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1.
Environ Res ; 248: 118240, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38266903

RESUMEN

Monitoring of contaminant levels in wildlife over time is a tool for assessing the presence and persistence of environmental impacts at ecosystem, community and population levels. Tropical seabirds breeding in the Abrolhos Archipelago, 70 km off the Brazilian coast, forage in areas under the influence of the Doce River discharge. In 2015, the Fundão Dam collapsed and released ca 60 million tons of iron ore tailings into the ocean. In the present study, red-billed tropicbirds Phaethon aethereus and brown boobies Sula leucogaster breeding in Abrolhos were monitored over four years (2019-2022) for metal (Fe, Mn, Zn, Cu, Cr, Hg, Pb, Cd) and metalloid (As) concentrations in blood and feathers. Over six sampling events, metal (loid) concentrations showed strong temporal variation in both tissues. Overall, feathers showed greater element concentrations than blood, with stronger correlations between elements, especially Mn and the nonessential As, Cd, Hg and Pb. Mn is one of the major chemical markers of the Fundão Dam tailings. Metal (loid) concentrations in the tropical seabirds evaluated were above suggested threshold levels for most nonessential elements (As, Cd and Pb), especially in February 2021, when metal (loid) concentrations peaked in feathers. In this case, values were orders of magnitude higher than those observed in other sampling events. This occurred one year after a major rainy season in the Doce River basin, which increased river discharge of contaminated mud into the ocean, where contaminants are further remobilized by winds and currents, resulting in transference through the marine food web. This finding is consistent to what has been observed for other ecosystem compartments monitored in the region under the influence of the Doce River. Our findings highlight the utility of using tropical seabirds as sentinels of marine pollution, revealing strong temporal patterns in metal (loid) concentrations associated to bottom-up climatic processes.


Asunto(s)
Arsénico , Desastres , Mercurio , Contaminantes Químicos del Agua , Animales , Arsénico/análisis , Ecosistema , Plumas , Cadmio , Plomo , Monitoreo del Ambiente/métodos , Aves , Brasil , Ríos , Contaminantes Químicos del Agua/análisis
2.
J Fish Biol ; 99(4): 1292-1298, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34180056

RESUMEN

In this study, a new species of Pseudogilbia Møller, Schwarzhans & Nielsen 2004 is described based on two male specimens (40-44 mm LS ) from shallow reefs of Bahia, Brazil. Pseudogilbia australis sp. nov. is distinguished from its only congener, Pseudogilbia sanblasensis Møller, Schwarzhans & Nielsen 2004 from Caribbean Panama, by having: two lower preopercular pores (vs. one); dorsal-fin rays 65-67 (vs. 69); anal-fin rays 51-53 (vs. 56); pectoral-fin rays 18 (vs. 20); caudal vertebrae 27-28 (vs. 30); pectoral-fin length 15.0%-15.9% LS (vs. 14.3); pelvic-fin length 13.5% LS (vs. 16.4) and a different morphology of the male copulatory organ. Pseudogilbia australis sp. nov. is the only dinematichthyid so far recorded in the South Atlantic. An updated diagnosis for the genus is also provided.


Asunto(s)
Perciformes , Animales , Brasil , Región del Caribe , Peces , Masculino , Panamá
3.
Microb Ecol ; 80(2): 249-265, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32060621

RESUMEN

Turfs are among the major benthic components of reef systems worldwide. The nearly complete genome sequences, basic physiological characteristics, and phylogenomic reconstruction of two phycobiliprotein-rich filamentous cyanobacteria strains isolated from turf assemblages from the Abrolhos Bank (Brazil) are investigated. Both Adonisia turfae CCMR0081T (= CBAS 745T) and CCMR0082 contain approximately 8 Mbp in genome size and experiments identified that both strains exhibit chromatic acclimation. Whereas CCMR0081T exhibits chromatic acclimation type 3 (CA3) regulating both phycocyanin (PC) and phycoerythrin (PE), CCMR0082 strain exhibits chromatic acclimation type 2 (CA2), in correspondence with genes encoding specific photosensors and regulators for PC and PE. Furthermore, a high number and diversity of secondary metabolite synthesis gene clusters were identified in both genomes, and they were able to grow at high temperatures (28 °C, with scant growth at 30 °C). These characteristics provide insights into their widespread distribution in reef systems.


Asunto(s)
Cianobacterias/fisiología , Genoma Bacteriano/fisiología , Océano Atlántico , Brasil , Arrecifes de Coral , Cianobacterias/genética , Filogenia
4.
J Fish Biol ; 95(5): 1346-1349, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31490544

RESUMEN

The snow bass Serranus chionaraia is a small-bodied reef fish presumed to be restricted to the Caribbean Province, with a single specimen captured south of the Amazon River mouth. Recent surveys with baited remote underwater stereo-video systems detected the species c. 1900 km southward. Meristic and morphometric characters of two specimens examined in this study confirmed the species identity, which greatly extends the species' range southward on the eastern coast of Brazil and indicates the presence of an established population of S. chionaraia in the Brazilian Province.


Asunto(s)
Perciformes/fisiología , Distribución Animal , Animales , Brasil , Densidad de Población , Dinámica Poblacional
5.
Conserv Biol ; 32(5): 1096-1106, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-28646574

RESUMEN

Although marine protected areas can simultaneously contribute to biodiversity conservation and fisheries management, the global network is biased toward particular ecosystem types because they have been established primarily in an ad hoc fashion. The optimization of trade-offs between biodiversity benefits and socioeconomic values increases success of protected areas and minimizes enforcement costs in the long run, but it is often neglected in marine spatial planning (MSP). Although the acquisition of spatially explicit socioeconomic data is perceived as a costly or secondary step in MSP, it is critical to account for lost opportunities by people whose activities will be restricted, especially fishers. We developed an easily reproduced habitat-based approach to estimate the spatial distribution of opportunity cost to fishers in data-poor regions. We assumed the most accessible areas have higher economic and conservation values than less accessible areas and their designation as no-take zones represents a loss of fishing opportunities. We estimated potential distribution of fishing resources from bathymetric ranges and benthic habitat distribution and the relative importance of the different resources for each port of total catches, revenues, and stakeholder perception. In our model, we combined different cost layers to produce a comprehensive cost layer so that we could evaluate of trade-offs. Our approach directly supports conservation planning, can be applied generally, and is expected to facilitate stakeholder input and community acceptance of conservation.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Biodiversidad , Costos y Análisis de Costo , Explotaciones Pesqueras
6.
J Fish Biol ; 91(2): 686-694, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28776707

RESUMEN

The reproductive biology of Centropomus pectinatus is described from an artisanal fish landings collaborative monitoring programme between May 2012 and April 2013 in estuarine waters in north-eastern Brazil. The total length (LT ) at which 50% are mature was 24 cm, corresponding to 37·7% of the maximum recorded LT . Gonado-somatic indices were variable, but highest values were in June and August 2012. Length-frequency distributions showed male dominance in smaller length classes (15-30 cm) and females in larger length classes (>30 cm).


Asunto(s)
Perciformes/fisiología , Reproducción , Animales , Océano Atlántico , Tamaño Corporal , Brasil , Femenino , Explotaciones Pesqueras , Masculino , Perciformes/anatomía & histología , Perciformes/crecimiento & desarrollo , Estaciones del Año , Maduración Sexual
7.
J Fish Biol ; 90(5): 2111-2124, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28321878

RESUMEN

The reproductive biology of the white grunt Haemulon plumierii was studied from 360 individuals obtained from artisanal fisheries landings in the Abrolhos Bank, Brazil, between August 2010 and March 2012. The overall sex-ratio did not differ significantly from 1:1, although males predominated in larger size classes. ß-Binomial modelling of historical sex-ratio data indicated that the catch rate of females has increased in recent years. Females reached maturity at a smaller total length (LT ; 214 mm) than males (235 mm LT ) and the LT at which 50% of all individuals are mature (L50 ) was 220 mm, corresponding to 41·5% of the maximum recorded LT . Variation in the gonado-somatic index and in the relative frequency of reproductive stages indicates that reproduction occurs year round, with increased activity during the austral spring and summer. Fecundity was not size dependent. The reproductive parameters provided here can support management measures focussed on seasonal closures during spawning peaks (September to November and February to March) and minimum sizes (>L50 ) for the capture of this important artisanal fisheries resource in Abrolhos, the region with the largest and most biodiverse coralline reefs in the South Atlantic Ocean.


Asunto(s)
Explotaciones Pesqueras , Peces/fisiología , Reproducción/fisiología , Distribución Animal , Animales , Océano Atlántico , Femenino , Peces/clasificación , Masculino , Modelos Estadísticos , Dinámica Poblacional , Estaciones del Año , Razón de Masculinidad
8.
Mol Ecol ; 25(18): 4632-44, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27492757

RESUMEN

Infectious diseases such as white plague syndrome (WPS) and black band disease (BBD) have caused massive coral loss worldwide. We performed a metaproteomic study on the Abrolhos coral Mussismilia braziliensis to define the types of proteins expressed in healthy corals compared to WPS- and BBD-affected corals. A total of 6363 MS/MS spectra were identified as 361 different proteins. Healthy corals had a set of proteins that may be considered markers of holobiont homoeostasis, including tubulin, histone, Rab family, ribosomal, peridinin-chlorophyll a-binding protein, F0F1-type ATP synthase, alpha-iG protein, calmodulin and ADP-ribosylation factor. Cnidaria proteins found in healthy M. braziliensis were associated with Cnidaria-Symbiodinium endosymbiosis and included chaperones (hsp70, hsp90 and calreticulin), structural and membrane modelling proteins (actin) and proteins with functions related to intracellular vesicular traffic (Rab7 and ADP-ribosylation factor 1) and signal transduction (14-3-3 protein and calmodulin). WPS resulted in a clear shift in the predominance of proteins, from those related to aerobic nitrogen-fixing bacteria (i.e. Rhizobiales, Sphingomonadales and Actinomycetales) in healthy corals to those produced by facultative/anaerobic sulphate-reducing bacteria (i.e. Enterobacteriales, Alteromonadales, Clostridiales and Bacteroidetes) in WPS corals. BBD corals developed a diverse community dominated by cyanobacteria and sulphur cycle bacteria. Hsp60, hsp90 and adenosylhomocysteinase proteins were produced mainly by cyanobacteria in BBD corals, which is consistent with elevated oxidative stress in hydrogen sulphide- and cyanotoxin-rich environments. This study demonstrates the usefulness of metaproteomics for gaining better comprehension of coral metabolic status in health and disease, especially in reef systems such as the Abrolhos that are suffering from the increase in global and local threatening events.


Asunto(s)
Antozoos/genética , Antozoos/microbiología , Bacterias/clasificación , Animales , Brasil , Proteómica , Simbiosis , Espectrometría de Masas en Tándem
9.
Sci Total Environ ; 891: 164465, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37247740

RESUMEN

Microbes play a central role in coral reef health. However, the relative importance of physical-chemical and biological processes in the control of microbial biomass are unknown. Here, we applied machine learning to analyze a large dataset of biological, physical, and chemical parameters (N = 665 coral reef seawater samples) to understand the factors that modulate microbial abundance in the water of Abrolhos reefs, the largest and richest coral reefs of the Southwest Atlantic. Random Forest (RF) and Boosted Regression Tree (BRT) models indicated that hydrodynamic forcing, Dissolved Organic Carbon (DOC), and Total Nitrogen (TN) were the most important predictors of microbial abundance. The possible cumulative effects of higher temperatures, longer seawater residence time, higher nutrient concentration, and lower coral and fish biomass observed in coastal reefs resulted in higher microbial abundance, potentially impacting coral resilience against stressors.


Asunto(s)
Antozoos , Arrecifes de Coral , Animales , Biomasa , Calor , Aprendizaje Automático
10.
Sci Total Environ ; 697: 134038, 2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-32380596

RESUMEN

On November 5th, 2015, the Fundão dam rupture released >50 million m3 of ore tailings into the Doce River, Minas Gerais State, Brazil. The huge volume of mud spread along the river and reached the sea, 17 days after the disaster, in Regência, Espírito Santo State (ES). In 2018, after three years of the disaster, the impacts of the ore tailings in the marine environment are still unclear. This study aims to investigate possible short-term impacts in marine biodiversity caused by the ore tailings' mud over the reef ecosystems that are closest to the disaster area: i.e. recently discovered reefs in the southern Abrolhos Bank. A remote sensing surveillance including winds, sea surface temperature, total suspended material and watercolor (MODIS Aqua data) indicated that the iron tailings plume reached the southern portion of Abrolhos Bank on June 16th, 2016. Subsequently, to obtain further evidence of the presence of the tailings in the coral reefs, water samples were collected in a gradient spanning from the river estuary to the reefs in southern Abrolhos Bank, we also analyzed the isotopic and microbial composition of the samples, as well as the reef benthic composition. Despite no clues of negative impact on benthic (coral) communities, isotopic analysis confirmed the presence of the plume over the reefs area. This study serves as a baseline for future long-term impact assessments of the health of coral reefs in the Abrolhos Bank.


Asunto(s)
Arrecifes de Coral , Metagenómica , Tecnología de Sensores Remotos , Ríos/química , Contaminantes del Agua/análisis , Animales , Antozoos , Brasil , Ecosistema , Isótopos/análisis
11.
Mar Pollut Bull ; 114(1): 123-133, 2017 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-27641110

RESUMEN

The Abrolhos Bank is an area of high ecological, socio-economic importance and harbour the richest and most-extensive coral reefs in the South Atlantic. Here we report the discovery of shallow (12-25m depth) reef complex with ten large biogenic structures, intermediate between the typical mushroom-shaped pinnacles of the northern Abrolhos Bank (17°-18° S) and the small patch reefs found on the central/southern coast of the Espírito Santo State (19°-20° S). The newly discovered reefs harbour a relatively rich and abundant reef community, with 73 fish and 14 benthic cnidarian species, including endangered and commercially important ones. We discuss on urgent needs of properly mapping and understanding the ecological functioning of this reef system. Information provided here is a baseline for future impact evaluations, particularly considering the recent worst environmental disaster of Brazil from a dam collapse in Doce river that affected the region.


Asunto(s)
Conservación de los Recursos Naturales , Arrecifes de Coral , Animales , Antozoos/crecimiento & desarrollo , Brasil , Ecología , Ambiente , Peces , Contaminación del Agua/prevención & control , Contaminación del Agua/estadística & datos numéricos
12.
Neotrop. ichthyol ; 15(2): e160047, 2017. tab, graf, mapas
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-841890

RESUMEN

Red and black groupers are large-bodied opportunistic ambush predators commonly found in Southwestern Atlantic tropical reefs. We investigated the diet of both species in order to detail ontogenetic, spatial and temporal trends, and to assess the extent of overlap in resource use between these two sympatric predators on the Abrolhos Bank, Brazil. Decapods and fishes were the main food items of Epinephelus morio while fishes were the main prey of Mycteroperca bonaci. Both diets were significantly influenced by body size and habitat, but only smaller individuals of E. morio feed almost exclusively on crustaceans. While the two groupers rely on many of the same prey types, coexistence may be facilitated by E. morio feeding more heavily on crustaceans, particularly the blackpoint sculling crab Cronius ruber, while black grouper take comparatively few crustaceans but lots of fish prey. Predators like red and black groupers could trigger indirect effects in the community and influence a large range of ecological processes, such as linkages between top and intermediate predators, and intermediate predators and their resources.(AU)


A garoupa e o badejo-verdadeiro são predadores oportunistas de grande porte, com estratégia de emboscada, comumente encontrados em recifes tropicais do Atlântico Sul. A dieta das duas espécies foi investigada, avaliando influências ontogenéticas, espaciais e temporais, assim como a sobreposição no uso de recursos entre estes dois predadores co-orrentes no Banco dos Abrolhos, Brasil. Decápodes e peixes foram os principais itens alimentares de Epinephelus morio, enquanto que os peixes foram as principais presas de Mycteroperca bonaci. Ambas as dietas foram significativamente influenciadas pelo tamanho corporal e habitat, mas apenas indivíduos menores de E. morio alimentaram-se quase que exclusivamente de crustáceos. Como as duas espécies utilizam muitas presas semelhantes, a coexistencia parece ser facilitada pelo fato de E. morio se alimentar principalmente de crustáceos, particularmente do caranguejo Cronius ruber, enquanto que o badejo-verdadeiro consome relativamente poucos crustáceos e grande quantidade de peixes. Predadores como as espécies estudadas podem causar efeitos indiretos na comunidade e influenciar uma grande variedade de processos ecológicos, como conexões entre predadores de topo e intermediários e predadores intermediários e seus recursos.(AU)


Asunto(s)
Animales , Ecología de la Nutrición , Perciformes/clasificación , Cadena Alimentaria , Ingestión de Alimentos
13.
Neotrop. ichthyol ; 14(2): e150103, 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-785080

RESUMEN

Coastal hammerheads have suffered from overexploitation and environmental degradation. We interviewed 79 artisanal fishers to verify fishery aspects, temporal changes in catches and biological aspects of the smalleye hammerhead, Sphyrna tudes , in a marine protected area on Abrolhos Bank, Brazil. Data were compared between three generations of fishers: young, middle-aged and old. Fishers' age varied between 17 and 88 years. We verified significant reductions in the weight of individuals caught by younger fishers. The main types of fishing gear used to catch S. tudes were gill nets and longlines. Overfishing through gill nets and trawl fisheries were mentioned as the cause of S. tudes population collapse in the region. The shark's diet as reported by fishers consisted of fish, crab and shrimp; austral summer was the reproductive season. A strong similarity was verified between fishers' knowledge and biological data. We suggest as plausible strategies to conserve the local population of S. tudes the reduction of net fisheries impact through zoning and establishment of no take areas. These steps can help to initiate the recovery of this depleted species.


Tubarões martelo costeiros têm sofrido com a sobrepesca e degradação ambiental. Foram entrevistados 79 pescadores artesanais para verificar aspectos da pesca, mudanças temporais nas capturas e aspectos biológicos de Sphyrna tudes em uma área marinha protegida no Banco dos Abrolhos, Brasil. Os dados foram comparados entre três gerações de pescadores: novos, meia idade e mais velhos. A idade dos pescadores variou entre 17 e 88 anos. Verificaram-se reduções significativas no peso dos indivíduos capturados pelos pescadores mais jovens. Os principais petrechos usados para captura de S. tudes foram redes de emalhe e espinhel. Pescadores mencionaram que o colapso da população local de S. tudes foi decorrente do excessivo uso de redes de emalhe e pelas pescarias de arrasto. A dieta reportada foi peixes, caranguejos e camarões e a época de reprodução foi o verão. Uma forte similaridade foi verificada entre o conhecimento dos pescadores e dados biológicos. São sugeridas como estratégias plausíveis para conservar a população local de S. tudes a redução do esforço das pescas com rede através de zoneamento e estabelecimento de áreas de exclusão de pesca. Esses passos podem ajudar a iniciar a recuperação de espécies depletadas.


Asunto(s)
Animales , Estuarios/clasificación , Tiburones/crecimiento & desarrollo , Fenómenos Ecológicos y Ambientales
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