Revisiting 150 years of coral studies to assess changes in species records, distribution, and functional structure of corals in the Brazilian Province

Abstract

Historical information serves as a crucial foundation for understanding past natural ecosystems, enabling us to track changes in biodiversity. It plays an indispensable role in both biodiversity conservation and restoration ecology. In the Brazilian Province, there is still an absence of historical accounts relative to the coral assemblage diversity. We compiled historical and modern information on coral species and mapped coral diversity in the Brazilian Province over the past 150 years. Using abundance data, we contrasted the functional structure of coral assemblages sampled 40 years apart (1960–2000) in the Abrolhos Bank, the largest reef complex of the Southwestern Atlantic Ocean. The number of species records increased over time, especially after the 1960's, with the Abrolhos region amassing numerous historical accounts and harboring the greatest coral richness. This increase in species records reflects the recent accumulation of knowledge about these marginal reefs. Historical declines of two major reef building species, Millepora alcicornis and Mussismilia braziliensis, resulted in temporal changes in their relative contributions to the functional structure of coral assemblages in the Abrolhos Bank. The erosion of such assemblages within the past 40 years highlights the importance of considering historical information to adjust environmental baselines, setting proper conservation and restoration targets.