Spatiotemporal patterns in the prevalence of microscopic hepatic changes in Gulf of Mexico Tilefish (Lopholatilus chamaeleonticeps) and associations with hepatic PAHs.

Following the 2010 Deepwater Horizon blowout, demersal longline surveys were conducted across the Gulf of Mexico (GoM) continental shelf to evaluate polycyclic aromatic hydrocarbon (PAH) exposure, tissue accumulation, and health indices in demersal fishes. Tilefish (Lopholatilus chamaeleonticeps), a target species due to Gulf-wide distribution with documented high exposure to PAHs, were collected in the north central GoM at repeat stations 2012 to 2015, and from the northwest GoM, Bay of Campeche, and Yucatán Shelf in 2015 and 2016. Liver samples (n = 239) were analyzed for microscopic hepatic changes (MHCs) by a board-certified veterinary pathologist. Histological analyzes identified 14 MHCs. Prevalence of MHCs was generally uniform throughout the GoM, except for low prevalence on the Yucatán Shelf. Inflammatory and vacuolar changes were most prevalent, while pre-neoplasia and neoplasia were rare. Tilefish sampled annually in the north central GoM showed increases in inflammatory MHCs and glycogen-type vacuolar change over time, while lipid-type vacuolar change decreased over time. Short-term exposure to PAHs was assessed by measuring PAH metabolites in bile (n = 100) using high performance liquid chromatography with fluorescence detection. Longer-term accumulation of PAHs in tissue was assessed by analyzing liver (n = 111) for PAHs and alkylated homologs using QuEChERS extractions and gas chromatography tandem mass spectrometry. Six MHCs including glycogen-type vacuolar change, biliary fibrosis, foci of cellular alteration, parasites, hepatocellular atrophy, and necrosis were significantly associated with hepatic PAH accumulation in Tilefish from the northern central GoM; however, no MHCs were associated with biliary PAH metabolites. Combined with previous studies of PAH exposure and health indices in north central GoM Tilefish post-Deepwater Horizon, which also identified decreases in hepatic lipid storage and Fulton's condition factor that were correlated to increasing PAH exposure, these data indicate concerning temporal trends and changes in hepatic energy storage.

Mercury concentrations and stable isotopes (δ15N and δ13C) in fish muscle indicate human impacts in tropical coastal lagoons.

Coastal lagoons are essential nursery habitats of many marine fishes, but they are often sites of intense human activities that impact water quality and potentially the fish using these habitats. We compared the variability in nutrient uptake (using δ15N and δ13C) and total mercury (THg) levels in juveniles and adults of three common species in two lagoons on the central Mexican coast of the Pacific Ocean during the wet and dry seasons. One of three species, Achirus mazatlanus had higher THg, δ15N, and δ13C levels in the lagoon with the greatest wastewater inputs (Barra de Navidad). Delta13C varied seasonally for all three species and THg was higher in the dry season for Lutjanus argentiventris and in males of A. mazatlanus. Our results demonstrate that mercury and stable isotopes can identify impacts of human activities on estuarine ichthyofauna and the importance of understanding seasonal and spatial variability of measures that could impact monitoring and predictions of impacts in these lagoons.

Assessment of total mercury content in tissues of Mullus argentinae in Rio de Janeiro, Brazil / Avaliação de mercúrio total em tecido comestível de Mullus argetinae coletados no Rio de Janeiro, Brasil

This study has as objective to determine total mercury (Total Hg) levels by atomic absorption spectrophotometry in 134 individuals edible part of Mullus argentinae, in two different fishing areas and two seasons in Rio de Janeiro State. Also, proximate composition was performed. Total Hg results in wet weight basis ranged from 0.0867 to 0.7476 µg.g-1 in muscle; 0.0023 to 0,1034 µg.g-1 in flippers; and 0.0177 to 0.1849 µg.g-1 in skin. Mean evaluated moisture was 73.39%; protein was 18.76%; lipid concentration of 5.36%; carbohydrates of 2.35%; and ashes were 0.85%.Results showed that Total Hg contents was lower than accepted limits established by regulatory organization. Higher averages were observed in muscle (0.2441 µg.g-1) when compared with skin (0.2386 µg.g-1) and flippers (0.0195 µg.g-1). In general, samples collected on summer showed higher values of total Hg when comparing to winter. Regarding beach areas there was no significant difference (p>0.05). We can conclude that this specie should be cautious consumed because of total Hg bioaccumulation characteristics, although neither levels were above limits established.

O objetivo deste estudo foi determinar o teor de mercúrio no tecido comestível de Mullus argentinae, conhecido como peixe trilha, espécie amplamente consumida no Rio de Janeiro, Brasil. Foi determinado o teor de mercúrio total (Hg total) por espectrofotometria de absorção atômica em 134 amostras, coletados em duas áreas e estações climáticas diferentes. Além disso, foi avaliada a composição centesimal das amostras. Os resultados de Hg total em peso úmido variaram de 0,0867 a 0,7476 µg.g-1 no músculo; 0,0023 a 0,1034 µg.g-1 nas nadadeiras; e 0,0177 a 0,1849 µg.g-1 na pele. Os valores médios da composição centesimal foram de 73,30% de umidade, 18,76% de proteína, 5,36% de lipídios, 2,35% de carboidratos e 0,85% de matéria mineral. Os resultados das 134 amostras analisadas demostraram que os teores de Hg Total apresentam concentração inferior aos limites aceitos pelos órgãos reguladores. As maiores médias foram observadas no músculo (0,2441 µg.g-1) quando comparadas à pele (0,2386 µg.g-1) e nadadeiras (0,0195 µg.g-1). Em geral, as amostras coletadas no verão apresentaram maiores valores de Hg total em relação ao inverno. Em relação aos locais de coleta não houve diferença significativa (p> 0,05). Podemos concluir que esta espécie deve ser consumida com cautela devido às características de bioacumulação do Hg total, apesar das médias apresentadas estarem abaixo dos limites estabelecidos pela legislação.

Spatial contrasts in hepatic and biliary PAHs in Tilefish (Lopholatilus chamaeleonticeps) throughout the Gulf of Mexico, with comparison to the Northwest Atlantic.

A multinational demersal longline survey was conducted on the Gulf of Mexico continental shelf over the years 2015 and 2016 to generate a Gulf-wide baseline of polycyclic aromatic hydrocarbon (PAH) concentrations in demersal fishes. Tilefish (Lopholatilus chamaeleonticeps) were sampled in all regions of the Gulf of Mexico for biometrics, bile, and liver. Tilefish liver was also obtained from surveys in the northwest Atlantic Ocean for comparison. Liver tissues (n = 305) were analyzed for PAHs and select alkylated homologs using QuEChERS extractions and gas chromatography tandem mass spectrometry. Bile samples (n = 225) were analyzed for biliary PAH metabolites using high-performance liquid chromatography with fluorescence detection. Spatial comparisons indicate the highest levels of PAH exposure and hepatic accumulation in the north central Gulf of Mexico, with decreasing concentrations moving from the north central Gulf counterclockwise, and an increase on the Yucatán Shelf. Hepatic PAH concentrations were similar between the Gulf of Mexico and the northwest Atlantic, however, Tilefish from the northwest Atlantic had higher concentrations and more frequent detection of carcinogenic high molecular weight PAHs. Overall, results demonstrate that PAH pollution was ubiquitous within the study regions, with recent exposure and hepatic accumulation observed in Tilefish from both the Gulf of Mexico and northwest Atlantic.

Patrones de distribución espacial de la riqueza de peces de fondos blandos en la plataforma y talud continentales del Caribe Colombiano / Spatial richness patterns of soft-bottom fish in the colombian caribbean continental shelf and slope

ABSTRACT This study presents a spatial analysis of species richness of soft-bottom bony and cartilaginous fish species in the Colombian Caribbean. The dataset consisted of 625 species distributed among 15651 georeferenced occurrences. The global richness completeness analysis suggests that the list is close to completion but that probably more species await being registered at greater depths. In spatial terms, our knowledge of fish richness remains incomplete as none of the spatial units, in which the general area was divided reached 100 % completeness and few reached 70 % or higher completeness probably due to the incidence of numerous rare species. The Guajira, Palomino, Tayrona and Golfo de Salamanca zones, displayed the highest observed and predicted richness. The Galerazamba, Arco (coralline archipelago) and Arboletes zones were predicted to have high species richness. In view of the results, marine protected areas need to be expanded to include soft-bottom habitats. Future research efforts should focus on the high species richness areas observed and predicted and surveys should include more extensively depth locations.

RESUMEN Este estudio presenta un análisis espacial de la riqueza de especies de peces óseos y cartilaginosos de fondos blandos del Caribe Colombiano. El conjunto de datos consiste de 625 especies distribuidas en 15651 registros georeferenciados. El análisis de completitud global de riqueza sugiere que la lista está próxima a estar completa pero que probablemente mas especies están pendientes de ser registradas a mayores profundidades. En términos espaciales el conocimiento de la riqueza de especies se mantiene incompleto ya que ninguna de las unidades espaciales en que el área general fue dividida, alcanzo el 100 % de completitud y pocas alcanzaron el 70 % o mas, probablemente debido a la influencia de muchas especies raras. Las zonas Guajira, Palomino, Tayrona y el Golfo de Salamanca mostraron la mayor riqueza observada y esperada. Para las zonas Galerazamba, Arco (archipiélago coralino) y Arboletes se predice alta riqueza de especies. En vista de los resultados, las áreas marinas protegidas deben expandirse para incluir hábitats de fondos blandos. Esfuerzos futuros de investigación deben enfocarse en las áreas de alta riqueza de especies tanto observada como esperada e incluir más extensamente localidades profundas.

Spatial and temporal distribution patterns of the silver mojarra Eucinostomus argenteus (Perciformes: Gerreidae) in a tropical semi-enclosed bay.

This study determined the spatial and temporal distributions of the silver mojarra Eucinostomus argenteus (Perciformes: Gerreidae), one of the most abundant teleost species in bays and estuaries. Sampling was conducted from July 2005 to June 2007. The species was captured on all sampling dates and at six of the seven sampling stations. Approximately 80% of the individuals were below the size of first sexual maturity (12·0 cm total length, LT ). Although the spatial distribution of juveniles and adults differed throughout the study period, the environmental variables measured explained only a small part of their distribution. The recruitment period occurred during the first part of each year. Despite the high pollution levels in Guanabara Bay, this coastal system plays an important role as a nursery ground and for the growth of E. argenteus.

Distribuição espaço-temporal de Micropogonias furnieri (Perciformes, Sciaenidae) em um estuário tropical no sudeste do Brasil / Time-space distribution of Micropogonias furnieri (Perciformes, Sciaenidae) in a tropical estuary in Southeastern Brazil

The whitemouth croaker, Micropogonias furnieri, is a commercially very important marine fish along its occurrence area that uses estuaries early in its life. In order to describe the time-space distribution of M. furnieri in Guanabara Bay, southeastern Brazil, bottom otter trawlings were carried out every fifteen days between July 2005 and June 2007. The monthly variation of the relative abundance of M. furnieri was checked from catch per unit of effort (CPUE), and the size structure of the caught species, in time and space, was analyzed from histograms with length (TL) classes with an interval of 0.5 cm. The Kruskal-Wallis test was employed to test the hypothesis that sampling points were occupied by groups of equal mean of TL. The whitemouth croaker was present in all sampling sites throughout the year and juveniles were the most abundant population stratum. Statistically significant differences (p < 0,05) in length classes between different sampling sites were found. While smaller individuals had a higher frequency in the upper and middle estuary, and some sampling sites at the lower estuary, larger individuals were mainly found in the lower estuary. Recruitment peaks occurred in late Fall, Winter and Spring, indicating a long period of reproduction. Guanabara Bay has an important role as marine nursery and growth area for M. furnieri, with the physiography of the estuary being one of the most relevant factors in the space distribution of the species.

A corvina, Micropogonias furnieri, é um recurso pesqueiro importante ao longo de sua área de ocorrência e utiliza os estuários em seus primeiros estágios de vida. Com o objetivo de descrever a distribuição espaço-temporal da espécie no estuário da Baía de Guanabara, sudeste do Brasil, foram realizados arrastos de fundo quinzenais entre julho de 2005 e junho de 2007. A variação mensal da abundância relativa de M. furnieri foi verificada pela captura por unidade de esforço (CPUE), e a estrutura do tamanho de captura da espécie, no tempo e no espaço, foi analisada a partir de histogramas com classes de comprimento (CT) com intervalo de 0,5 cm. O teste de Kruskal-Wallis foi empregado para testar a hipótese de que os pontos de coleta eram ocupados por grupos com média de CT iguais. A corvina esteve presente em todos os pontos de coleta ao longo do ano, sendo os juvenis o estrato populacional capturado em maior abundância. Diferenças estatisticamente significativas (p < 0,05) foram observadas para a estrutura de classes de tamanho entre os diferentes pontos. Os menores indivíduos ocuparam o alto e o médio estuário, além de determinados locais do baixo estuário; os maiores exemplares foram encontrados principalmente no baixo estuário. Picos de recrutamento ocorreram no final do Outono, no Inverno e na Primavera, indicando um período longo de reprodução. A Baía de Guanabara tem papel importante como berçário e área de crescimento para M. furnieri, sugerindo que a fisiografia do estuário seja um dos fatores mais relevantes na distribuição espacial da espécie.

Distribuição espaço-temporal de Micropogonias furnieri (Perciformes, Sciaenidae) em um estuário tropical no sudeste do Brasil / Time-space distribution of Micropogonias furnieri (Perciformes, Sciaenidae) in a tropical estuary in Southeastern Brazil

The whitemouth croaker, Micropogonias furnieri, is a commercially very important marine fish along its occurrence area that uses estuaries early in its life. In order to describe the time-space distribution of M. furnieri in Guanabara Bay, southeastern Brazil, bottom otter trawlings were carried out every fifteen days between July 2005 and June 2007. The monthly variation of the relative abundance of M. furnieri was checked from catch per unit of effort (CPUE), and the size structure of the caught species, in time and space, was analyzed from histograms with length (TL) classes with an interval of 0.5 cm. The Kruskal-Wallis test was employed to test the hypothesis that sampling points were occupied by groups of equal mean of TL. The whitemouth croaker was present in all sampling sites throughout the year and juveniles were the most abundant population stratum. Statistically significant differences (p < 0,05) in length classes between different sampling sites were found. While smaller individuals had a higher frequency in the upper and middle estuary, and some sampling sites at the lower estuary, larger individuals were mainly found in the lower estuary. Recruitment peaks occurred in late Fall, Winter and Spring, indicating a long period of reproduction. Guanabara Bay has an important role as marine nursery and growth area for M. furnieri, with the physiography of the estuary being one of the most relevant factors in the space distribution of the species.(AU)

A corvina, Micropogonias furnieri, é um recurso pesqueiro importante ao longo de sua área de ocorrência e utiliza os estuários em seus primeiros estágios de vida. Com o objetivo de descrever a distribuição espaço-temporal da espécie no estuário da Baía de Guanabara, sudeste do Brasil, foram realizados arrastos de fundo quinzenais entre julho de 2005 e junho de 2007. A variação mensal da abundância relativa de M. furnieri foi verificada pela captura por unidade de esforço (CPUE), e a estrutura do tamanho de captura da espécie, no tempo e no espaço, foi analisada a partir de histogramas com classes de comprimento (CT) com intervalo de 0,5 cm. O teste de Kruskal-Wallis foi empregado para testar a hipótese de que os pontos de coleta eram ocupados por grupos com média de CT iguais. A corvina esteve presente em todos os pontos de coleta ao longo do ano, sendo os juvenis o estrato populacional capturado em maior abundância. Diferenças estatisticamente significativas (p < 0,05) foram observadas para a estrutura de classes de tamanho entre os diferentes pontos. Os menores indivíduos ocuparam o alto e o médio estuário, além de determinados locais do baixo estuário; os maiores exemplares foram encontrados principalmente no baixo estuário. Picos de recrutamento ocorreram no final do Outono, no Inverno e na Primavera, indicando um período longo de reprodução. A Baía de Guanabara tem papel importante como berçário e área de crescimento para M. furnieri, sugerindo que a fisiografia do estuário seja um dos fatores mais relevantes na distribuição espacial da espécie.(AU)

Sustainability of capture of fish bycatch in the prawn trawling in northeastern Brazil

The prawn fishery produces more discards than any other type of catch and captures a large quantity of immature individuals. This research aimed to assess the sustainability of capture of fish bycatch in prawn trawling. Each species was assessed according to two groups of criteria: (1) their relative vulnerability to capture by trawl and mortality due to this fishery (2) recovery capacity of the specie after a possible collapse of the population. Within each group, each species was ranked (1-3), being 1 the highest value, meaning the species is highly susceptible to capture or has a low resilience. A total of 8,894 individuals were caught, belonging to 28 families. The species with capture least sustainable were Stellifer rastrifer and Isopisthus parvipinnis. These latter species are highly susceptible since they are either benthic or demersal, and their diet may include benthic organism. Chirocentrodon bleekerianus and Anchoa tricolor were the most likely fishes to be sustainable since they are pelagic, they are least susceptible to capture by trawls, and also have a greater capacity to recover, as most individuals have bred before capture. Due to the fishery's multi-specific nature, it is difficult to implement mitigation measures for specific species. Thus, the creation of fishing exclusion zones should be considered as the most appropriate management measure.(AU)

A pesca de arrasto de camarão produz mais descarte do que qualquer outra pescaria e captura uma grande quantidade de indivíduos imaturos. Esta pesquisa visa determinar a sustentabilidade da captura da ictiofauna acompanhante na pesca de arrasto de camarão. Cada espécie foi analisada de acordo com dois grupos de critérios: (1) vulnerabilidade à captura pela rede de arrasto e mortalidade ocasionada por esta pescaria; e (2) capacidade de recuperação da população para minimizar. Dentro de cada critério as espécies foram classificadas de 1 a 3, sendo 1 o valor mais alto, indicando que a espécie é altamente susceptível à captura ou tem baixa capacidade de recuperação. Um total de 8.894 indivíduos foram capturados, pertencendo a 28 famílias. As espécies com captura menos sustentável foram Stellifer rastrifer e Isopisthus parvipinnis. Estas espécies são altamente susceptíveis, pois são bentônicas ou demersais e suas dietas incluem organismos bentônicos. Chirocentrodon bleekerianus e Anchoa tricolor foram as espécies que apresentaram a captura mais sustentável. Por serem pelágicas, são menos susceptíveis à captura por arrastos de fundo, além disto, apresentaram uma grande capacidade de recuperação, pois a maior parte dos indivíduos capturados encontrava-se acima do seu tamanho de primeira maturação sexual. Devido à natureza multiespecífica da pescaria é difícil implementar medidas mitigatórias específicas. Assim, a criação de zona de exclusão de pesca deve ser considerada como a medida de manejo mais adequada.(AU)

Ictiofauna acompanhante na pesca artesanal do camarão sete-barbas (Xiphopenaeus kroyeri) no litoral sul do Brasil / Ichthyofauna bycatch of sea-bob shrimp (Xiphopenaeus kroyeri) fishing in the town of Porto Belo, SC, Brazil

A pesca artesanal dirigida ao camarão sete-barbas (Xiphopenaeus kroyeri), usando o método de arrasto motorizado com portas, tem sido praticada na costa de Santa Catarina, onde ele gera emprego e renda, e ajuda a manter a tradição cultural tradicional açoriana viva, desde 1960. Com o objectivo de analisar a qualidade e a quantidade das capturas acidentais da ictiofauna, efetuou-se sazonalmente, dois arrastos por isóbata (10-20‑30 m) entre novembro/2009 e agosto/2010, duração de 20 min/cada, velocidade média dois nós e, registrados temperaturas e salinidades da água de fundo. As capturas totalizaram 10868 peixe (208.34 kg), distribuídos em 31 famílias e 62 espécies, com uma proporção de peixe/camarão de 5,19/1 kg. A família mais abundante foi Sciaenidae (86.13%), seguido por Batrachoididae (2.70%) e Trichiuridae (2,44%). Os índices de diversidade e equabilidade apresentaram padrões similares de variação, os maiores valores ocorreram na Primavera na profundidade de 30 m e a mais baixa no inverno, a 20 m. A análise de Cluster formou quatro agrupamentos, sendo um deles, pequeno e dominante de Sciaenidae Stellifer brasiliensis, S. rastrifer, Paralonchurus brasiliensis, Isopisthus parvipinnis e Larimus breviceps. Os exemplares jovens dessas espécies e de outras, com pouco ou sem valor comercial, camarões miúdos e demais macro-invertebrados acompanhantes capturados são descartados ao mar, geralmente mortos. Além do impacto nas cadeias tróficas, essa prática contínua, pode agravar ainda mais a situação do pescador artesanal com o declínio desses recursos nas capturas futuras.

The activity of artisanal fishing for the sea-bob shrimp, using the method of motorized dragnet with rings, has been practised on the Santa Catarina coast, where it generates jobs and income, and helps keep the traditional Azorean cultural tradition alive, since 1960. With the aim of analyzing the quality and quantity of the ichthyofauna bycatch, two trawls were carried out per isobath (10-20-30 m), seasonally, between November 2009 and August 2010 (i.e. summer, spring and winter), for 20 minutes each, at an average speed of two knots, and the bottom water temperatures and salinities recorded. The captures totalled 10868 fish (208.34 kg), distributed among 31 families and 62 species, with a fish/shrimp ratio of 5.19/1 kg. The most abundant family was Sciaenidae (86.13%), followed by Batrachoididae (2.70%) and Trichiuridae (2.44%). The diversity and evenness indices presented similar patterns of variation, the highest values occurring in spring at 30 m and the lowest in winter at 20 m. Cluster analysis led to the creation of four groups; one of them small and dominated by the Sciaenidae Stellifer brasiliensis, S. rastrifer, Paralonchurus brasiliensis, Isopisthus parvipinnis and Larimus breviceps. The young of this and other species, which are of little or no commercial value, along with tiny shrimps and other macroinvertebrates that enter the dragnets, are thrown back into the sea, usually dead. Besides the negative impact on the food chain, this continued practice could exacerbate the situation of artisanal fishermen even further, with the gradual, future decline of these resources.

Sustainability of capture of fish bycatch in the prawn trawling in northeastern Brazil

The prawn fishery produces more discards than any other type of catch and captures a large quantity of immature individuals. This research aimed to assess the sustainability of capture of fish bycatch in prawn trawling. Each species was assessed according to two groups of criteria: (1) their relative vulnerability to capture by trawl and mortality due to this fishery (2) recovery capacity of the specie after a possible collapse of the population. Within each group, each species was ranked (1-3), being 1 the highest value, meaning the species is highly susceptible to capture or has a low resilience. A total of 8,894 individuals were caught, belonging to 28 families. The species with capture least sustainable were Stellifer rastrifer and Isopisthus parvipinnis. These latter species are highly susceptible since they are either benthic or demersal, and their diet may include benthic organism. Chirocentrodon bleekerianus and Anchoa tricolor were the most likely fishes to be sustainable since they are pelagic, they are least susceptible to capture by trawls, and also have a greater capacity to recover, as most individuals have bred before capture. Due to the fishery's multi-specific nature, it is difficult to implement mitigation measures for specific species. Thus, the creation of fishing exclusion zones should be considered as the most appropriate management measure.

A pesca de arrasto de camarão produz mais descarte do que qualquer outra pescaria e captura uma grande quantidade de indivíduos imaturos. Esta pesquisa visa determinar a sustentabilidade da captura da ictiofauna acompanhante na pesca de arrasto de camarão. Cada espécie foi analisada de acordo com dois grupos de critérios: (1) vulnerabilidade à captura pela rede de arrasto e mortalidade ocasionada por esta pescaria; e (2) capacidade de recuperação da população para minimizar. Dentro de cada critério as espécies foram classificadas de 1 a 3, sendo 1 o valor mais alto, indicando que a espécie é altamente susceptível à captura ou tem baixa capacidade de recuperação. Um total de 8.894 indivíduos foram capturados, pertencendo a 28 famílias. As espécies com captura menos sustentável foram Stellifer rastrifer e Isopisthus parvipinnis. Estas espécies são altamente susceptíveis, pois são bentônicas ou demersais e suas dietas incluem organismos bentônicos. Chirocentrodon bleekerianus e Anchoa tricolor foram as espécies que apresentaram a captura mais sustentável. Por serem pelágicas, são menos susceptíveis à captura por arrastos de fundo, além disto, apresentaram uma grande capacidade de recuperação, pois a maior parte dos indivíduos capturados encontrava-se acima do seu tamanho de primeira maturação sexual. Devido à natureza multiespecífica da pescaria é difícil implementar medidas mitigatórias específicas. Assim, a criação de zona de exclusão de pesca deve ser considerada como a medida de manejo mais adequada.

Spatiotemporal variations of the ichthyofaunal structure accompanying the seabob shrimp, Xiphopenaeus kroyeri (Crustacea: Penaeidae), fishery in important fishery areas of the Santa Catarina shore, Brazil

The present study analyzed qualitatively and quantitatively the temporal and spatial changes in the fish assemblages present in seabob shrimp distribution sites in two important fishing areas of the Santa Catarina coast. Monthly bottom trawls, conducted between March 2007 and February 2008 in Balneário Barra do Sul and Penha, yielded a total of 38,608 specimens belonging to 54 species, of which 35 occurred in both regions. The Sciaenidae was the most represented family in both number of species and abundance of individuals. The dominant species were Stellifer rastrifer (Jordan, 1889), S. brasiliensis (Schultz, 1945), Paralonchurus brasiliensis (Steindachner, 1875), Isopisthus parvipinnis (Cuvier, 1830), Trichiurus lepturus (Linnaeus, 1758), and Pellona harroweri (Fowler, 1917). The ichthyofaunal structure showed a spatiotemporal dependence with significant differences in March 2007 and January and February 2008 between Balneário Barra do Sul and Penha. The main differences were attributed to dominant species, which were responsible for significantly altering the abundance of the assemblages. The species richness was similar in both sites, whereas the diversity and equitability indices showed monthly fluctuation patterns that differed between Balneário Barra do Sul and Penha. The Shannon index differed in August, September and November 2007 and January and February 2008, with an H' ranging from 0.74 to 1.98 influenced by dominant species, whereas significant variations were observed for the Pielou index in November 2007 and February 2008. The Berger-Parker index demonstrated a clear dominance pattern where the monthly numeric contribution of a single species ranged from approximately 30 to 80%. Although the results showed differences between fishing grounds 25% of the time, we conclude that fish assemblies captured as accompanying fauna in artisanal seabob shrimp fisheries showed statistically similar characteristics for most of the year, although Balneário Barra do Sul and Penha are 35 km away from each other.

Spatiotemporal variations of the ichthyofaunal structure accompanying the seabob shrimp, Xiphopenaeus kroyeri (Crustacea: Penaeidae), fishery in important fishery areas of the Santa Catarina shore, Brazil

The present study analyzed qualitatively and quantitatively the temporal and spatial changes in the fish assemblages present in seabob shrimp distribution sites in two important fishing areas of the Santa Catarina coast. Monthly bottom trawls, conducted between March 2007 and February 2008 in Balneário Barra do Sul and Penha, yielded a total of 38,608 specimens belonging to 54 species, of which 35 occurred in both regions. The Sciaenidae was the most represented family in both number of species and abundance of individuals. The dominant species were Stellifer rastrifer (Jordan, 1889), S. brasiliensis (Schultz, 1945), Paralonchurus brasiliensis (Steindachner, 1875), Isopisthus parvipinnis (Cuvier, 1830), Trichiurus lepturus (Linnaeus, 1758), and Pellona harroweri (Fowler, 1917). The ichthyofaunal structure showed a spatiotemporal dependence with significant differences in March 2007 and January and February 2008 between Balneário Barra do Sul and Penha. The main differences were attributed to dominant species, which were responsible for significantly altering the abundance of the assemblages. The species richness was similar in both sites, whereas the diversity and equitability indices showed monthly fluctuation patterns that differed between Balneário Barra do Sul and Penha. The Shannon index differed in August, September and November 2007 and January and February 2008, with an H' ranging from 0.74 to 1.98 influenced by dominant species, whereas significant variations were observed for the Pielou index in November 2007 and February 2008. The Berger-Parker index demonstrated a clear dominance pattern where the monthly numeric contribution of a single species ranged from approximately 30 to 80%. Although the results showed differences between fishing grounds 25% of the time, we conclude that fish assemblies captured as accompanying fauna in artisanal seabob shrimp fisheries showed statistically similar characteristics for most of the year, although Balneário Barra do Sul and Penha are 35 km away from each other.

Spatiotemporal variations of the ichthyofaunal structure accompanying the seabob shrimp, Xiphopenaeus kroyeri (Crustacea: Penaeidae), fishery in important fishery areas of the Santa Catarina shore, Brazil

The present study analyzed qualitatively and quantitatively the temporal and spatial changes in the fish assemblages present in seabob shrimp distribution sites in two important fishing areas of the Santa Catarina coast. Monthly bottom trawls, conducted between March 2007 and February 2008 in Balneário Barra do Sul and Penha, yielded a total of 38,608 specimens belonging to 54 species, of which 35 occurred in both regions. The Sciaenidae was the most represented family in both number of species and abundance of individuals. The dominant species were Stellifer rastrifer (Jordan, 1889), S. brasiliensis (Schultz, 1945), Paralonchurus brasiliensis (Steindachner, 1875), Isopisthus parvipinnis (Cuvier, 1830), Trichiurus lepturus (Linnaeus, 1758), and Pellona harroweri (Fowler, 1917). The ichthyofaunal structure showed a spatiotemporal dependence with significant differences in March 2007 and January and February 2008 between Balneário Barra do Sul and Penha. The main differences were attributed to dominant species, which were responsible for significantly altering the abundance of the assemblages. The species richness was similar in both sites, whereas the diversity and equitability indices showed monthly fluctuation patterns that differed between Balneário Barra do Sul and Penha. The Shannon index differed in August, September and November 2007 and January and February 2008, with an H' ranging from 0.74 to 1.98 influenced by dominant species, whereas significant variations were observed for the Pielou index in November 2007 and February 2008. The Berger-Parker index demonstrated a clear dominance pattern where the monthly numeric contribution of a single species ranged from approximately 30 to 80%. Although the results showed differences between fishing grounds 25% of the time, we conclude that fish assemblies captured as accompanying fauna in artisanal seabob shrimp fisheries showed statistically similar characteristics for most of the year, although Balneário Barra do Sul and Penha are 35 km away from each other.

Mudanças temporais na abundância e diversidade da fauna de peixes do infralitoral raso de uma praia, sul do Brasil

Abundance and diversity of the fish fauna in the shallow infralittoral region of Atami Beach, Paraná, Brazil, were studied through monthly collections between July 1998 and June 1999. A total of 7553 fishes from 70 species and 26 families, mainly juvenile forms, was captured in the area. The mean captures in number of species, number of fish and biomass were larger from the end of spring to the middle of autumn; seasonal tendency in richness, diversity (number) and equitability indices were not observed. The largest mean dissimilarity in the composition of the ichthyofauna occurred between June and May in comparison to the period between July and October. The species that contributed most to this dissimilarity were Selene setapinnis (Mitchill, 1815), Conodon nobilis (Linnaeus, 1758) and Stellifer rastrifer (Jordan, 1889). Three great groups reflecting patterns of temporal occurrence of the most abundant species were identified.

Mudanças temporais na abundância e diversidade da fauna de peixes do infralitoral raso de uma praia, sul do Brasil

Abundance and diversity of the fish fauna in the shallow infralittoral region of Atami Beach, Paraná, Brazil, were studied through monthly collections between July 1998 and June 1999. A total of 7553 fishes from 70 species and 26 families, mainly juvenile forms, was captured in the area. The mean captures in number of species, number of fish and biomass were larger from the end of spring to the middle of autumn; seasonal tendency in richness, diversity (number) and equitability indices were not observed. The largest mean dissimilarity in the composition of the ichthyofauna occurred between June and May in comparison to the period between July and October. The species that contributed most to this dissimilarity were Selene setapinnis (Mitchill, 1815), Conodon nobilis (Linnaeus, 1758) and Stellifer rastrifer (Jordan, 1889). Three great groups reflecting patterns of temporal occurrence of the most abundant species were identified.

Mudanças temporais na abundância e diversidade da fauna de peixes do infralitoral raso de uma praia, sul do Brasil

Abundance and diversity of the fish fauna in the shallow infralittoral region of Atami Beach, Paraná, Brazil, were studied through monthly collections between July 1998 and June 1999. A total of 7553 fishes from 70 species and 26 families, mainly juvenile forms, was captured in the area. The mean captures in number of species, number of fish and biomass were larger from the end of spring to the middle of autumn; seasonal tendency in richness, diversity (number) and equitability indices were not observed. The largest mean dissimilarity in the composition of the ichthyofauna occurred between June and May in comparison to the period between July and October. The species that contributed most to this dissimilarity were Selene setapinnis (Mitchill, 1815), Conodon nobilis (Linnaeus, 1758) and Stellifer rastrifer (Jordan, 1889). Three great groups reflecting patterns of temporal occurrence of the most abundant species were identified.