Bridging archaeology and marine conservation in the Neotropics

Abstract Anthropogenic impacts on tropical and subtropical coastal environments are increasing at an alarming rate compromising ecosystem function, structure and services. Understanding the scale of marine population decline and diversity loss requires a long-term perspective that incorporates information from a range of sources. The Southern Atlantic Ocean, however, represents a major gap in our understanding of pre-industrial marine species composition. Here we contribute to fill this gap by performing an extensive review of the published data on Middle and Late Holocene marine fish composition along the southern coast of Brazil. This region preserves archaeological sites that are unique archives of past socio-ecological systems and of pre-European biological diversity. We assessed snapshots of species compositions and relative abundances spanning the last 5000 years, and modelled differences in species’ functional traits between archaeological and modern fisheries. We found evidence for both generalist and specialist fishing practices in pre-European times, with large body size and body mass caught regularly over hundreds of years. Comparison with modern catches revealed a significant decline in these functional traits, possibly associated with overfishing and the escalating human impacts in recent times.