The bird life of the central Peruvian Amazon is poorly known. To better characterize bird diversity and distributions, we conducted 4 expeditions to this lowland area, totaling 114 field days in 2015, 2018, and 2019. We focused on sampling under-surveyed habitats, terra firme in multiple interfluves, and sites around a recent river avulsion, and we detected 657 bird species across 22 study sites. Our results include the first extensive inventories of blackwater wetland systems, Guadua bamboo tracts, and riverine islands in central Peru; revised information on distributions with respect to river barriers, including documentation of contact and putative hybridization between parapatric forms; 28 first regional records; and new details on poorly known taxa. Together, these results provide a more complete picture of avian diversity in an area characterized by high species richness, high habitat diversity, and biogeographic interchange.