Francini-Filho et al. 2019

scientific chapter |


Francini-Filho RB, Márquez Velásquez V, da Silva MB, Rosa MR, Sumida PYG, Pinheiro HT, Rocha LA, Ferreira CEL, Francini CLB, Rosa RdS


Indirect evidence for the occurrence of mesophotic coral ecosystems (MCEs) in Brazil dates back to the 1960s. Only in the last 10 years have Brazilian MCEs been studied systematically, through the use of new tools such as trimix technical diving (open and closed circuit), remotely operated vehicles (ROVs), drop cameras, submersibles, and sidescan sonar. Brazilian MCEs occur along an extensive latitudinal gradient, from the Amazon Reef in the north (5° N) to the Vitória-Trindade Seamount Chain in the south (21° S). Fisheries data and in situ unpublished observations indicate that MCEs also occur further south (24° S), where scleractinian corals, octocorals, and reef fishes are commonly found over rock bottoms between 30 and 70 m. The primary research topics published in the last decade include habitat mapping, benthic and fish assemblage structure, biodiversity surveys, microbial abundance and function, ecosystem assessment, evolution, and conservation. A conservative estimate indicates that at least 25 species of elasmobranchs, 275 teleost fishes, and 476 sessile benthic species (234 algae, 166 sponges, and 76 anthozoan cnidarians) occur in Brazilian MCEs. The primary reef builders are coralline algae (both encrusting and free-living nodules) and the scleractinian coral Montastraea cavernosa. Benthic assemblages are generally dominated by sponges, black corals, and octocorals. Fish assemblages are dominated by planktivorous fishes, while piscivorous species, particularly jacks (Carangidae), are also abundant at mesophotic depths. Overfishing, mining, and pollution are among the main threats to Brazilian MCEs.