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The life history of marine invertebrates is intrinsically related to the environmental conditions of their habitats. However, the effect of environmental factors on life history traits, e.g. reproduction, is poorly understood due to difficulties in cultivating these animals in controlled conditions. Natural experiments, using latitudinal gradients, provide an alternative to better understand this relationship. We investigated the effect of environmental factors on some aspects of the reproduction of Tedania ignis (Porifera, Demospongiae) along a latitudinal gradient in the Western Atlantic Ocean (WAO). We assessed the predicted trade-off between size and fecundity and biogeographical patterns in some of the life history traits of this sponge species. Except for the southernmost population, all populations of T. ignis reproduced aperiodically, but their reproductive dynamics were modulated by different sets of environmental factors. Therefore, this trait seems to be a physiological adaptation to local conditions. Nonetheless, the species reproduced mainly when the temperature was above 21°C, which could be a factor limiting its distribution along the tropical WAO. We did not detect any trade-off between size and quantity of oocytes and larvae in this species. A possible explanation is that the species invests low energy in offspring in a given period, resulting in a low but continuous reproductive effort, independently of the environmental conditions. These findings will be important to support management plans, as this species is a potential target for obtaining biotechnological natural products.

The detection and control of invasive alien species in marine ecosystems is especially challenging because it is difficult to visualize the full extension of an invasion, while control options are often limited. The invasive scleractinian coral Tubastraea coccinea have spread over 8000 km of the Atlantic coastline, from Florida in the USA to southern Brazil, mainly in association with oil and gas platforms. This invasive coral threatens endemic species, reduces native coral recruitment, and modifies communities and trophic interactions, posing a relevant threat to shallow Atlantic reefs. The main aim of our study was to assess the effectiveness of an ongoing T. coccinea control program by analyzing the results of control interventions on population structure and cover of the target species in its southern Atlantic limit of distribution. We also describe the reproductive effort of T. coccinea in a 12-month time span. Between 2012 and 2019, almost 14,000 colonies were removed, most of them of small size (

Preventing, detecting, and monitoring invasive marine species is a big challenge as it is not possible to visualize all invasion extensions. Their early detection may be the best chance to achieve eradication. The Indo-pacific scleractinian coral Tubastraea coccinea invasion in the Atlantic dates from the late 1930s. Since then, disruptive populations were found along ~8.000 km of west Atlantic, and in the Canarian Islands of Spain (east Atlantic), related to vessel fouling in the oil and gas industry. Their impacts have been noticed from endemic species to ecosystems. In Brazil, initiatives to control Tubastraea spp. have been done mostly by local environmental managers and researchers, but recently a National Plan for Prevention, Control and Monitoring (NPPCM) for Tubastraea spp. was approved. We applied an Individual-based Model within the invasion history of Tubastraea coccinea in its southern distribution limit in the Atlantic, on the rocky shore of the Arvoredo Biological Marine Reserve. We indicated hotspots for the occurrence of possible emerging invasion sites in the region and expect to support ongoing monitoring programs in defining priority areas for their early detection. The model is easily replicated and might be a valuable tool for decision makers.

Reef benthic communities provide many important ecosystem functions such as nutrient cycling, carbonate accretion and tridimensional complexity. Yet, reefs worldwide face an uncertain future, being threatened by local and global impacts. As an alternative approach to evaluate communities’ changes, functional ecology aims to understand how species shape the environment and how functions conduct ecosystems’ dynamics. The aim of this study was to investigate the temporal dynamics (2013–2019) of the reef benthic community in the most pristine reef in Brazil, Rocas Atoll, using a functional diversity approach. We identified 48 organisms grouped into 17 functional entities (according to their traits’ combination), considering all sampling years. Benthic community was temporally dominated by functional entities responsible for providing low reef tridimensional complexity (represented mainly by turf algae). This dominance reflected in low values of functional entropy, due to uneven abundances distribution between unique functional entities, those that have unique trait combination. Functional richness oscillated over years, but did not show great changes in functional spaces, maintaining an equity in the number of functional entities and indicating stability of reef functions in Rocas Atoll, even with unequal abundances’ distribution. Our study is the first to use a functional approach in temporal scale and represents a baseline for South Atlantic, since it provides the actual state of reef benthic communities using a functional approach, in an environment with no direct anthropic impacts. This can help to predict the effects on some ecosystem functions caused by local and global changes and its consequence for ecosystem services.

Threatened by global warming and extreme climatic events, such as El Niño Southern Oscillation (ENSO) and Marine Heatwaves (MHW), coral reefs worldwide faced the worst bleaching and mortality event between 2014 and 2017, induced by the 2015/2016 ENSO. We evaluated the impacts of ENSO and MHW episodes on bleaching and mortality frequencies of Siderastrea stellata at Rocas Atoll, Southwestern Atlantic, using visual censuses conducted in 2016, 2017 and 2019. Bleaching rate varied significantly along the sampling period (11.71% in 2016, 1.52% in 2017, and 88% in 2019), but mortality was always less than 4%. Bleaching events in Atlantic reefs have been constantly associated with ENSO, until these recent events of the last two years. We suggest that MHW were probably the primary driver of the observed bleaching, especially in 2019, when much higher bleaching rates were observed than in ENSO periods. Although Southwestern Atlantic massive corals are considered more resistant to thermal stress than reefs corals worldwide, the strong events registered since 2019 highlight the need for continuous monitoring to better understand coral bleaching dynamics and improve predictions on the effects of global change in the region. Resumo: Ameaçados pelo aquecimento global e eventos climáticos extremos, como El Niño Oscilação Sul (ENSO) e Ondas de Calor Marinhas (MHW), os recifes de coral em todo o mundo enfrentaram o pior evento de branqueamento e mortalidade entre 2014 e 2017, induzido pelo ENSO 2015/2016. Nesse estudo, avaliamos os impactos dos episódios de ENSO e MHW nas frequências de branqueamento e mortalidade de Siderastrea stellata no Atol de Rocas, Atlântico Sudoeste, a partir de censos visuais realizados em 2016, 2017 e 2019. O branqueamento variou significativamente ao longo do período de amostragem (11,71% em 2016, 1,52% em 2017, e 88% em 2019), mas a mortalidade não, sendo sempre inferior a 4%. Eventos de branqueamento em recifes do Atlântico têm sido constantemente associados ao ENSO, até os eventos recentes dos últimos dois anos. Nós sugerimos que as MHW foram provavelmente o principal impulsionador do branqueamento observado, especialmente em 2019, quando as taxas de branqueamento observadas foram maiores do que nos períodos de ENSO. Embora os corais massivos do Atlântico Sudoeste sejam considerados mais resistentes ao estresse térmico quando comparados com corais recifais de outros oceanos, os fortes eventos registrados desde 2019 destacam a necessidade de monitoramento contínuo para entender melhor a dinâmica do branqueamento de corais e melhorar as previsões sobre os efeitos das mudanças globais na região.

The Parcel de Manuel Luis (PML) is located at the southern end of the Amazon Reef System, which comprises the northernmost reef formations of the Brazilian biogeographical province. Its unique position and singular seascape make the PML an important stepping-stone for marine organisms between the Brazilian and Caribbean provinces. Yet, due to its distance from the shore, high tidal amplitude, and strong currents associated with a series of pinnacles exposed during low spring tides, the PML is one of the least studied reefs in the Western South Atlantic. Here, we integrated sessile benthic community data, fish assemblage surveys, and remote filming of fish interactions to establish the most complete community assessment of the PML reefs to date. In our surveys, we documented 78 sessile benthic taxa, with a taxonomic dominance of macroalgae (54 taxa), including two new occurrences of sponges for the North Brazilian Shelf, as well as four endemic species, such as the fire coral Millepora laboreli. The fish assemblage comprised 59 reef fish species, with biomass dominated mainly by large carnivorous species (e.g., groupers and snappers). Intra- and interspecific interactions were dominated by herbivorous fishes, particularly underpinned by grazing behavior and chasing by territorial species. The considerably high biomass and large-bodied species found in our surveys is rarely seen elsewhere in the Western South Atlantic, suggesting a low level of fishing compared to most other places, and only a few changes were observed in the fish assemblages since the first assessment made in 1998. We also highlight the usefulness of an integrated approach for continued assessment of Western South Atlantic reefs, particularly given emerging threats from mining and oil exploration, and the heavy traffic of commercial vessels in the region. Our findings support the PML as an area of critical conservation interest for reef systems, emphasizing the need for continued enforcement of this marine protected area and its integration in long-term plans of offshore oil and gas development projects.

Brazil has a strong tradition in fisheries and is consequently affected by the impacts of this activity. Fishing-related debris, as abandoned, lost or otherwise discarded fishing gear (ALDFG) is an example of indirect impact. While reports on ALDFG are becoming more frequent worldwide, Brazil is still deficient in this information. The main objective of the present study was to review the knowledge on ALDFG in the country, as a contribution to the management of marine debris from fishing. The study also sought to investigate the number of scientific studies that report ALDFG, what sites were sampled and what are the knowledge gaps in this subject. An extensive literature review was carried out to obtain detailed information. Thirty-two studies were obtained from different fields of research reporting the presence of ALDFG in Brazil, with only nine focusing specifically on this topic. The most recorded items were nets, ropes and fishing lines found on beaches, submerged in coastal areas and in oceanic islands. The reports of ALDFG covered 12 of the 17 Brazilian coastal states, with significant presence of debris within protected areas. Overall there were few studies on the subject in Brazil. There are knowledge gaps regarding ALDFG in regions with depths greater than 45 m and distant 12 nautical miles from the coast, and regarding indirect impacts of ALDFG, such as habitat changes. Thus, more studies and actions are needed to minimize the occurrence of ALDFG in Brazil and to guarantee its inclusion in monitoring and management actions of protected areas.

Resource partitioning is considered one of the main processes driving diversification in ecological communities because it allows coexistence among closely related and ecologically equivalent species. We combined three complementary approaches, i.e. the evaluation of foraging behaviour, diet composition and nutritional condition (RNA:DNA ratio), to assess feeding by two closely related (sister) butterflyfishes that are syntopic in Puerto Rico. Chaetodon capistratus had a higher abundance and higher bite rate and selected octocorals and hard corals for feeding, whereas Chaetodon striatus fed preferentially on sandy substrates. Cnidarians and polychaetes were the most representative diet items for both species, but C. capistratus preferred the former (Feeding Index of 74.3%) and C. striatus the latter (Feeding Index of 60.4%). Similar RNA:DNA ratios for both species suggest that, although they differ in feeding rates and diet, C. capistratus and C. striatus have similar nutritional fitness. Therefore, these species are both zoobenthivores but show clear differences in their substrate selection. The differences in the use of foraging substrate by C. capistratus and C. striatus, despite their close phylogenetic relationship and similar diets, suggest that these species coexist by resource partitioning.

Brazil has the most extensive and richest areas of coral reefs in the South Atlantic Ocean, with its fauna characterized by high endemism and adaptations related to its growth and morphology, to its coral building fauna and to the depositional environment that differ from other coral reefs around the world. In spite of the effects from changes in the global environmental, the main stress factors for Brazilian reefs are local level threats, such as pollution and overfishing. The effects from these threats reduce biodiversity and result in decreasing stocks at different trophic levels. The trend that currently exists, regarding marine resource use, implies that reassessing the conservation strategies is urgently necessary if the degradation of these environments is to be reversed. It is necessary that the practices used in adjacent watersheds be improved, combined with actions to protect and recover native vegetation, along with planning for developing coastal areas, which will ensure that sedimentation rates be controlled and pollution sources are drastically reduced. Brazil should have to adopt a multidisciplinary approach to lead an evolution from traditional threat management in individual portions of ecosystems to large-scale management strategies in complex socio-economic and natural systems.

As marine ecosystems are influenced by global and regional processes, standardized information on community structure has become crucial for assessing broad-scale responses to natural and anthropogenic disturbances. Extensive biogeographic provinces, such as the Brazilian Province in the southwest Atlantic, present numerous theoretical and methodological challenges for understanding community patterns on a macroecological scale. In particular, the Brazilian Province is composed of a complex system of heterogeneous reefs and a few offshore islands, with contrasting histories and geophysical-chemical environments. Despite the large extent of the Brazilian Province (almost 8,000 kilometers), most studies of shallow benthic communities are qualitative surveys and/or have been geographically restricted. We quantified community structure of shallow reef habitats from 0° to 27°S latitude using a standard photographic quadrat technique. Percent cover data indicated that benthic communities of Brazilian reefs were dominated by algal turfs and frondose macroalgae, with low percent cover of reef-building corals. Community composition differed significantly among localities, mostly because of their macroalgal abundance, despite reef type or geographic region, with no evident latitudinal pattern. Benthic diversity was lower in the tropics, contrary to the general latitudinal diversity gradient pattern. Richness peaked at mid-latitudes, between 20°S to 23°S, where it was ~3.5-fold higher than localities with the lowest richness. This study provides the first large-scale description of benthic communities along the southwestern Atlantic, providing a baseline for macroecological comparisons and evaluation of future impacts. Moreover, the new understanding of richness distribution along Brazilian reefs will contribute to conservation planning efforts, such as management strategies and the spatial prioritization for the creation of new marine protected areas.

Here, we clarify the events described on a recent paper by Soares & Lucas in Marine Policy 93 (2018) that resulted in the establishment of large marine protected areas (MPAs) in Brazil. We describe crucial aspects of the planning process that were not addressed by the authors, particularly: (i) top-down changes on the original design that left the most diverse, unique and vulnerable ecosystems poorly protected; (ii) the permission of fishing activities within no-take areas; and (iii) shortfalls in using these MPAs for quantifying progress towards the Aichi Target 11. The spatial configuration of MPAs was modified by the government in a typical top-down scenario that received neither public nor scientific input. We call for a ban on fishing activities around the islands and on mining activities within all MPAs. We emphasize the need for reconciling qualitative aspects of Aichi Target 11 when establishing new MPAs as a strategy for enhancing conservation outcomes. The establishment of these large MPAs should not divert attention from actions needed for the protection of priority sites based on scientific evidence.

Mussismilia braziliensisis endemic to the south-western Atlantic, where it plays an important role as a major reef builder. It occurs in a wide range of sediment conditions between coastal and offshore environments. Here, we investigated its reproductive effort along an inshore–offshore gradient. Three sites were sampled with varying distances (15 to 60 km) from the mainland in the Abrolhos Reef Complex (18° S). Reproductive effort was estimated as fecundity (number of eggs per: polyp, cm2, mm3, and mesenteries). Mean fecundity per polyp was 338.7 (±73.5 SD) and the highest number of eggs per polyp was 987. Percentages of fertile mesenteries per polyp were similar among sites. However, the fecundity per mesentery varied among colonies and among sites. Fecundity per polyp increased as its area, volume, height and number of fertile mesenteries increases. The area closest to the coast (‘Pedra de Leste’) presented the highest mean fecundity per polyp (410 eggs ± 159.2 SD), cm2(233.47 eggs ± 219.44 SD), mm3(4.95 eggs ± 2.34 SD) and mesentery (10.6 eggs ± 4.3 SD). Corals closest to the coast had 55% higher fecundity per polyp and 64% higher fecundity per cm2than corals offshore. This area presented the highest contribution of non-carbonate sediments deposited on the reefs. Therefore, we suggest that colonies ofM. braziliensismay present higher uptake rates of particulate matter at inshore reefs, which allow for higher rates of tissue growth (less nutrient limitation) and energy allocation to reproduction.

Several reefs of the world have undergone changes in community due to sedimentation processes. It has been suggested that Abrolhos reefs (Brazil/South-West Atlantic) are subjected to a steady coastal influence, although there is still little information regarding this assumption. In this work, we have analyzed a set of environmental parameters concerning sedimentation characteristics at the Abrolhos reefs, near 18°S–39°W. The analysis included remote sensing, model and in situ data to provide a three-dimensional quantitative description of the processes that influence sediment apportionment to the reefs. Mineralogy and natural radioactivity of sediment trapped at three reef sites in a transect perpendicular to the coastline were used in conjunction with numerical weather prediction model and remote sensing databases. We have observed an increase of around 100% of sediment flux during the summer compared to the winter season. A comparison of regional rainfall regime, sediment plume dynamics and a year-around monitoring of polar fronts trajectories and surface wind showed that the wind-driven resedimentation due to polar front activity is the major contributor to the intensification of sedimentation processes at the offshore area of Abrolhos reefs, despite river runoff from mainland.

The feeding behaviour and diet plasticity of a given species are usually shaped by the relationship between species physiology and the quality and availability of resources in the environment. As such, some species may achieve wide geographical distributions by utilizing multiple resources at different sites within their ranges. We studied the distribution and feeding of Chaetodon striatus, the most widespread butterflyfish in the Atlantic, by assessing its density and foraging rates in eight sites enclosing 44 degrees of latitude. We also evaluated the relationship between fish density and foraging rates with nutritional condition and diet across study sites, and the gut length relative to body size. Density and foraging rates did not differ among studied sites. In 169 stomachs analysed, we found 52 different items (12-23 per site). Polychaeta and Cnidaria were the most important items in seven study sites. Therefore, C. striatus may be considered as a non-coral generalist feeder, as it feeds on a wide variety of items and substrata along the studied range, with no consistent selectivity pattern for foraging substratum across sites. Individuals from all sites but Salvador (NE Brazil) had similar RNA/DNA ratios, suggesting that C. striatus nutritional condition is similar along its extensive distribution. Our findings highlight the importance of assessing different sites within the distribution range of generalist butterflyfishes, and different variables, to a better comprehension of the feeding ecology of these species.

The Southwestern Atlantic harbors unique and relatively understudied reef systems, including the only atoll in South Atlantic: Rocas atoll. Located 230 km off the NE Brazilian coast, Rocas is formed by coralline red algae and vermetid mollusks, and is potentially one of the most “pristine” areas in Southwestern Atlantic. We provide the first comprehensive and integrative description of the fish and benthic communities inhabiting different shallow reef habitats of Rocas. We studied two contrasting tide pool habitats: open pools, which communicate with the open ocean even during low tides, thus more exposed to wave action; and closed pools, which remain isolated during low tide and are comparatively less exposed. Reef fish assemblages, benthic cover, algal turfs and fish feeding pressure on the benthos remarkably varied between open and closed pools. The planktivore Thalassoma noronhanum was the most abundant fish species in both habitats. In terms of biomass, the lemon shark Negaprion brevirostris and the omnivore Melichtys niger were dominant in open pools, while herbivorous fishes (mainly Acanthurus spp.) prevailed in closed pools. Overall benthic cover was dominated by algal turfs, composed of articulated calcareous algae in open pools and non-calcified algae in closed pools. Feeding pressure was dominated by acanthurids and was 10-fold lower in open pools than in closed pools. Besides different wave exposure conditions, such pattern could also be related to the presence of sharks in open pools, prompting herbivorous fish to feed more in closed pools. This might indirectly affect the structure of reef fish assemblages and benthic communities. The macroalgae Digenea simplex, which is uncommon in closed pools and abundant in the reef flat, was highly preferred in herbivory assays, indicating that herbivory by fishes might be shaping this distribution pattern. The variations in benthic and reef fish communities, and feeding pressure on the benthos between open and closed pools suggest that the dynamics in open pools is mostly driven by physical factors and the tolerance of organisms to harsh conditions, while in closed pools direct and indirect effects of species interactions also play an important role. Understanding the mechanisms shaping biological communities and how they scale-up to ecosystem functioning is particularly important on isolated near-pristine systems where natural processes can still be studied under limited human impact.

During fieldwork at the Abrolhos reefs (north-east Brazil) the whitespotted filefish Cantherhines macrocerus was observed predating a reproductive colony of the zoanthid Palythoa caribaeorum. Several fresh bite marks observed in the colonies suggest that other individuals and probably other species were also feeding on the zoanthid. This is the first record of predation on this zoanthid during its reproductive stage. Since P. caribaeorum contains anti-predation chemical defences, we discuss that the presence of egg-bearing polyps might increase the predator benefit in the predation trade-off, i.e. it might be more worthwhile to deal with such defences when the energy budget of eggs is also involved. Therefore, the reproductive stage of chemically defended organisms might shape the frequency and intensity of such interaction.

Submitted by Alberto Vieira (martins_vieira@ibest.com.br) on 2018-01-12T15:18:47Z No. of bitstreams: 1 618229.pdf: 11857723 bytes, checksum: 066ae99ab0cd60f237bc22b342b09d5b (MD5) Made available in DSpace on 2018-01-12T15:18:47Z (GMT). No. of bitstreams: 1 618229.pdf: 11857723 bytes, checksum: 066ae99ab0cd60f237bc22b342b09d5b (MD5) Previous issue date: 2003-04 CAPES Uma questão cada vez mais importante em recifes de coral de todo o mundo é o efeito dos sedimentos terrígenos sobre a biota recifal. O estudo teve por objetivo avaliar comunidades coralíneas sujeitas a diferentes condições de sedimentação no Banco dos Abrolhos. Os recifes internos do Banco apresentaram, quase sempre, taxas de sedimentação maiores que as dos recifes externos. As taxas de deposição na maioria dos recifes foram maiores no inverno-primavera e, na maioria das vezes, associadas à frequência de ventos de mais de 15 nós, provenientes de NE-E ou S. Isto e a observação de que a composição de radioisótopos no sedimento não variou entre as estações sugerem uma influência importante da ressuspensão no regime de sedimentação. As comunidades coralíneas não apresentaram relação direta com a taxa de deposição de sedimentos. No entanto, observou-se que, na maioria dos casos, recifes com alta cobertura de Palythoa caribaeorum também apresentaram alta deposição de sedimentos. Houve uma relação inversa entre cobertura de P. caribaeorum e cobertura coralínea. Apesar disso, recifes com comunidades e deposições de sedimento diversas apresentaram altas taxas de recrutamento de corais, e mesma incorporação de radioisótopos do sedimento pelo coral Mussismilia braziliensis. O recrutamento de hidrocorais apresentou correlação positiva com a abundância de adultos destes organismos, enquanto não foi observada esta relação entre recrutas e adultos de escleractíneos. Fatores relacionados à sedimentação, como a abundância de P. caribaeorum ou luz, podem estar influenciando indiretamente na estruturação das comunidades de corais. A ocorrência de comunidades diferentes em situações aparentemente semelhantes sugere que a estrutura das comunidades deve responder a uma complexa interação de fatores bióticos e abióticos, incluindo a ocorrência de eventos estocásticos. The effects of terrigenous sediments upon coral reefs are major concern all over the world. The aim of this study is to evaluate coral communities at different sediment settings at the Abrolhos Bank. Most reefs closer to shore presented higher sediment deposition rates than reefs farther from mainland. Deposition rates were, in most cases, higher at winter-spring and, usually, associated with the frequency of NE-E or S winds with speeds higher than 15 knots. This and the absence of differences in radioisotope composition of sediments in different seasons suggest an important influence of resuspention on the sedimentation regime. Coral communities showed no direct relation with sediment deposition. However, in most cases, reefs with high Palythoa caribaeorum cover also presented high sediment deposition rates. There was an inverse relation between P. caribaeorum abundance and coral cover. Nevertheless, reefs with different communities and sediment deposition rates presented high coral recruitment, and similar radioisotope assimilation by the coral Mussismilia braziliensis. Recruitment of hydrocorals presented a positive correlation with adult hydrocoral abundance, while scleractinian corais recruitment did not present the same pattern. Factors related to sedimentation, such as P. caribaeorum abundance or light, may be indirectly influencing the structure of coral communities. The occurence of different communities in apparently similar situations suggests these communities may respond to complex interactions of biotic and abiotic features, including the occurrence of stochastic events.

Submitted by Alberto Vieira (martins_vieira@ibest.com.br) on 2018-02-07T23:54:17Z No. of bitstreams: 1 278121.pdf: 8127899 bytes, checksum: 3473eb61a7feee420d01f0c085576985 (MD5) Made available in DSpace on 2018-02-07T23:54:17Z (GMT). No. of bitstreams: 1 278121.pdf: 8127899 bytes, checksum: 3473eb61a7feee420d01f0c085576985 (MD5) Previous issue date: 1998-08-28 CAPES FAPERJ FUJB A quantificação das comunidades coralíneas em três locais do Arquipélago dos Abrolhos, BA (Face Norte e Portinho, na Ilha de Santa Bárbara, e Ilha Siriba), foi realizada através de transectos de interseção de linha e de quadrados. Para as cinco espécies mais frequentes ou abundantes (Agaricia agaricites, Favia gravida, Mussismilia braziliensis, Porites branneri e Siderastrea stellata) foram avaliados os tamanhos e inclinações de colônias, distâncias entre ponto aleatório e colônias e entre colônias. Ao se comparar os resultados obtidos por quadrados e transectos, não se detectou diferença entre eles quanto à representação das comunidades ( contribuições de diferentes organismos para a cobertura da área). Entretanto, os transectos de interseção de linha detectaram um maior número de espécies, conferindo à amostra um maior poder de resolução do que o método de quadrados. Os organismos construtores dominantes em profundidades entre 1,9 e 4,0m são as algas calcáreas (12,3 a 19,5%) e o coral M braziliensis (1,8 a 24,5%). Foram demonstradas diversas diferenças significativas entre os três locais amostrados e, no caso da Ilha Siriba, entre estações de um mesmo local. As principais diferenças bióticas observadas entre os três locais se referem a cobertura total de corais, estruturação da comunidade a diferentes profundidades, parâmetros de diversidade, tamanhos de colônias e distâncias entre pontos aleatórios e colônias. Sugere-se que alguns destes fatores se devam a diferenças físicas entre os ambientes. The quantification of coral communities in three areas in the Abrolhos Archipelago (northern and southern inshore areas in Santa Bárbara Island, and Siriba Island) was performed using quadrats and intercept line transect methods. Colony size and inclination, the distances from random points to the nearest colony and between nearest colonies of the same species were evaluated for the five most frequent or abundant coral species (Agaricia agaricites, Favia gravida, Mussismilia braziliensis, Porites branneri e Siderastrea stellata). No differences were detected in the representation of the community (contributions of different organisms to coverage of an area) when the results of data from quadrats and transects were compared. However, intercept line transects detected more species, presenting higher resolution than quadrats. Dominant reef building organisms, between depths of 1.9 and 4.0 m, were calcareous algae (12.3 to 19.5%) and the coral M braziliensis (1.8 to 24.5%). Several significant differences were found among the three surveyed areas and, in Siriba Island, between different stations of a single area. The main biotic differences among the three areas referred to total coral cover, influence of depth in community structure variation, diversity parameters, colony sizes, and distances from random points to colonies. It is suggested that some of these factors may be affected by physical differences among the three environments.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq Interações competitivas entre organismos sésseis em ambientes recifais geralmente ocorrem através do contato físico, dada a limitação espacial nesses ambientes. O aquecimento dos oceanos é um dos fatores que podem afetar os resultados dessas interações, alterando a habilidade competitiva e o potencial de recuperação dos organismos. O Painel Intergovernamental sobre Mudanças Climáticas prevê em sua projeção com as maiores emissões de gases do efeito estufa um aumento médio na temperatura do Oceano Atlântico de 3 °C para o ano 2100. Millepora alcicornis é uma das únicas espécies de coral ramificado no Brasil, contribuindo para a complexidade estrutural no ambiente recifal. O zoantídeo Palythoa caribaeorum é um dos competidores de corais mais importantes do Atlântico Oeste. Ambas as espécies competem entre si desde a costa da Flórida até o Sudeste brasileiro. Se M. alcicornis suportar os 3 °C de aumento na temperatura, seguirá competindo com P. caribaeorum, pois esta, apesar de ter sua distribuição afetada, ainda ocorrerá em áreas recifais como o Caribe e o Nordeste brasileiro. Não se sabe como o aumento de temperatura afetará essa interação. Indo além de previsões da distribuição de espécies e levando em conta que interações também podem ser moduladas pelo aquecimento dos oceanos, estudamos a interação competitiva entre P. caribaeorum e M. alcicornis através de experimentos em campo e laboratório, abordando particularmente: o efeito do contato físico na saúde de M. alcicornis (campo e laboratório); o potencial de recuperação de M. alcicornis após o fim do contato (campo e laboratório); se essa interação é mediada por compostos químicos presentes na superfície de P. caribaeorum (campo e laboratório); e como o aquecimento do oceano pode afetar esses processos (laboratório; 27 °C vs. 30 °C). Descobrimos que o contato físico com P. caribaeorum causa mais danos do que com o seu controle em campo e em laboratório a 27 °C. A recuperação de M. alcicornis em laboratório a 27 °C e em campo ocorreu dentro de 10 dias. Algas filamentosas colonizaram a área de M. alcicornis que teve contato com P. caribaeorum em laboratório a 30 °C, dificultando sua capacidade de recuperação. O contato com o extrato químico de P. caribaeorum em laboratório a 27 °C e em campo causou mais danos a M. alcicornis do que o contato com seu controle. O contato com o extrato e seu controle causaram danos iguais a M. alcicornis em laboratório a 30 °C. Nossos resultados indicam que P. caribaeorum supera competitivamente M. alcicornis através de mecanismos físicos e químicos, e que um aumento de 3 °C na temperatura do oceano prejudica a recuperação de M. alcicornis e torna o aspecto físico do contato mais importante do que o aspecto químico. A taxa de sobrecrescimento de P. caribaeorum em M. alcicornis tende a subir com a intensificação dessa interação à medida que o oceano aquece, podendo levar à perda de complexidade estrutural e, consequentemente, de diversidade em recifes do Caribe e Brasil. Entender como o aquecimento dos oceanos pode afetar as interações competitivas é fundamental para projetarmos o futuro dos recifes. Competitive interactions between sessile organisms in reef environments generally occur through physical contact, given the spatial limitation in these environments. Ocean warming is one of the factors that can affect the outcomes of these interactions, changing the competitive ability and recovery capacity of the organisms. The Intergovernmental Panel on Climate Change predicts and average increase of 3 °C in the temperature of the Atlantic Ocean for the year 2100, under highest greenhouse gas emission projection. The hydrocoral Millepora alcicornis is one of the only branching coral species in Brazil, contributing to structural complexity in reef environments. The zoanthid Palythoa caribaeorum is one of the most important coral competitors in the Western Atlantic. Both species compete with each other from the coast of Florida to southeastern Brazil. If M. alcicornis withstands the 3 °C increase in temperature, it will continue to compete with P. caribaeorum, which will still occur in reef areas in the Caribbean and northeastern Brazil, despite minor distribution shifts. Going beyond predictions of species distribution, the effect of ocean warming on species interactions is poorly known. Because interactions can be modulated by ocean warming, we studied the competitive interaction between P. caribaeorum and M. alcicornis through field and laboratory experiments, addressing in particular: the effect of physical contact on the health of M. alcicornis (field and laboratory); the recovery potential of M. alcicornis after the end of contact (field and laboratory); whether this interaction is mediated by chemical compounds present on the surface of P. caribaeorum (field and laboratory); and how ocean warming can affect these processes (laboratory: 27 °C vs. 30 °C). We found that physical contact with P. caribaeorum causes more damage than with its control in the field and in the laboratory at 27 °C. The recovery of M. alcicornis in the laboratory at 27 °C and in the field occurred within 10 days. Filamentous algae colonized the area of M. alcicornis that had contact with P. caribaeorum in the laboratory at 30 °C, jeopardizing its recovery. Contact with chemical extract of P. caribaeorum in the laboratory at 27 °C and in the field caused more damage to M. alcicornis than contact with its control. Contact with the extract and its control caused equal damage to M. alcicornis in the laboratory at 30 °C. Our results indicate that P. caribaeorum outcompete M. alcicornis through physical and chemical mechanisms, and that an increase of 3 °C in the ocean temperature impairs the recovery of M. alcicornis and makes the physical aspect of contact more important than the chemical. The rate of P. caribaeorum overgrowth in M. alcicornis tends to increase with the intensification of this interaction as the ocean warms, which can lead to a loss of structural complexity and, consequently, of diversity in reefs in the Caribbean and Brazil. Understanding how ocean warming can affect competitive interactions in reef environments is essential to project the future of these ecosystems.

As comunidades bentônicas concentram a maior parcela da biodiversidade marinha e constituem um elemento essencial da estrutura dos ecossistemas marinhos como um todo. São vários os fatores que influenciam na dinâmica bentônica, como interações competitivas, reprodução, aporte de nutrientes, temperatura, entre outros. Esses fatores regem o funcionamento da comunidade e alterações desses padrões, como pesca e poluição, podem induzir mudanças de fase. Ainda assim, é possível que mudanças de fase façam parte da dinâmica natural, a partir de fenômenos que agem em escalas de tempo maiores. Por esse motivo, torna-se bastante difícil indicar quais fatores podem suscitar mudanças lentas que culminem em diferenças importantes na estrutura das comunidades. Portanto, se fazem necessários estudos de variações temporais de longo prazo para melhor entendimento desses padrões naturais e das mudanças nesses padrões, que podem afetar o funcionamento e a resiliência do ecossistema. Esse tipo de estudo ainda é escasso para ilhas oceânicas brasileiras, sendo mais frequentes estudos de caracterização e de curto prazo. Dada a importância desse tipo de pesquisa, o presente trabalho é o primeiro para a comunidade bentônica recifal de uma série de estudos de longo prazo na ilha da Trindade, e integra o \"Programa de Pesquisas Ecológicas de Longa Duração das Comunidades Recifais das ilhas Oceânicas Brasileiras\" (PELD-ILOC), com objetivo central de analisar a dinâmica espaço-temporal da comunidade bentônica da ilha da Trindade e descrever sua composição entre os anos de 2013 e 2017. Para tal, foram demarcados quatro sítios em torno da ilha, com três transecções de 20 metros de comprimento em cada um, amostrando uma transecção por profundidade com 10 fotoquadrados em cada transecção. A cobertura bentônica foi avaliada por meio do software CPCe, com identificação dos organismos até o menor nível taxonômico possível, sendo posteriormente agrupados em grupos morfofuncionais. No geral, a comunidade bentônica da ilha da Trindade no período analisado foi dominada por macroalgas (Caulerpa sp., Canistrocarpus cervicornis e Jania sp.), turf e algas calcárias crostosas (Peyssonnelia sp.) e apresenta diferença significativa entre sítios e anos, porém não apresenta diferenças significativas entre as profundidades analisadas. Apesar do dinamismo natural dessas comunidades, foi possível observar diminuição da abundância de organismos bioconstrutores em 2016, que pode ter ocorrido devido ao El-Niño registrado no mesmo período. O ano de 2017 foi o que menos se assemelhou com os demais, apresentando aumento na riqueza, maior diversidade, maior relação entre sítios, grande crescimento na abundância de algas calcárias crostosas e mudança de dominância dentro do grupo de macroalgas, com a substituição da macroalga Caulerpa sp. pela macroalga calcária articulada Jania sp.. Para explicar essas alterações, assim como suas consequências, é necessária a continuação do presente monitoramento, incluindo novas abordagens e metodologias, integrando análises de variáveis físico-químicas e padronização nos estudos para possíveis comparações, o que ajudaria a compreender melhor o comportamento da comunidade bentônica insular oceânica brasileira no geral e responder questões que só podem ser elucidadas a longo prazo. Benthic communities host a major fraction of the marine biodiversity, being an essential component in the structure of marine ecosystems. There are several factors that influence the benthic dynamics, such as competitive interactions, reproduction, nutrient, temperature, etc. These factors control the functioning of the community and changes in these patterns can induce phase shifts. Nevertheless, it is possible that phase shifts are part of the natural dynamics, from phenomena that act on larger time scales. So, it is very difficult to indicate which factors can lead to slow changes that affect the structure of communities. Therefore, studies of long-term temporal variations are needed to better understand changes in those patterns that may affect the functioning and resilience of the ecosystem. This kind of study is still scarce for Brazilian oceanic islands, with more frequent characterization and short-term assessments. Hence, the present work is the first one for the benthic reef community of a series of long-term studies in the Trindade Island, and integrates the \"Long-term Ecological Research Program of the Reef Communities of the Brazilian Oceanic Islands\" (in Portuguese Programa de Pesquisas Ecológicas de Longa Duração das Comunidades Recifais das Ilhas Oceânicas Brasileiras - PELD-ILOC). The present study describes and does a spatio-temporal analysis of the reef benthic community of Trindade Island, assessing the substrate cover dynamics of four sites from 2013 to 2017. Each site was sampled at three depth ranges, with three transects and ten photoquadrats in each transect. Benthic coverage was analyzed using the CPCe software, with organisms identified to the lowest possible taxonomic level, and later grouped into morphofunctional groups. In general, the benthic community of Trindade Island during the analyzed period was dominated by macroalgae (Caulerpa sp., Canistrocarpus cervicornis and Jania sp.), turf and crustose coralline algae (Peyssonnelia sp.) The results showed significant changes among sites and years, however did not show significant changes among depths. Despite the natural dynamism of these communities, it was possible to observe a decrease in the abundance of bioconstructors in the 2016 expedition, which may have occurred because to El-Niño during the same period. The year 2017 was the most different when compared to others years, with an increase in species richness, but also greater diversity, greater similarity among sites, and a pronounced growth in the abundance of crustose coralline algae. In the same year a change in the dominant species was also observed, with the substitution of the macroalgae Caulerpa sp. by the articulated coralline algae Jania sp.. It is important to continue the present monitoring in order to determine the main causes and consequences of these structural changes, including new approaches and methodologies, integrating abiotic variables and standardization in the studies for possible future comparisons, which would help to better understand the behavior of the Brazilian insular benthic oceanic community in general and answer questions that can only be elucidated in the long term.

Os recifes de coral estão entre os ambientes marinhos mais produtivos e ricos em biodiversidade. Esta biodiversidade está em parte associada a complexas estruturas formadas por corais escleractíneos. Apesar da importância ecológica, social e econômica dos recifes de corais, eles são expostos a várias ameaças relacionadas às atividades humanas. Dentre os impactos antrópicos em recifes, o branqueamento, ou perda de zooxantelas, é o mais notável e é diretamente relacionado à mortalidade dos corais. Por possuírem uma associação simbiótica com essas zooxantelas, alguns corais escleractíneos são considerados mixotróficos, caracterizados por modos de alimentação autotrófico (através de simbiose com o dinoflagelado Symbiodinium) e heterotrófico (predação sobre zooplâncton). Alguns estudos comprovam que corais com maior capacidade de alimentação heterotrófica são mais resistentes ao branqueamento e, consequentemente, às alterações climáticas. A fim de analisar se o coral escleractíneo Mussismilia hispida, é capaz de alternar seu modo nutricional entre predominante autotrófico e predominante heterotróficos, dezoito colônias foram amostradas ao longo de um ano. Marcadores Tróficos de Ácidos Graxos (FATM, na sigla em inglês) foram utilizados para determinar a fonte nutricional de carbono em tecido de corais. A concentração de células de Symbiodinium e a temperatura local também foram avaliadas. Branqueamento foi observado nos meses mais quentes do ano, quando a concentração de Symbiodinium diminuiu, voltando a aumentar nos meses mais frios. O marcador para dieta heterotrófica CGA (C20: 1ω9) foi encontrado em amostras de zooplâncton de toda a área de estudo. Em laboratório, colônias sem acesso a zooplâncton apresentaram perda significativa deste marcador após 10 dias. Amostras de colônias naturalmente branqueadas não apresentaram nenhum vestígio dos marcadores de autotrofia SDA (18: 4ω3) e DPA (22: 5ω3), mas continham tanto CGA e DHA (22: 6ω3). Isso confirmou que SDA e DPA são marcadores autotróficos viáveis e CGA é um marcador de heterotrofia. FATM relacionados com autotrofia apresentaram padrão semelhante ao observado para as concentrações de Symbiodinium e foram positivamente correlacionados com a densidade numérica de simbiontes e negativamente com a temperatura. Para explorar os dados de concentração dos FATM, o Índice Trófico de Corais foi desenvolvido para exibir as alternâncias entre modos nutricionais. Mussismilia hispida de fato alterna entre predominância de modo nutritivo ao longo do ano, sendo mais heterotrófica em períodos mais quentes e em condições climáticas adversas, porem na maior parte do ano é predominantemente autotrófica. A validação dos ácidos graxos marcadores tróficos específicos como referência para autotrofia e heterotrofia em corais abre perspectivas para novos estudos em ecologia trófica bêntica em recifes de coral. Este trabalho também inclui o primeiro monitoramento de um ano do comportamento alimentar em um coral hermatípico no Atlântico Sul e o acompanhamento de um evento de branqueamento. Coral reefs are among the most productive and biodiverse marine environments. This remarkable biodiversity is partly associated to the complex structures formed by scleractinian corals. Despite the ecological, social and economic importance of coral reefs, they are constantly exposed to several threats mainly related to human activities. Climate changes are one of the most notable impacts of human activity related to coral mortality, mainly due to coral bleaching. Some scleractinian corals are proved to be mixotrophs, displaying both autotrophic (through Symbiodinium) and heterotrophic (predation on zooplankton) nutrition modes. Many studies emphasize that corals with greater capability of heterotrophic feeding are more resilient to bleaching and consequently to climate change. In order to analyze whether the endemic scleractinian coral Mussismilia hispida is capable of shifting from predominant autotrophic and predominant heterotrophic in Ubatuba-SP, 18 colonies were sampled monthly for 12 months. The Fatty Acid Trophic Markers (FATM) approach was used to determine the source of carbon on coral tissues. Symbiodinium cell density and local seawater temperature were also assessed. A mild bleaching was observed showing a decrease in Symbiodinium numerical density during warmer months, but increasing in colder months. Reference samples validated the relation between all selected FATM and its corresponding nutritional mode. The heterotrophic feeding marker CGA (C20:1ω9) was found in zooplankton samples collected throughout the study area. Laboratory starved colonies (no access to zooplankton) lost any trace of this marker after 10. Samples from naturally bleached colonies presented no traces of the autotrophic feeding markers SDA (18:4ω3) and DPA (22:5ω3), but contained both CGA (C20:1ω9) and DHA (22:6ω3). These results confirmed that the FATM analyzed where reliable trophic markers. Autotrophic FATM presented a pattern similar to that observed for Symbiodinium concentration in M. hispida tissues and were positively correlated with the symbiont and negatively with temperature. The Coral Trophic Index showed that M. hispida undergoes shifts in nutritional modes along the year, being more heterotrophic in adverse conditions. The validation of specific FATM as proxies for autotrophic and heterotrophic feeding in corals opens new perspectives for further studies in benthic trophic ecology in coral reefs. This work also presents the first yearlong monitoring of the feeding behavior in a hermatypic coral in the South Atlantic and the monitoring of a mild bleaching event.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Os ecossistemas recifais proveem bens e serviços que abrangem as esferas social, ambiental e econômica. Contudo, cerca de 35% encontram-se ameaçados mundialmente. No Brasil, estão situados ao longo da região nordeste e geralmente próximos à costa, facilitando o acesso da população humana que utiliza-os para sustento e lazer. Para manter a resiliência e evitar a perda da biodiversidade torna-se importante estudar como ocorre o recrutamento e a sobrevivência dos seres vivos que estruturam as comunidades. O coral Siderastrea stellata, é um dos mais resistentes e comuns nos recifes brasileiros. Buscou-se entender aspectos da sua distribuição, recrutamento e manutenção das colônias. Para tal, efetuou-se mapeamento das colônias por tamanho em diferentes sítios de estudo no Parracho de Pirangi/RN, experimento de recrutamento com manipulação de rodolitos e experimento de avaliação da saúde de colônias com manipulação de macroalgas bênticas. Com o mapeamento observou-se uma zonação das colônias, com menos corais ocorrendo próximo ao local destinado à atividade turística. Possivelmente impactos como a constante suspensão de sedimentos provocada por banhistas e embarcações esteja agindo como o mecanismo condutor desta zonação. O recrutamento de corais foi baixo comparado a outros recifes rasos do nordeste brasileiro. Embora muito resistente, o coral S. stellata não está conseguindo se estabelecer nesta formação recifal. Notou-se que o recrutamento não é facilitado por rodolitos. Bancos de rodolitos abrigam alta riqueza de invertebrados bentônicos que podem competir por espaço ou se alimentar das larvas de corais. De modo geral, a saúde das colônias jovens foi afetada pelo branqueamento, que aumentou ao longo ano. Este aumento foi correlacionado com hipossalinidade e elevada turbidez da água. Porém, notou-se que na presença das macroalgas bênticas o branqueamento foi menor. Possivelmente o crescimento dessas macroalgas dentro do limite observado atenuou o efeito da elevada radiação solar nas colônias jovens de corais, protegendo-as do branqueamento. Reef ecosystems are known worldwide for their natural beauty and their capacity to harbor a great variety of marine life. In addition, these environments provide goods and services that encompasses social, environmental and economic spheres. However, around 20% of the world's reefs have been destroyed and 35% are threatened. In Brazil, the reefs are located along the northeast region and are usually near the coast, enabling the access of the human populations that use them for food, sport and recreation. One way to maintain reef resilience and avoid biodiversity loss would be to gather information on recruitment and survival of organisms from reef communities. The endemic hard coral, Siderastrea stellata, is one of the most resistant and common species in Brazilian reefs. Considering the ecological importance of this species of coral, we aimed to understand some aspects of its distribution, recruitment and colony maintenance. Therefore, S. stellata colonies were analyzed at different study sites in the “Parracho de Pirangi/RN”. The following activities were performed: 1) mapping colonies size (Chapter 1), 2) running recruitment experiment subjected to manipulation of calcareous algae (rhodoliths), testing the hypothesis that rhodoliths act as facilitators due its complex three-dimensional structure (Chapter 2), and 3) running a health evaluation experiment of juvenile colonies in different areas of the reef, through macroalgae manipulation, testing the hypothesis that coral colony health is affected negatively by the presence of benthic macroalgae (Chapter 3). A distribution pattern in Parracho de Pirangi/RN was observed with less coral occurring in the area nearby touristic site. It is possible that impacts such as the constant suspension of sediments caused by swimmers and boats are acting as the main mechanism driving this distribuition pattern. Coral recruitment of Parracho de Pirangi was low compared to other shallow reefs from northeastern Brazil. This shows that although very resistant, the coral S. stellata is not able to establish on this reef formation. It was also noted that recruitment is not facilitated by calcareous algae that form rhodoliths. Instead, rhodolith banks sheltered abundant concentration of benthic invertebrates that might compete for space or feed on coral larvae, preventing recruitment. Generally, the health of young colonies was affected by bleaching, which increased throughout the year. This increase was correlated with low water salinity registered. However, it was notable that bleaching was lower in the treatment where benthic macroalgae was not removed. Possibly, the growth of benthic macroalgae within the limits observed over the months attenuated the effects of high solar radiation on young coral colonies, protecting them from bleaching.