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Abstract The Atlantic goliath grouper Epinephelus itajara is the largest grouper species in the Atlantic Ocean. Despite the conservation status being Vulnerable (VU) globally and Critically Endangered (CR) in Brazil, the species continues to face threats from overfishing throughout its range. We used DNA barcoding employing the mitochondrial Cytochrome c oxidase subunit I (COI) gene to identify the illegal commercialization of E. itajara in fish markets from the northern (NC) and southern (SC) Brazilian coasts. Sampling was conducted in fish markets and aimed to confirm the identification of mischaracterized fish sold as E. itajara in the NC, as well as identifying fish fillets sold as the Dusky grouper in the SC. DNA barcoding allowed the unambiguous identification of 22 (84.6%) of the 26 analyzed fish market samples. Both sampled areas had confirmation of E. itajara illegal commercialization and from the 22 analyzed samples, 17 (77.3%) were confirmed to be E. itajara. Here we report two crimes, the illegal sale of E. itajara and commercial fraud by species substitution. This study has highlighted that the existing legislation that protects E. itajara in Brazilian waters requires the adoption of better public policies for the conservation of the species.

ABSTRACT 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.

We determined the age and growth of the dog snapper (Lutjanus jocu), caught in the region of Abrolhos Bank, Bahia State, by the fishermen from coastal communities of Prado, Alcobaça, Caravelas, and Nova Viçosa. We examined 205 sectioned otoliths of fish caught by harpoon, longline, hand line, and gill nets (14.5 to 79.5 cm fork length). The formation of each ring was considered annual. The sectioned otoliths showed between 0 and 29 rings. Nearly half of the analyzed specimens had between 0 and 7 rings (88 of 205). Fish caught with nets in the estuarine region were the juvenile, while fish caught with lines and harpoons were the oldest. Two von Bertalanffy growth models were fitted to length-at-age data: one assuming constant variance of length-at-age (SVB) and another assuming constant coefficient of variation, i.e. variance increasing as a function of average size (CVVB). The SVB estimates were Loo = 87.82 cm, K = 0.10, and t0 = -1.486 and the CVVB estimates were Loo = 117.60 cm, K = 0.06, and t0 = -2.470. The largest Loo values estimated by the CVVB model are supported by reports from the literature of larger animals occurring in the deeper outer shelf of Abrolhos Bank. Growth parameters were also estimated for males and females separately (SVB model) (Loo = 92.80 cm, K = 0.099, and t0 = -1.680 for males, and Loo = 82.10 cm, K = 0.105, and t0 = -1.570 for females).Foi determinada a idade e o crescimento do dentão (Lutjanus jocu) capturado na região do Banco dos Abrolhos, Bahia, pelos pescadores das comunidades costeiras de Prado, Alcobaça, Caravelas e Nova Viçosa. Foram examinados 205 otólitos seccionados de peixes capturados por arpão, espinhel de fundo, linhas e redes de emalhe (14,5-79,5 cm comprimento furcal). A formação de cada anel foi considerada anual. Os otólitos seccionados apresentaram entre 0 e 29 anéis. Cerca de metade dos espécimes analisados teve entre 0 e 7 anéis (88 de 205). Os peixes capturados com redes na região estuarina foram os mais jovens enquanto os peixes capturados com arpões e linha foram os mais velhos. Dois modelos de crescimento de von Bertalanffy foram ajustados aos comprimentos individuais: um assumindo variância constante do comprimento em cada idade (SVB) e outro assumindo coeficiente de variação constante, isto é variância aumentando em função do tamanho médio (CVVB). As estimativas SVB foram (Loo = 87,82 cm, K = 0,105 e t0 = -1,486) e as estimativas CVVB foram Loo = 117,60 cm, K = 0,060 e t0 = -2,470). Os maiores valores de Loo estimados pelo modelo CVVB são sustentados por relatos da literatura de grandes animais encontrados em áreas mais profunda do Banco dos Abrolhos. Os parâmetros de crescimento também foram estimados para machos e fêmeas separadamente (modelo SVB), (Loo = 92,80 cm, K = 0,099 e t0 = -1,680 para machos e Loo = 82,10 cm, K = 0,105 e t0 = -1,570 para fêmeas).

Diet and feeding ecology of the mutton snapper Lutjanus analis were investigated in the Abrolhos Bank, Eastern Brazil, the largest and richest coral reefs in the South Atlantic, where about 270 species of reef and shore fishes occur. To evaluate seasonal and ontogenetic shifts in the diet, specimens of L. analis were obtained through a fish monitoring program in four cities in southern Bahia State, from June 2005 to March 2007. Stomachs from 85 mutton snappers that ranged in size from 18.1 to 74.0 cm TL were examined. Prey were identified to the lowest possible taxon and assessed by the frequency of occurrence and volumetric methods. Variations in volume prey consumption were evaluated using non-metric multi-dimensional scaling ordination, analysis of similarity, and similarity percentage methods. Significant differences in diet composition among size classes were registered, whereas non significant differences between seasons were observed. Considering size-classes, food items consumption showed important variations: juveniles (50.1 cm TL) consumed basically fish, mostly Anguiliformes. Lutjanus analis is an important generalist reef predator, with a broad array of food resources and ontogenetic changes in the diet. This snapper species plays an important role on the trophic ecology of the Abrolhos Bank coral reefs.Foram avaliadas a dieta e a ecologia alimentar da cioba Lutjanus analis no Banco dos Abrolhos, Leste do Brasil. O Banco dos Abrolhos abrange os maiores e mais diversos recifes de corais do Atlântico Sul, onde cerca de 270 espécies de peixes recifais e costeiros ocorrem. Para a avaliação das variações sazonais e ontogênicas na dieta, exemplares de L. analis foram obtidos através de um programa de monitoramento em quatro cidades do extremo sul da Bahia, entre junho de 2005 e março de 2007. Estômagos de 85 exemplares com comprimento total variando entre 18,1 e 74,0 cm foram examinados. Os itens alimentares foram identificados até o menor nível taxonômico possível e avaliados através dos métodos de frequência de ocorrência e volumétrico. Variações no consumo das presas foram avaliadas através do método de escalonamento multidimensional não-métrico e métodos de análise de similaridade e percentagem de similaridade. Diferenças significativas na dieta foram observadas entre as classes de tamanho, porém estas não foram detectadas entre as estações do ano. Considerando as classes de tamanho, os itens consumidos apresentaram importantes variações: os juvenis (50,1 cm CT) consumiram basicamente peixes, principalmente Anguiliformes. Lutjanus analis é um importante predador recifal generalista, que consome um amplo espectro de presas, apresentando mudanças ontogênicas na dieta. Esse lutjanídeo desempenha um importante papel na ecologia trófica dos recifes de corais do Banco dos Abrolhos.

We determined the age and growth of the dog snapper (Lutjanus jocu), caught in the region of Abrolhos Bank, Bahia State, by the fishermen from coastal communities of Prado, Alcobaça, Caravelas, and Nova Viçosa. We examined 205 sectioned otoliths of fish caught by harpoon, longline, hand line, and gill nets (14.5 to 79.5 cm fork length). The formation of each ring was considered annual. The sectioned otoliths showed between 0 and 29 rings. Nearly half of the analyzed specimens had between 0 and 7 rings (88 of 205). Fish caught with nets in the estuarine region were the juvenile, while fish caught with lines and harpoons were the oldest. Two von Bertalanffy growth models were fitted to length-at-age data: one assuming constant variance of length-at-age (SVB) and another assuming constant coefficient of variation, i.e. variance increasing as a function of average size (CVVB). The SVB estimates were Loo = 87.82 cm, K = 0.10, and t0 = -1.486 and the CVVB estimates were Loo = 117.60 cm, K = 0.06, and t0 = -2.470. The largest Loo values estimated by the CVVB model are supported by reports from the literature of larger animals occurring in the deeper outer shelf of Abrolhos Bank. Growth parameters were also estimated for males and females separately (SVB model) (Loo = 92.80 cm, K = 0.099, and t0 = -1.680 for males, and Loo = 82.10 cm, K = 0.105, and t0 = -1.570 for females).

Diet and feeding ecology of the mutton snapper Lutjanus analis were investigated in the Abrolhos Bank, Eastern Brazil, the largest and richest coral reefs in the South Atlantic, where about 270 species of reef and shore fishes occur. To evaluate seasonal and ontogenetic shifts in the diet, specimens of L. analis were obtained through a fish monitoring program in four cities in southern Bahia State, from June 2005 to March 2007. Stomachs from 85 mutton snappers that ranged in size from 18.1 to 74.0 cm TL were examined. Prey were identified to the lowest possible taxon and assessed by the frequency of occurrence and volumetric methods. Variations in volume prey consumption were evaluated using non-metric multi-dimensional scaling ordination, analysis of similarity, and similarity percentage methods. Significant differences in diet composition among size classes were registered, whereas non significant differences between seasons were observed. Considering size-classes, food items consumption showed important variations: juveniles (50.1 cm TL) consumed basically fish, mostly Anguiliformes. Lutjanus analis is an important generalist reef predator, with a broad array of food resources and ontogenetic changes in the diet. This snapper species plays an important role on the trophic ecology of the Abrolhos Bank coral reefs.

Goliath grouper (Epinephelus itajara) aggregations and relative abundances were described and mapped through the use of fishermen's local ecological knowledge in Babitonga Bay in southern Brazil. Six well-experienced informants were asked to individually provide information about goliath grouper abundance and distribution, drawn over a satellite image of the study area, which was later overlaid and gathered into a final map. According to our informants, the goliath grouper occurs along a broad salinity and depth range, from shallow estuarine areas (less than 5 m deep) with high freshwater input (smaller individuals, up to 150 kg) to coastal marine-dominated environments (at least 35 m deep); (larger individuals more common, frequently reaching more than 300 kg). Fishermen referred to goliath groupers inhabiting hard substrates such as rocky reefs around islands and continental shores, submerged rocky outcrops and shipwrecks (juveniles and adults). At least two aggregation sites mapped (ranging from 2 to 60 individuals) could be concluded as spawning aggregation sites through evidence of high abundance and spawning activity. Priority research and conservation targets were identified and discussed for Babitonga Bay (e.g., design of a tagging experimental program and establishment of a marine protected area). Fishers' resource mapping provided a means of exchanging information among various disciplines while maintaining methodological rigor in a clear and straightforward way of presenting fishers' knowledge. The use of fishers' sketch maps is a promising tool for marine conservation in Brazil, with special regard to adaptive co-management regimes, where frequent environmental re-evaluations are needed.