Small-scale fisheries are vital for millions of people worldwide, but hard to monitor and manage. We investigated the effects of variables related to different spatial scales and theoretical backgrounds, from protected areas (PA) to individual decision-making, on parameters of small-scale fisheries (catch, effort, and catch per unit of effort - CPUE) in the Tapajós and Negro rivers, Amazon. Although both individual- and large-scale variables affected fish landings, the former group was more important. Fish sales, group fishing, and the fishing technique used were the most important variables affecting all parameters. Number of activities performed and time traveled to fishing spot influenced effort and catch. Education level was negatively related with effort. At the large-scale, fishing effort and catch were higher outside PA. Distance to the urban center was positively related with CPUE. Large-scale predictors of fishing yields could help to define broader management goals, while variables at the individual-level may help to identify vulnerable groups to changes in fisheries and to adjust management to minimize conflicts, improving acceptance and compliance.