Materials and Methods
We re-censused the avian community in a 97-ha mature forest floodplain plot located at Cocha Cashu Biological Station, in Manu National Park in southeastern Peru, following the methodology of the original 1982 census (Terborgh et al. 1990). Given the hyper-diverse bird community at this location, these censuses required a variety of sampling methods to estimate species abundances and biomass on the plot. Estimating abundances for an entire hyper-diverse bird community requires a massive effort that logistically precludes regular periodic censuses. Over the course of the 2018 and 2019 field seasons, 16 different individuals (including two of the original census authors) contributed to data collection using the census approaches outlined below. In addition, several individuals re-digitized the original territory maps of each species (requiring ~320 hours). We replicated all of the original census methods to derive comparable estimates of abundance for the majority of species found on the plot. In what follows we describe each of these methods in detail. Scientific names of birds follow the latest taxonomy from the South American Classification Committee.