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The sixth PELD ILOC (Long-Term Monitoring of the Brazilian Oceanic Islands) expedition to Fernando de Noronha  Archipelago took place between October 20th and 31st, 2018 and was attended by the researchers Carlos Eduardo Leite Ferreira (UFF/LECAR), Sergio Floeter (UFSC/LBMM), Julia Biscaia Zamoner (UFSC/LABAR), Mariana Teschima (UFRJ), Ronaldo Bastos Francini-Filho (UFPB), Guilherme Ortigara Longo (UFRN/LECOM) and Thayná Mello (ICMBio-Fernando de Noronha). During the 12 days at the archipelago, which is located 200 miles from Brazilian northeast coast, the researchers carried out activities related to the annual monitoring of reef fish assemblage (visual censuses), benthic community structure(photo-quadrats), health status of Siderastrea and Montastraea colonies (photo-quadrats and, for Siderastrea, filming for 3D modelling) and population structure of Grapsus grapsus, besides the setup of seawater temperature sensors. Activities of other researchers associated to the project were also developed, such as the collection of corals for studies of zooxanthellae – microalgae that inhabit the colonies, providing them food and being responsible for their different colours -, as well as the placing of information signs for the De Olho Nos Corais project. The good weather and sea conditions, the excellent teamwork and support of ICMBio and diver operators resulted in a successful expedition, full of hard work, discussions and learning! Natural beauties, both into and out of the water, as always, made the expedition even more incredible! We’re just ready for the next one!

The expedition to ASPSP that occurred between September 16 and 30, the team was composed by Larissa (UFAL), Thayna (ICMBio), Caio (UFES) and Moysés (UFF). The arrival happened on the night of 16/9 after 100 hours of sea. Some problems due to weather conditions prevented the actions of the PELD in the last two days, however, the expedition was completed positive balance and a relevant number of samples collected and monitoring images. A total of 80 dives were performed to improve the sampling. The ASPSP monitoring included 40 visual fish censuses, 33 plots videos of three different depths, 9 fixed benthic transects, G. grapsus census, algae collections, dinoflagellates and 20 BRUVs. The fixed transects were changed and the thermometers of the different depths were also changed. This expedition was supported by Guilherme Longo and Zélia Brito.

During May and June, three researchers of PELD-ILOC conducted extensive data collection on Rocas Atoll, one of the Brazilian oceanic islands monitored by the initiative. The team was formed by Dr. Vinicius Giglio (UFF), Dr. Katia Capel (URFJ), M.Sc. candidate Vitor Picolloto (UFSC), and the reserve assistance was provided by Jarian Dantas (ICMBio). The main objective of this expedition was to perform the annual monitoring of reef components, and the activities included underwater visual censuses to assess reef fish assemblages, photoquadrats for the benthic community and sampling of the crab Grapsus grapsus.
Researchers observed relatively high abundances of reef fish, mainly mesopredators such as the dog snapper Lutjanus jocu, lemon shark Negaprion brevirostris and the nurse shark Gynglimostoma cyrratum. These are clear indications of the effectiveness of the marine protected area.

In a place of intense endemism and low diversity of species, the Aratu Crab (Grapsus grapsus) plays a key role in the reef environment, strongly acting as a connection between the intertidal and subtidal reef environment. Considering that in the western South Atlantic G. grapsus occurs only in the Brazilian oceanic islands and that the ASPSP population is maintained by self-recruitment, without considerable dispersion of the species, long-term monitoring of the Aratu Crab populations is justified, not only because of its direct influence on the reef pelagic system, but also because it signals the environmental conditions of adjacent rocky shores. When assessing the results of the ASPSP monitoring over the last few years, performed by counting G. grapsus at 10 transects and by subsequent analysis of the structure of 100 individuals, there is a tendency of a decreasing abundance of crabs, a decreasing size of ovigerous females and an increasing proportion of mutilated organisms over time. Therefore, there is a need for a longer period of monitoring, since if the trend of these parameters is confirmed, a change in the environmental factors of the archipelago and a decrease in the fecundity rate and supply of larvae to the reef environment are revealed. The whole article is available in the book chapter “Temporal Variation of the Preserved Communities in the São Pedro and São Paulo Archipelago: Actions of the Long-Term Monitoring Project (PELD/ILOC).

The archipelago of St. Peter and St. Paul’s is a set of Brazilian oceanic islands farther from the coast. It is a place well preserved and, thus, of particular importance for marine biodiversity. In St. Peter and St. Paul’s Archipelago the PELD-ILOC aims to carry out monitoring of this biodiversity, especially of the ichtyofauna, providing important information which show more and more the specialty of this place. St. Peter and St. Paul’s Archipelago has the lowest diversity of fishes in the South Atlantic, but, however, a high rate of endemism. We find species with different morphologies and different color patterns that do not occur in other islands of the Atlantic. Until a depth of 50 m, the St. Peter and St. Paul’s Archipelago reefs are well known compared to other Atlantic Islands. Recent expeditions have investigated the mesophotous fish, that occurs between 30 and 90 meters depth, a hitherto little described habitat. Since 2013, the monitoring of the ichthyofauna has been performed annually. It was observed that about 90% of the fish analyzed in the first year, were again observed in the following years. In these years, there were events of fish biomass and density being related to the large number of species. The species size has increased little during the years with carnivorous species increasing especially in the first years decreasing to their average size within the last two years. Furthermore, there was no shark species recorded during any expeditions. This article is available in the book chapter “Temporal Variation of the Preserved Communities in the St. Peter and St. Paul’s Archipelago: Actions of the Long-Term Monitoring Project (PELD-ILOC), see also “Publications”.