in the middle Solimões River. It attempts to establish a framework of the changes that occurred in the perception of producers in relation to the value of production, thus reflecting on a “riverside economic rationality”, which shows possible changes in the patterns of development and commitment of households to economic activities, resulting from changes in agriculture and fishing. For this purpose, we discuss different production strategies in five communities in the region of Fonte Boa, in the state of Amazonas, located in a lowland area and within the territorial limits of the Mamirauá Sustainable Development Reserve (RDSM). Data were collected in 2013, from 23 households in the communities of Araçari, Terra Nova, Monte Cristo, Batalha de Baixo and Bela Vista do Batalha. The data show that the motivation in choosing one activity over others is not the price of production in the market, but also the effort used by the group to guarantee the production and availability of labor and natural resources. This further indicates that economic strategies are directly linked to the need to guarantee the livelihood of the domestic group.