Immediate effects of the 2019 oil spill on the macrobenthic fauna associated with macroalgae on the tropical coast of Brazil

The 2019–2020 Brazil oil spill disaster affected several ecosystems and species-rich areas. The shallow-water reefs of Paiva beach are among the best-preserved coastal environments in the State of Pernambuco (NE Brazil), but were severely affected by oil arrival at the end of 2019. The reefs are densely covered by macroalgae as important biogenic substrates for benthic fauna. Based on that, herein, we provide a baseline assessment of the immediate impacts of the oil spill on the structure of epifaunal communities associated with the algae Jania capillacea and Penicillus capitatus. The benthic communities in both algae simplified (reduction of species richness and abundance) soon after oil arrival, while opportunistic taxa increased. After two months, the macrofaunal communities restructured to almost pre-disaster levels. However, polychaeta diversity remained low. Despite the apparently fast recovery of reef macrobenthos, a more detailed, long-term monitoring is necessary to evaluate the chronic effects. •In the week of the disaster several algae and organisms had oil adhered to them.•After the oil arrival increased the number of B. luctuosum and J. gracilis.•The changes in epifauna at the community level were relatively small in our study.•First study of the 2019 Brazilian oil spill in the benthic fauna associated with macroalgae