Local, regional, and global extinctions caused by habitat loss, degradation, and fragmentation have been widely reported for the tropics. The patterns and drivers of this loss of species are now increasingly well known in Amazonia, but there remains a significant gap in understanding of long-term trends in species persistence and extinction in anthropogenic landscapes. Such a historical perspective is critical for understanding the status and trends of extant biodiversity as well as for identifying priorities to halt further losses. Using extensive historical data sets of specimen records and results of contemporary surveys, we searched for evidence of local extinctions of a terra firma rainforest avifauna over 200 years in a 2500 km(2) eastern Amazonian region around the Brazilian city of Belém. This region has the longest history of ornithological fieldwork in the entire Amazon basin and lies in the highly threatened Belém Centre of Endemism. We also compared our historically inferred extinction events with extensive data on species occurrences in a sample of catchments in a nearby municipality (Paragominas) that encompass a gradient of past forest loss. We found evidence for the possible extinction of 47 species (14% of the regional species pool) that were unreported from 1980 to 2013 (80% last recorded between 1900 and 1980). Seventeen species appear on the International Union for Conservation of Nature Red List, and many of these are large-bodied. The species lost from the region immediately around Belém are similar to those which are currently restricted to well-forested catchments in Paragominas. Although we anticipate the future rediscovery or recolonization of some species inferred to be extinct by our calculations, we also expect that there are likely to be additional local extinctions, not reported here, given the ongoing loss and degradation of remaining areas of native vegetation across eastern Amazonia.

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We carried out seven two-week long avifaunal inventories in five newly-established conservation units spanning the entire ‘Calha Norte’ area, a portion of the Guiana Shield in the northern part of the state of Pará, Brazil, between January 2008 and January 2009. Prior to our study, most of this part of Amazonia was regarded as virtually unsampled from an ornithological perspective. Here, we present an annotated check-list with 446 species of birds recorded during the surveys, including 62 species for which our records represented significant range extensions, and hence are discussed in detail. The number of species recorded at each site varied between 203 and 302, and was positively correlated with the local availability of steep altitudinal and vegetational (forest/savanna and seasonally-flooded/upland forest) gradients. The number of unique species recorded at each site varied between 2 and 27, and reflected an interesting biogeographic pattern in which the Trombetas river appears to separate distinct upland and white-sand forest bird faunas on the Guiana Shield, a pattern also verified for the herpetofauna. Our results also showed that savannas represent a very important component of the local biota, with enclaves harboring a typical bird fauna also distributed in similar habitats in nearby southern Guyana, Suriname, and the state of Amapá in Brazil. Altogether, the five conservation units surveyed harbour 74 bird species of special interest for conservation (threatened, endemic, rare, range-restricted, and hunted species) and therefore play a key role in the preservation of all main subsets of the heterogeneous bird fauna of the Guiana Shield.