Productive areas are typically associated with specific types of structure. Deep pools located at bends in the river are prime holding areas for large catfish. Confluences where smaller streams or igarapés meet the main river channel attract baitfish and predators. Areas with extensive submerged timber and fallen trees (galhadas) are excellent ambush points for peacock bass. Backwater lagoons and oxbow lakes connected to the river during high water hold concentrated fish populations during the low-water period.