
Marcelo Vianna
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Aug 1994 - Aug 2002
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Research Items (84)
- Nov 2018
An important step in fishery management is to classify fishing vessels by their technical, power, range and impact capacities. This allows management improvement for environmental, social and economic purposes. Technical features are commonly used to classify vessels, but are inadequately addressed for small-scale fisheries (SSF), especially in estuaries. This study analyzed 685 small fishing vessels in order to determine the best way to classify them and suggest how this can improve estuarine SSF management. Technical features, target species, and the degree of urbanization and income of the community were considered. Estuarine-dependent vessels differ from coastal vessels. Their simpler technology increases overlaps of target species and fishing gear. Technical features commonly used to classify vessels (length, engine power and tonnage) are inappropriate for those with low technology. Instead, the degree of technical homogeneity, the number of fishing gears, and the overlap of target species should be considered. We suggest the classification of vessels in management units for estuarine small-scale vessels: a group of vessels operating in the same area, with very low technology, similar fishing range and fishing capacity, a multi-gear pattern, and high target species overlap. Vessels with different main fishing gear may represent the same management unit, because the simple technology required by each gear allows the same vessel to uses several types. The multi-gear and multi-species strategy impairs the use of traditional gear-based management, yet enables low-income fishermen to continue fishing. Vessels with lower technology were observed in less-urbanized communities and had lower income, and therefore these fishermen depend more on the estuarine fishery. Financial capacity stimulates technology and increases fishing capacity, range and gear specialization. Simple technology may help to improve food security and alleviate poverty by maximizing catch diversity. This study identified management units through a novel use of the features of small-scale vessels. We discuss important issues that influence the technological development of small-scale vessels and how this method may improve SSF management.
- Aug 2018
Determination of the growth parameters of a species is an indispensable requirement for understanding its biology and consequently the management of its fishery. In fisheries science, calculations of longevity, mortality rates and stock-assessment models depend on the availability of growth data. Genidens genidens, one of the most common ariid species in Brazil, is a potential sentinel species for biomonitoring in Guanabara Bay, one of the country’s most degraded estuarine ecosystems. The present study investigated the growth parameters of G. genidens, providing supporting information for its management. Individuals were measured, sexed, and the number of rings in the lapillus otolith counted. The periodicity in the formation of the rings was determined by the monthly ratio of the edge type. Individuals from 0 to 11.5 years old were captured, including some that were older than previously reported. Our results showed that this species forms two growth rings per year, one in summer and the other in winter; the summer ring is formed one month later in males than in females, due to the period of oropharyngeal incubation of the offspring. Sexual dimorphism was also observed in the growth rate: males grow faster, and consequently reach smaller sizes than females. We can conclude that the parental care carried out by males and the high energy expenditure in forming the large oocytes by females mark the otoliths and reveal life-cycle particularities differently in each sex.
- Maria Dornelas
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- Laura Antao
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- Faye Moyes
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- Thomas Hickler
![[object Object]](https://c5.rgstatic.net/m/4671872220764/images/template/default/profile/profile_default_m.jpg)
- Maria Dornelas
![[object Object]](https://i1.rgstatic.net/ii/profile.image/345633237028866-1459416793930_Q64/Maria_Dornelas.jpg)
- Laura Antao
![[object Object]](https://i1.rgstatic.net/ii/profile.image/692568144752660-1542132521658_Q64/Laura_Antao.jpg)
- Faye Moyes
![[object Object]](https://i1.rgstatic.net/ii/profile.image/279003207356418-1443530956049_Q64/Faye_Moyes.jpg)
- [...]
- Thomas Hickler
![[object Object]](https://c5.rgstatic.net/m/4671872220764/images/template/default/profile/profile_default_m.jpg)
- Maria Dornelas
![[object Object]](https://i1.rgstatic.net/ii/profile.image/345633237028866-1459416793930_Q64/Maria_Dornelas.jpg)
- Laura Antao
![[object Object]](https://i1.rgstatic.net/ii/profile.image/692568144752660-1542132521658_Q64/Laura_Antao.jpg)
- Faye Moyes
![[object Object]](https://i1.rgstatic.net/ii/profile.image/279003207356418-1443530956049_Q64/Faye_Moyes.jpg)
- [...]
- Thomas Hickler
![[object Object]](https://c5.rgstatic.net/m/4671872220764/images/template/default/profile/profile_default_m.jpg)
- Maria Dornelas
![[object Object]](https://c5.rgstatic.net/m/4671872220764/images/template/default/profile/profile_default_m.jpg)
- Laura Antao
![[object Object]](https://i1.rgstatic.net/ii/profile.image/692568144752660-1542132521658_Q64/Laura_Antao.jpg)
- Faye Moyes
![[object Object]](https://i1.rgstatic.net/ii/profile.image/279003207356418-1443530956049_Q64/Faye_Moyes.jpg)
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- Michael L. Zettler
![[object Object]](https://c5.rgstatic.net/m/4671872220764/images/template/default/profile/profile_default_m.jpg)
Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene.
Main types of variables included: The database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.Spatial location and grain: BioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1,000,000,000,000 cm2).
Time period and grain: BioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year. Major taxa and level of measurement: BioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates.
Software format: .csv and .SQL.
Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the anthropocene.
Main types of variables included: The database contains 8 773 553 species abundance records, from assemblages consistently sampled for a minimum of two, not necessarily consecutive, years. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.
Spatial location and grain: BioTIME is a global database of 547 161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1 000 000 000 000 cm2).
Time period and grain: BioTIME records span from 1874 to 2016. The minimum temporal grain across all datasets in BioTIME is year.
Major taxa and level of measurement: BioTIME includes data from 44 360 species across the plant an animal kingdoms, ranging from plants, plankton, and terrestrial invertebrates to small and large vertebrates.
Software format: .csv and .SQL
Project - Estrutura e Funções do ecossistema da Baia de Guanabara: uma Pesquisa Ecológica de Longa Duração
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- May 2018
- Estrutura e Funções do ecossistema da Baia de...
Update
Rebeca Almeida Marques
Orientadores: Marcelo Vianna e Co-orientador: Antônio Mateo Solé Cava
Abstract da Dissertação de Mestrado submetida ao Programa de Pós-graduação em Biodiversidade e Biologia Evolutiva, Instituto de Biologia, da Universidade Federal do Rio de Janeiro, como parte dos requisitos necessários à obtenção do título de Mestre em Biodiversidade e Biologia Evolutiva.
Usually, statistical fisheries data are obtained at landing, through a rapid classification of fish and their categorization under the trade names given to species. However, analyses of the morphology and species classification are complicated, especially in elasmobranchs, after fin and head are removed, which contributes to labeling errors and allows frauds during marketing. In this context, the objective of this dissertation was to identify the species composition of elasmobranchs landed in Rio de Janeiro, providing identification strategies to support a plan for more efficient labelling and management. Samples were obtained from the landings of the artisanal fleet and fish markets in the State of Rio de Janeiro, between November 2012 and May 2014. At the time of collection, information was recorded about the rays landed, fishing method, place of origin and common name, and later a ethnobiology interview was performed with the fishermen of the region to obtain empirical knowledge about the species collected. For taxonomic identification of whole or processed animals, morphological, metric and molecular techniques were employed. 279 individuals belonging to ten species Atlantoraja castelnaui, Dasyatis americana, Dasyatis gutatta, Dasyatis hypostigma, Gymnura altavela, Myliobatis freminvillii, Rhinoptera bonasus, Rhinoptera brasiliensis, Rioraja agassizi e Sympterygia acuta in seven genera of Batoidea were analyzed. The fishing method most commonly used to collect specimens was the gill net. The common name used by fishermen was more related with the location where they lived than with the form of fishing employed. Morphometric analyses resulted in a biometric summary for each species; as well as conversion equations of length and weight of pectoral fin to whole individuals for each species and different gender; and 10 variables significantly determining as diagnostic characters for distinguishing genera of batoidea. The genetic identification was used as a way of verifying the morphological identification. As a monitoring strategy for estimating the biomass of specific rays landed by artisanal fisheries in the state of Rio de Janeiro was developed a dichotomous key to identify specific coastal rays by the pectoral fin which together with morphometric relationships and conversions equations presented in the dissertation are an excellent tool for monitoring and conservation of the species involved, avoiding erroneous and incomplete diagnosis.
Keywords: Elasmobranchs; morphometry; Dichotomous key; Pectoral fin; Rio de Janeiro.
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This contribution presents a brief morphometric description of adult females and
embryos of the ray Gymnura altavela. Two females, pregnant with a total of five em‐
bryos, were captured in Rio de Janeiro, southeastern Brazil, and their morphometry
was compared to their respective embryos. The embryos showed higher body pro‐
portions (%DW) than adults, regardless of sex, which may be an effect of ontogeny
- Apr 2018
Flounders of the genus Paralichthys are important resources for artisanal and industrial fisheries and for aquaculture. Scientometric analysis of the literature on 11 Western Atlantic species of Paralichthys available in two scientific databases, ISI Web of Science and SciELO, was conducted, concentrating on documents relating to fisheries science. The 414 articles identified focused predominantly on two species found only in Canada and the United States, Paralichthys dentatus (46.1% of the studies) and Paralichthys lethostigma (32.1%). The third most commonly studied species was Paralichthys orbignyanus (11.7%), found only off Brazil, Uruguay, and Argentina. Fisheries science studies comprised 20% of the total (81 articles) and were completed mainly in the United States (84%), followed by Argentina (8.6%) and Brazil (two articles; 2.5%). The number of articles on aquaculture of Paralichthys surpassed all other areas of study and focused on the species of greatest economic interest. The literature revealed that aquaculture is the primary motive for research on this genus, especially in the last three decades, with a view toward commercial fish farming or repopulating the stocks of P. dentatus, P. lethostigma, and P. orbignyanus rather than an interest in extractive fishing of these species.
Project - QUALIPESCA GUANABARA – Qualificação e Caracterização da Pesca e do Pescado da Baía de Guanabara
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- Mar 2018
- QUALIPESCA GUANABARA – Qualificação e...
Update
Beatriz Corrêa
Orientadores: Marcelo Vianna e José Lailson-Brito Junior
Dissertação de Mestrado submetida ao Programa de Pós-graduação em Biodiversidade e Biologia Evolutiva, Instituto de Biologia, da Universidade Federal do Rio de Janeiro - UFRJ, como parte dos requisitos necessários à obtenção do título de Mestre em Biodiversidade e Biologia Evolutiva.
RESUMO
A conservação das espécies de elasmobrânquios tem sido o principal tema de discussão relacionado ao grupo nas últimas décadas. Planos de manejo estão sendo elaborados por diversos países e várias espécies passaram a ser consideradas oficialmente ameaçadas de extinção. Apesar disso, estudos sobre a contaminação desses organismos por organoclorados só se tornaram mais frequentes nos últimos anos. Incluídos no grupo dos Poluentes Orgânicos Persistentes (POPs), esses contaminantes são capazes de bioacumular e biomagnificar ao longo da teia trófica, sendo particularmente tóxicos para organismos topo de cadeia, como os elasmobrânquios. Em concentrações elevadas essas substâncias são capazes de provocar alterações nos sistemas endócrino e imune dos organismos marinhos, prejudicando sua reprodução e deixando-os vulneráveis a uma série de doenças. Esse estudo analisou a concentração de compostos organoclorados em fígado da raia-santa (Rioraja agassizi), uma espécie explorada comercialmente e classificada como “vulnerável” na Lista Vermelha de Espécies Ameaçadas da IUCN. A contaminação de R. agassizi foi considerada elevada. A concentração média de ∑PCB, o principal grupo de compostos organoclorados, foi de 560,5 (± 539,2) ng.g-1 de lipídio. Esse valor foi semelhante aos encontrados para algumas espécies de elasmobrânquios capturadas no Mar Mediterrâneo e para a população da raia Dasyatis sabina, do Golfo do México, que apresentou alterações nos sistemas endócrino e imune. Apesar da menor contribuição do DDT (∑DDT/∑PCB = 0,08), a análise de seus derivados indica uma entrada recente desse composto na área de estudo (DDE/∑DDT = 0,40). Indivíduos adultos apresentaram níveis mais elevados de poluentes em relação aos jovens. Não foram encontradas diferenças estatisticamente significativas entre machos e fêmeas. A existência de dois perfis de contaminação pode indicar a formação de agregações de indivíduos na população estudada.
Palavras-chave: Rioraja agassizi, Rajidae, Elasmobrânquios, Poluentes Orgânicos Persistentes
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Project - QUALIPESCA GUANABARA – Qualificação e Caracterização da Pesca e do Pescado da Baía de Guanabara
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- Feb 2018
- QUALIPESCA GUANABARA – Qualificação e...
Update
Luiza Chieza Fortes Garcia
Monografia apresentada ao Departamento de Biologia Marinha para obtenção do Diploma de Biólogo – Habilitação Bacharelado em Biologia Marinha – Instituto de Biologia – UFRJ
Orientador: Prof. Dr. Marcelo Vianna
Co-orientadora: Juliana Fukuda
RESUMO A pesca de siris constitui uma atividade de grande importância social e econômica na APA de Guapi-Mirim, na Baía de Guanabara. O objetivo desse estudo foi caracterizar essa pescaria, identificando a composição da captura que possui o siri-mirim (Callinectes danae) como espécie alvo e avaliar a sustentabilidade da mesma através da metodologia desenvolvida por uma eco-certificadora. Entre julho de 2014 e julho de 2015, 26 pescadores foram consultados através de entrevistas estruturadas, 64 puçás foram medidos e a composição da captura foi identificada em 26 amostras. Dados primários e secundários embasam a avaliação de sustentabilidade pela metodologia da SeaFood Watch®. Esse programa de certificação independente considera o impacto da pesca no estoque alvo, na fauna acompanhante e no ecossistema, além da efetividade do gerenciamento da pesca, que recebe uma das três recomendações em relação ao seu consumo: “melhor escolha”– pescarias que causam pequeno dano ao habitat e outros organismos, “boa alternativa”– compre, mas esteja ciente que existe preocupação com a forma que o item é capturado ou ”evitar” – não compre, por enquanto, ele está sobrepescado ou é capturado de maneira que prejudica o ecossistema. Os resultados indicam que 100% dos pescadores são homens, a maioria tem de 36 e 46 anos de idade (42,31%), mora em Itaoca (38,46%), começou a pescar siri entre 5 e 15 anos de idade (76,92%) e também trabalha em outro setor ou pescaria para complementar o renda (61,54%). A maioria possui entre 31 e 41 puçás (38,46%). O petrecho apresentou, em média, 34,4 mm de malha, entre nós adjacentes, com IC (α=0,05) de 3,3mm. A média do diâmetro do aro foi de 47,7 cm, com IC de 28,3 cm. A isca utilizada é pescoço de galinha, bagre ou outro peixe de baixo custo. As características do petrecho e o relato dos pescadores indicam que não há pesca fantasma. O período de maior frequência da pescaria é a manhã. Mesmo providos de remo, 57,7% se locomovem entre o local de captura e desembarque com motor. O principal destino da produção é a venda para o atravessador (46%), com preço médio de C. danae de R$ 2,75/kg para o siri inteiro e R$ 20,75/kg para o descarnado. Geralmente o pescador escolhe rios (23,08%) ou baía (50%) para pescar e raramente transita entre as duas áreas (26,92%). Essa escolha reflete a espécie-alvo desejada, pois C. danae é capturado na baía, onde também ocorre C. ornatus, enquanto C. sapidus, C. bocourti e C. exasperatus predominam nos rios. A pescaria cujo alvo é o siri-mirim e é composta por C. danae (88,75%; ♂595:♀17), C. sapidus (5,36%; ♂25:♀11), C. ornatus (5,22%; ♂35:♀2) e C. bocourti (0,72%; ♂2:♀3), sem descarte. Das fêmeas de C. danae, 58% estavam maduras, mas apenas uma tinha a largura da carapaça dentro do tamanho mínimo de captura, pois a legislação em vigor superprotege a espécie. O resultado da avaliação de sustentabilidade foi positivo em relação ao consumo e atingiu a recomendação de “melhor escolha”. Além de verificar o potencial da pescaria para uma possível certificação, a avaliação pode atuar como diagnóstico para orientar a definição de políticas públicas de gestão e conservação.
ABSTRACT The swimming crab fishing is an activity of great social and economic importance in Guapi-Mirim Environmental Protected Area, in Guanabara Bay. The aim of this study was to characterize this fishery, identifying catch composition from those that capture the “siri-mirim” (Callinectes danae) as target specie and assess its sustainability through the methodology developed by an eco-certification. Between July 2014 and July 2015, 26 fishermen were consulted through structured interviews and 64 traps were measured. The catch composition was identified in 26 samples. Primary and secondary data underpin the sustainability assessment methodology proposed by the SeaFood Watch®. This independent certification program considers the impact of fishing on target stock, the retained species and ecosystem, in addition to the effectiveness of fisheries management to evaluate the product. Based on these criteria, each fishery receive one of the three recommendations in relation to their consumption, "best choice" - fisheries that cause little damage to habitat and other organisms, "good alternative" - buy, but be aware that there is concern about the way that item is captured or "avoid" - do not buy for now, it is overfishing or is captured so that damages the ecosystem. The results indicated that 100% of fishermen are men, most have between 36 and 46 years old (42.31%), lives in Itaoca (38.46%), started to fish swimming crab between 5 and 15 years old (76.92%) and also works in another sector or fishing to supplement income (61.54%). Most has between 31 and 41 traps (38.46%). The gear had 34.4 mm of average mesh between adjacent nodes, with confidence interval (CI) (α = 0.05) equal to 3.3. The average diameter was 47.7 cm, with IC = 28.3 cm. The bait used is chicken neck, catfish or other inexpensive fish. The gear features and reporting of fishermen indicate that there is no ghost fishing. The higher frequency of fishing time is during the morning. Even equipped with rowing, 57.7% move around between the place of capture and landing with motor assistance. The main destination of production is selling to middlemen (46%), with an average price of R$ 2.75/kg for whole C. danae and R$ 20.75/kg for it stripped. Usually the fisherman chooses rivers (23.08%) or bay (50%) to fish and rarely move between the two areas (26.92%). This choice reflects the desired target species, because C. danae is caught in the bay, where also occurs C. ornatus, while C. sapidus, C. bocourti and C. exasperatus predominate in the rivers. The fishery which targets is “siri-mirim” consists of C.danae (88.75%; ♂595: ♀17), C. sapidus (5.36%; ♂25: ♀11), C. ornatus (5, 22%; ♂35: ♀2) and C. bocourti (0.72%; ♂2: ♀3). There is no rejected. Among the females of C. danae, 58% were ripe, but only one had the carapace width within the minimum landing size, because the current legislation overprotect the species. The result of the assessment of sustainability was positive in relation to consumption and reached the recommendation of "best choice". In addition to verifying the potential of the fishery for a possible certification, assessment may serve as a diagnostic to guide the definition of public policy management and conservation.
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Project - Estrutura e Funções do ecossistema da Baia de Guanabara: uma Pesquisa Ecológica de Longa Duração
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- Feb 2018
- Estrutura e Funções do ecossistema da Baia de...
Update
THAÍS RODRIGUES MACIEL
Dissertação apresentada ao programa de pós-graduação em ecologia da Universidade Federal do Rio de Janeiro, como parte dos requisitos necessários à obtenção do grau de Mestre em ecologia.
Orientador: Prof. Dr. Marcelo Vianna
Coorientador: Prof. Dr. André Martins Vaz dos Santos
RESUMO GERAL
Genidens genidens é uma espécie particularmente suscetível, assim como outros ariídeos, à sobrepesca, devido aos seus complexos mecanismos de ciclo de vida, que resultam em uma reposição lenta dos estoques. Desta forma, neste estudo objetivamos gerar dados sobre os custos que o cuidado parental acarreta sobre o crescimento do bagre G. genidens no estuário da Baía de Guanabara, fornecendo subsídios para o manejo pesqueiro adequado da espécie. Para tal, foi realizada uma análise cientométrica com o objetivo de investigar se o cuidado parental é comum em espécies estuarinas. Para investigação da biologia reprodutiva da espécie foi determinada sua razão sexual, fecundidade, tamanho de primeira maturidade sexual e período reprodutivo. Foi estudada ainda a ocorrência de dimorfismo sexual no padrão do crescimento relativo da espécie, através da relação comprimento-peso e da relação tamanho do corpo-tamanho do otólito. Os parâmetros de crescimento da espécie foram estimados a partir da leitura de anéis de crescimento nos otólitos. Nossos resultados demonstraram que o cuidado parental é comum em espécies estuarinas, uma vez que neste ambiente com alta flutuabilidade ambiental e com grande risco de predação, ele garante maior sobrevivência da prole. Na Baía de Guanabara as fêmeas de G. genidens foram mais abundantes que os machos. Os machos se tornam adultos em comprimento maior que as fêmeas (respectivamente, C50 = 17,55 cm e 15,9 cm). O período reprodutivo da espécie ocorre do fim da primavera ao início do outono, com um evento de desova e baixa fecundidade. Foi averiguado dimorfismo sexual na espécie relacionado às medidas morfométricas de seus otólitos. Os custos do cuidado parental, que impedem que os machos se alimentem por um período prolongado, se refletiu da relação peso-comprimento entre os sexos, onde os machos apresentam menor peso com o mesmo comprimento que as fêmeas. As fêmeas crescem de forma mais lenta que os machos e apresentam maturação mais tardia, atingindo assim maiores tamanhos corporais como estratégia para aumentar sua fecundidade. Desta forma, foi demonstrado que a biologia reprodutiva influencia o crescimento da espécie, criando dimorfismo entre machos e fêmeas, devido aos custos do cuidado parental, sugerindo-se que as medidas de ordenamento pesqueiro considerem essas particularidades da espécie.
Palavras chave: estuários; cuidado parental; otólitos; Baía de Guanabara.
ABTRACT
Genidens genidens is a specie, as well as other ariídeos, particularly susceptible to overfishing because of their complex life cycle mechanisms that result in a slow stock replenishment. Thus, this study aimed to generate data about costs that parental care brings to the growth of catfish the G. genidens in the estuary of Guanabara Bay, providing subsidies for proper fisheries management of the species. For such a scientometric analysis was performed in order to investigate if parental care is common in Estuarine Species. To investigate the reproductive biology of the species, we determined its sex ratio, fecundity, first sexual maturity and reproductive period size. It was also studied the occurrence of sexual dimorphism in the species standard relative growth through the length-weight relationship, and the body size ratio-otolith size relationship. The growth parameters of the specie were estimated from reading growth rings in the otoliths. Our results demonstrated that parental care is common in Estuarine Species, since this environment with high environmental fluctuation and great risk of predation, it ensures greater survival of offspring. In Guanabara Bay the females of G. genidens were more abundant than males. The males become adult in greater length than females (respectively, C50= 17,55 cm and 15,9 cm). The reproductive period of the species occurs from late spring to early autumn, with one spawning event and low fecundity. It was showed sexual dimorphism in the species related to morphometric measures of their otoliths. Parental care costs, which prevents the males feed for an extended period, reflected the length-weight relationship between the sexes, where males have less weight with the same length than females. Females grow more slowly than males and mature later, reaching thus larger body sizes as a strategy to increase their fertility. Thus, it was demonstrated that the reproductive biology influences the growth of the species, creating dimorphism between males and females due to parental care costs, suggesting that the fisheries management measures should consider these peculiarities of the species.
Keywords: estuaries; parental care; otolith; Guanabara Bay.
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Project - Sea Around Us
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- Feb 2018
- Sea Around Us
Update
Sérgio Ricardo Brito Santos
Tese apresentada ao Programa de Pós-Graduação em Biodiversidade e Biologia Evolutiva do Instituto de Biologia da Universidade Federal do Rio de Janeiro, como parte dos requisitos necessários à obtenção do título de Doutor em Biodiversidade e Biologia Evolutiva.
Orientador: Prof. Dr. Marcelo Vianna
RESUMO
A presença de pescadas e linguados, com suas variações, na estatística pesqueira brasileira tem representado um complexo problema que envolve a falta de identificação taxonômica, a grande variação regional e o acompanhamento falho por parte das agências públicas. A tese avaliou os impactos da ausência de um sistema de recolhimento específico de dados de desembarque para o conhecimento científico de duas categorias de pescado: pescadas/pescadinhas e linguados, levantar as espécies que atualmente são identificadas pelos nomes de referência e resgatar informações morfomerísticas capazes de serem tratadas como caracteres diagnósticos de fácil acesso. Para isto, uma análise cientométrica foi executada para doze espécies de Cynoscion e onze de Paralichthys, com ocorrência no Atlântico Ocidental pra explorar a evolução do conhecimento e tópicos abordados entre 1945 e 2015. Concomitantemente, foram visitados 14 pontos da costa fluminense com desembarque artesanal e quatro de desembarque industrial, entre 2013 e 2016, para registrar as espécies capturadas sob esses nomes vulgares. Um total de 500 artigos foram identificados para Cynoscion, com a espécie mais estudada sendo Cynoscion nebulosus (213 documentos), C. regalis (125), C. guatucupa (87) e C. arenarius (51). Foram identificados 414 artigos focados em Paralichthys com predominância de duas espécies, ambas com ocorrência do Canadá ao EUA, Paralichthys dentatus (46,1% dos estudos) e P. lethostigma (32,1%). A terceira espécie mais estudada foi P. orbignyanus (11,7%), restrita do Brasil a Argentina. O resultado mostrou que a maioria dos estudos publicados, não apenas para a área da ciência pesqueira, foram fundamentados em levantamentos biológicos, sendo que mais da metade fizeram uso de dados de coleta oficiais para estoques monoespecíficos. Enquanto a maior parte dos estudos corresponderam a pesquisas de curta duração, de até três anos, todos os estudos de longa duração, acima de seis anos, foram necessariamente baseados em dados de desembarque ao nível de espécie, como foi observado para C. guatucupa, no Atlântico Sul, C. nebulosus, C. regalis, P. dentatus e P. lethostigma no Atlântico Norte e Golfo do México. Dessa forma, a presença considerável da pesca artesanal ao longo da costa brasileira e dos demais países tropicais, com a dificuldade inerente de monitoramento dessa pescaria, bem como a ampla variedade de nomes vulgares presente nos dados de produção, sem a devida correspondência taxonômica, limitaram o uso e a confiabilidade dos dados de captura dessas áreas. Foram obtidos 395 exemplares de dez espécies de pescado sob a categoria pescada e variações e 176 exemplares de quatro espécies registrados sob a categoria linguado. Enquanto a análise variada canônica afastou consideravelmente I. parvipinnis e M. hubbsi das demais pescadas, baseados no comprimento das nadadeiras dorsal e anal, o restante foi agrupado em três grupos, caracterizados pelo formato da cauda, perfil dorsal da cabeça e posicionamento da nadadeira pélvica em relação a peitoral e a cabeça. A análise para linguados identificou que o formato da cauda e o posicionamento relativo do olho e maxilar foram de grande importância para a separação das espécies.
ABSTRACT
The presence of weakfishes and flatfishes, with their variations, in the Brazilian fishery statistics has represented a complex problem that involves the lack of taxonomic identification, the great regional variation and the flawed monitoring strategy by the public agencies. The thesis evaluated the impacts of the absence of a species-level landing data collection system for the scientific knowledge of the two categories, to record the species that are currently identified by the reference names weakfishes and flatfishes and to recover morphomeristic information capable of being treated as easily accessible diagnostic characters. For this, a scientometric analysis was performed for eleven species of Paralichthys and twelve species of Cynoscion, occurring in the Western Atlantic to explore the evolution of knowledge and topics covered between 1945 and 2015. Concomitantly, 14 points of the coast of Rio de Janeiro with artisanal landing and four with industrial landings were visited between 2013 and 2016 to record the species caught under these common names. A total of 414 papers focused on Paralichthys with predominance of two species, both with occurrence from Canada to the USA, Paralichthys dentatus (46.1% of the studies) and P. lethostigma (32.1%). The third species most studied was P. orbignyanus (11.7%), restricted from Brazil to Argentina. A total of 500 articles were identified for Cynoscion, with the most studied species being Cynoscion nebulosus (213 documents), C. regalis (125), C. guatucupa (87) and C. arenarius (51). The results showed that most of the studies published, not only in the field of fisheries science, were based on biological surveys, with more than half using official collection data for monospecific stocks. While most studies corresponded to short-term surveys of up to three years, all long-term studies over six years were necessarily based on species-level landing data, as observed for C. guatucupa, In the South Atlantic, C. nebulosus, C. regalis, P. dentatus and P. lethostigma in the North Atlantic and Gulf of Mexico. Thus, the considerable presence of artisanal fishing along the Brazilian coast and other tropical countries, with the inherent difficulty of monitoring this fishery, as well as the wide variety of common names present in the production data, without due taxonomic correspondence, limited the use and reliability of catch data from these areas. A total of 395 specimens were obtained for ten fish species under the category weakfishes and variations and 176 specimens of four species registered under the category flatfishes. While the canonical analysis considerably removed I. parvipinnis and M. hubbsi from the other weakfishes, based on the length of the dorsal and anal fins, the remainder were clustered into three groups, characterized by the tail shape, dorsal head profile and pelvic fin position in relation to the pectorals and head. The analysis for flatfishes identified that the tail shape and the relative positioning of the eye and jaw were of great importance for the separation of the species.
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Project - QUALIPESCA GUANABARA – Qualificação e Caracterização da Pesca e do Pescado da Baía de Guanabara
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- Feb 2018
- QUALIPESCA GUANABARA – Qualificação e...
Update
PROPOSTAS PARA O MANEJO PESQUEIRO ECOSSISTÊMICO DA BAÍA DE GUANABARA
LUANA PRESTRELO PALMEIRA
Tese apresentada ao programa de pós-graduação em ecologia da Universidade Federal do Rio de Janeiro, como parte dos requisitos necessários à obtenção do grau de doutora em ciências biológicas (ecologia). Defendida em 07 de junho de 2017
Orientador: Prof. Dr. Marcelo Vianna
RESUMO
A importância do manejo da pesca de pequena escala (PPE) inclui a manutenção dos ecossistemas, segurança alimentar e diminuição da pobreza, principalmente nos estuários, porém as estratégias tradicionais são ineficazes. A multidisciplinaridade da PPE precisa ser considerada numa abordagem ecossistêmica do manejo pesqueiro. Este trabalho objetivou desenvolver diretrizes para o manejo ecossistêmico estuarino, com estudo de caso na Baía de Guanabara. Primeiro foram identificadas as principais estratégias de manejo da PPE pelo mundo e a inclusão do zoneamento, utilizando a cientometria. Áreas marinhas protegidas e direito ao uso do território pelos pescadores foram as medidas mais frequentes. Elas nem sempre atingem seus objetivos, principalmente devido a abordagem unidimensional (ambiental e econômica, respectivamente). Outro fator crucial no fracasso do manejo tradicional foi a exclusão dos pescadores do processo. O manejo por zonas, apesar de fundamental, é incipiente. Segundo, foram analisados padrões tecnológicos das embarcações através de análises de correspondência. Foram identificadas diferentes unidades de manejo estuarinas para serem consideradas na gestão pesqueira. A baixa tecnologia das embarcações promove a utilização de diversos petrechos que, somado ao perfil de sobreposição de recursos-alvo, dificulta medidas de manejo espécie ou petrecho-específicas. O manejo estuarino precisa se basear nestas unidades de manejo, contrapondo-se aos métodos tradicionais. Terceiro, foram identificados conflitos espaciais entre a pesca e outras atividades, sobrepondo mapas mentais desenvolvidos pelos pescadores e áreas de exclusão de pesca oriundas de diferentes regulamentações, utilizando a ferramenta de GIS. O caráter multi-legislativo do estuário resultou na sobreposição de áreas de exclusão impedindo a manutenção da pesca. O cerco e arrasto camaroneiro atuam exclusivamente em áreas proibidas e não são dependentes do estuário, sendo indicada a realocação para a zona costeira adjacente. A identificação de áreas de exclusão além das de cunho ambiental é rara, promovendo um zoneamento pesqueiro irreal. Por fim, foi avaliado o impacto e rendimento da PPE, identificadas categorias comerciais de pescado multiespecíficas e determinada a sustentabilidade dos petrechos, através do monitoramento dos desembarques, identificação taxonômica e análise multidisciplinar (Rapfish). Além de diferenças espaciais de captura entre os petrechos, foi observada diferença entre áreas de maior produção e maior rendimento do mesmo petrecho. Conhecer o valor de venda do pescado é crucial para identificar zonas de importância socioeconômica que diferem das de maior captura (de preocupação ambiental). Categorias multiespecíficas prejudicam estimativas de diversidade ambiental, avaliação dos estoques e o sucesso de medidas de manejo, principalmente de petrechos menos seletivos (emalhe) e áreas com maior diversidade (alto estuário). Aprimorar esta identificação é fundamental na avaliação do impacto pesqueiro no ecossistema como um todo, não só nos recursos-alvo como feito nas abordagens tradicionais. O curral fixo e emalhe são indicados para a PPE estuarina. Apesar da baixa sustentabilidade ecológica do curral, o desempenho de manejo foi capaz de superar as vulnerabilidades. O emalhe gera mais impacto e tem menor sustentabilidade, mas sua importância socioeconômica o torna essencial para comunidades locais. O aumento da capacidade de manejo poderá melhorar seu desempenho. O cerco apresentou a menor sustentabilidade, reforçando sua realocação.
Palavras-chave: Pesca de pequena escala; Manejo pesqueiro; Estratégia de pesca; Zoneamento; Impacto pesqueiro; Sustentabilidade pesqueira.
ABSTRACT
The importance of small-scale fisheries (SSF) management includes ecosystem maintenance, food security and poverty elevation. However traditional approaches are inefficient, principally in estuaries. The multidisciplinary feature of SSF needs to be considered in fisheries management. This study aimed to development guidelines to achieve an estuarine ecosystem approach, with Guanabara Bay as study case. First, the most used SSF management and zoning approaches were identified worldwide using the scientometric method. Marine protected areas and territorial use rights to fisheries were the main management approaches. However, they did not always achieve their goals, mainly due to their uni-dimensional features (environmental and economic). Other crucial factor responsible to traditional management failure was the omission of fishers from the process. Zoning management discussions were scarce, despite its importance. Second, vessels technological patterns were analyzed using correspondence analysis. Different management units were identified and must be considered in fisheries management. The low technology promotes the use of multiple gears and hampers species and gear-specific management approaches. This is aggravated by resources overlap. Thus, estuarine fisheries management must consider those units, opposing to the traditional approaches. Thirdly, spatial conflicts between fisheries and other activities were identified by overlapping mental maps developed by fishers with no-fishing zones from a variety of regulations. A GIS tool was used. Estuarine multi-legislative feature resulted in the impediment of fishing activity due to the overlap of several no-fishing zones. Purse seine net and shrimp trawling take place only in prohibited zones. Since they do not dependent upon the estuary, the reallocation of those gears to the adjacent coastal zone is indicated. The identification of regulations unconnected with environmental issues was common and its overlap resulted in the establishment of unreal fishing zoning. Lastly, the impact and income of SSF were evaluated; multi-specific fish commercial categories were identified; and the sustainability of fishing gears were determined through landing monitoring, taxonomic identification and a multidisciplinary analysis (Rapfish). We observed a spatial difference in catch among different gears, and spatial differences in catch and income within the same gear. Acknowledge fish value is crucial to identify important socioeconomic zones, which may differ from the important production zones (of environmental concern). Multi-specific fish categories impair environmental diversity, stock assessment and management success. Less selective fishing gears (gillnet) and more diversity areas (upper estuary) intensify that problem. Improving catch identification is crucial to assess the impacts of SSF in the ecosystem and not only in the target resource, as done by traditional management approaches. Stationary pound net and gillnet are indicated to operate in estuaries. Although the first showed low ecological sustainability, the strong management performance was capable to overcome the vulnerabilities. Gillnets generates more impact and have less sustainability, but its great socioeconomic importance makes it essential to local communities. Increasing management capacity could improve gillnet’s performance. Purse seine exhibited the lowest sustainability rate, strengthening its limitation to the coastal zone.
Key words: Estuaries; Small-scale fisheries; Fisheries management; Fishing tactics; Zoning; Fishing impacts; Fisheries sustainability.
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The majority of morphological abnormalities reported for elasmobranchs are cases of bicephalia. This contribution describes the third confirmed case worldwide and the first in the South Atlantic of diprosopus tetrophthalmus (craniofacial duplication) in a foetus of blue shark, Prionace glauca (Linnaeus, 1758), from a female caught off the Brazilian coast (26°36′11′′S, 45°56′00′′W) in July 2007. The specimen is described and compared to normal specimens from the same size and to another one with similar deformities from Chile. The embryo is smaller than a normal embryo, with deformities in the skull, head muscles and curvature of the vertebral column.
Project - QUALIPESCA GUANABARA – Qualificação e Caracterização da Pesca e do Pescado da Baía de Guanabara
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- Oct 2017
- QUALIPESCA GUANABARA – Qualificação e...
Update
RESUMO
PAIVA, Larissa Gouvêa. Compostos organoclorados em uma raia criticamente ameaçada, Gymnura altavela (LINNAEUS, 1758), no estuário da Baía de Guanabara, Rio de Janeiro, Brasil. 2015. 92 f. Dissertação (Mestrado em Oceanografia) – Faculdade de Oceanografia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2015.
Nos últimos anos, temas envolvendo a conservação de elasmobrânquios têm recebido maior atenção em muitos países. Muitas espécies passaram a ser consideradas ameaçadas de extinção pela IUCN, demonstrando a necessidade de ordenamento pesqueiro e elaboração de planos de manejo. Os Poluentes Orgânicos Persistentes correspondem a mais uma ameaça para esse grupo de peixes, no entanto, estudos envolvendo a contaminação desses organismos são recentes e vêm aumentando nos últimos anos. O presente estudo teve como objetivo principal a quantificação de compostos organoclorados em tecido hepático de uma espécie de raia criticamente ameaçada raia-borboleta, Gymnura altavela, residente na Baía de Guanabara, um dos ambientes estuarinos mais impactados do Brasil. Além disso, investigouse a influência de fatores biológicos, tais como estágio de maturidade sexual, sexo, tamanho e porcentagem de lipídio na matriz analisada, sobre os perfis de contaminação por esses xenobióticos. As concentrações dos compostos organoclorados foram determinadas com a utilização do cromatógrafo de fase gasosa com detector de captura de elétrons (CG-DCE), da marca Agilent Technologies, modelo 7890. Nossos resultados mostraram que as bifelinas policloradas (PCB) representam a classe mais importante de contaminantes com concentração média de 6.772,8 (± 4.659,4) ng.g-1 de lipídio e a maior concentração foi 18.513,1 ng.g-1 de lipídio em um indivíduo macho e jovem. Desse total, 66,5% foram representados pelos congêneres de PCBs 153>138>180>101>170. Quanto ao número de átomos de cloro, os PCBs pertences à classe dos hexa-clorados foram os mais abundantes. A concentração média do ΣDDT foi 646,0 (± 722,4) ng.g-1 de lipídio e o isômero mais representativo foi o p,p’ – DDE com 65,7% do total. O ΣHCH, o HCB e o Mirex representaram 0,13% da contaminação total em G. altavela sendo, portanto, os compostos com as menores contribuições. A razão representada pela fórmula ΣDDT/ΣPCB foi de 0,09, caracterizando uma predominância de compostos de origem industrial. As correlações de Spearman apontaram para uma diminuição das concentrações do ∑PCB, ∑HCH e Mirex à medida que os indivíduos crescem. Não foram encontradas diferenças nas concentrações em relação aos diferentes estágios de maturidade sexual e entre machos e fêmeas.
Palavras-chave: Compostos organoclorados. Contaminação. Baía de Guanabara. Gymnuridae. Gymnura altavela. Elasmobrânquios.
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- Ana Carolina Pizzochero
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- Loïc N Michel
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- Simon Robert Chenery
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- [...]
- Paulo Dorneles
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The whitemouth croaker, Micropogonias furnieri, is a long-lived fish of high commercial importance in the Western Atlantic Ocean. Here, we used stable isotope ratios of carbon, sulfur and nitrogen and isotopic niche metrics (SIBER) to study feeding habits and track habitat use by whitemouth croakers in Guanabara Bay, an estuary in Rio de Janeiro state, Brazil. Our results highlighted size-related habitat segregation, with small juvenile (< 30 cm) fishes residing mostly inside estuaries, while large adult (> 60 cm) fishes feed mainly in Continental Shelf (CS) waters. Medium adult fishes (30-60 cm) appear to feed in multiple coastal and CS habitats. Moreover, their feeding ecology showed strong temporal differences, linked with seasonal and, to a lesser extent, inter-annual variation in oceanographic features of the ecosystem in which they live. Overall, these differences in ecological features suggest that (1) adult and juvenile whitemouth croakers should be treated as different components of the food web and (2) the conservation of these habitats should be prioritized to better manage and sustain the coastal fisheries in Guanabara Bay.
A scientometric analysis was performed for 12 species of Cynoscion from the Western Atlantic to explore the evolution of knowledge and the topics covered between 1945 and 2015. The search was based on the total number of results found in two scientific platforms, ISI Web of Science and SciELO, with emphasis on the documents related to fisheries science. A total of 500 articles were identified, with the most-studied species being Cynoscion nebulosus (213), C. regalis (125), C. guatucupa (87) and C. arenarius (51). Fisheries sciences represent 14% of the literature for Cynoscion, which consists mainly of US and Brazilian documents, accounting for 85.9% of the 69 studies produced by 206 researchers affiliated with 64 institutions. The studies are mainly aimed at fisheries ecology, resource management, stock assessment and fish quality and are mostly (55.3%) based on up to three years of sampling. The considerable presence of artisanal fisheries along the Brazilian coast, the difficulty of monitoring this fishery, and the wide variety of common names that in the absence of taxonomic resolution are inserted in landings data make it impossible to identify which stocks are effectively exploited, limit the use of fish-catch data, and result in fewer fisheries studies.
The feeding ecology of five elasmobranch species was studied on the southern coast of Rio de Janeiro, southwestern Atlantic Ocean. The specimens were caught with a trawl or bottom longline between January 2006 and August 2007. The diets of Psammobatis rutrum and Psammobatis extenta appeared to be basically carcino-benthophagous, with a very small niche width. Rioraja agassizii was basically carcino/ichthyo-benthophagous, also with a narrow niche, including teleost fish and shrimp, but in different proportions according to age and sex. Rhizoprionodon lalandii was ichthyophagous, not influenced by age or sex. The analyses of these species and Atlantoraja cyclophora indicated two trophic groups: one composed of the smaller rays, P. extenta and P. rutrum, which basically fed on small crustaceans, polychaetes and nematodes; and the other of R. lalandii and the larger rays R. agassizii and A. cyclophora, which preyed on teleost fish and brachyurans.
- Apr 2017
The purpose of this paper is to assess the use of multi-elemental otolith fingerprints as a tool to delimit catfish Genidens barbus fish stocks in four estuaries from the southwestern Atlantic Ocean. Barium:Calcium (Ca), Magnesium:Ca, Manganese:Ca, Sodium:Ca and Strontium:Ca ratios in the otolith edge were determined by LA-ICPMS. PERMANOVA analysis reveal significant differences in the multi-element signatures among estuaries (p = 0.0001–0.002). Reclassification rates of quadratic discriminant analysis are high, averaging 89.9% (78–100%). The new data presented here show that the otolith chemistry is a potential tool for stock identification, and indicates the presence of at least four stocks which should probably be handled independently.
- Apr 2017
Catfish Genidens barbus is a commercially fished species from the southwestern Atlantic Ocean. Overfishing of this species during the last few years has caused a collapse of fisheries and in turn has led to a ban of its exploitation. In order to identify the migratory patterns of this species in four migration corridors from South America, we determined the Sr:Ca and Ba:Ca ratios in otoliths, by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICPMS). Sr:Ca and Ba:Ca ratios range between 0.90 and 9.83 mmol/mol (mean ± standard deviation: 3.86 ± 1.05 mmol/mol) and between 0.00013 and 0.10 mmol/mol (mean ± SD: 0.0094 ± 0.0160 mmol/mol), respectively. Three types of amphidromous and cyclical (annual) patterns that include the use of freshwater, estuarine and marine environments are detected. Resident freshwater fish (6.5%) are found only in Patos Lagoon. Depending on the study site, between 18 and 45% of the analyzed fish population were spawned in freshwater, while the rest were spawned in estuarine waters. The change-point analysis shows a positive correlation between changes in the transects of Sr:Ca and Ba:Ca ratios (r = 0.63, p = 0.0001), whereas the Kruskal-Wallis test shows no significant differences in the number of changes in transects of the Sr:Ca ratio between sampling sites (H = 2.1, p = 0.53). Only for Patos Lagoon the analyses show a significantly higher number of changes for the Ba:Ca ratio (H = 9.1, p = 0.03). The data indicate that the average number of movements among environments is similar between the four corridors. The number of changes of the Ba:Ca ratio appears to be higher and more variable in relation to the Sr:Ca ratio, indicating that the former could be more sensitive to environmental changes. In conclusion, this work describes for the first time, annual amphidromous migrations and dependence on freshwater for different fluvial-marine systems. The understanding of the habitat use will help design species and estuarine-specific management actions with the ultimate goal of recovering fisheries.
The anadromous catfish, Genidens barbus, is a commercial and vulnerable species from South America.
The aims of the present study were to assess whether the nursery areas can be discriminated by using microchemical signatures of lapillus otoliths, to assess the accuracy of classifying fish in relation to natal nursery area and to discuss the possibility of existence of homing behaviour. Thus, the otolith-core chemical signatures (barium (Ba) : calcium (Ca), lithium (Li) : Ca, magnesium (Mg) : Ca, manganese (Mn) : Ca, strontium (Sr) : Ca, and zinc (Zn) : Ca ratios) of adult fish were compared among different estuaries (De La Plata River in Argentina, and Patos Lagoon, Paranagua´ Bay and Guanabara Bay in Brazil). PERMANOVA analysis showed significant differences in the multi-element signatures of the otolith core among sampling sites for all cohorts (2002, 2003, 2006 and 2007), indicating that the technique has considerable potential for use in future assessments of population connectivity and nursery areas of G. barbus. Via quadratic discriminant function analysis, fish were classified to natal nursery areas with 80–100% cross-validation classification accuracies. These results suggested that a high level of spatial segregation exists in adult catfish life and homing behaviour could not be ruled out on the basis of our data.
This study focused on the infuence of local-scale environmental factors on key metrics of fish community structure and function at Guanabara Bay, an estuarine system that differs from all other south-western Atlantic estuaries due to the infuence of an annual low-intensity upwelling event during late spring and summer, between November and March, when a warm rainy climate prevails.The spatial patterns of the bottom temperature and salinity were more heterogeneous during the rainy season than the dry season, being linked to total precipitation and seasonal oceanographic events. The study identifed 130 species and 45 families, placing Guanabara Bay as one of the most species-richtropical estuarine ecosystems, far exceeding 22 other Brazilian estuaries. These results, in addition to characteristics such as a relatively well-preserved mangrove forest, high productivity and favourable conditions for the growth and reproduction of estuarine species, indicate that Guanabara Bay plays acentral role in supporting large populations of fishes, including commercially important species.
- May 2016
Marine spatial planning (MSP) is essential to solve spatial multiple-use problems, but first it is necessary to identify and map all existing uses, regulations and conflicts. Use conflicts related to the multi-legislative governance, neglect of fishermen's interests, and intensifying industrial growth due to economic development were identified for in a multiple-use Brazilian estuary. Overlaps between areas that are presently used for fishing and areas that are subject to regulations prohibiting this activity were analyzed. Information on regulations establishing no-fishing zones, the most important fishing sites and fishing records were gathered and superimposed using a GIS dataset. Main fishing zones were located within prohibited fishing areas. Regulations limiting fishing activity govern navigation routes and pipeline safety zone, whereas environmental law restrictions were less important. Due to economic and industrial development, oil and gas distribution and harbor construction projects are increasing, aggravating use conflicts and jeopardizing fishing activity. Legislation fragments usable fishing areas forcing fishers to operate within prohibited zones. Neglect of fishermen's interests, and their exclusion on the decision-making process led to a legislative scenario that reduce fishing legal zone to few areas, which in most cases fisherman are not even aware were they are, beingthe main reasons for fisher's failure to comply with the current regulations, increasing the number of infractions and the marginalization of fishermen. Future studies on multiple-use coastal areas subject to multiple jurisdictions should focus on all uses, not only environmental, to better understand spatial conflicts and to establish a realistic MSP embracing fisheries management, environmental conservation and economic development.
- Dec 2015
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.
This paper aims to study the ontogenetic sexual dimorphism of Genidens genidens in Guanabara Bay, southeastern coast of Brazil. Altogether 378 specimens were anayzed (233 females and 145 males) with total length ranging from 13.3 to 43.5 cm. Specimens were measured for 12 body measurements, sex was identified and maturity stages were recorded and classified. Pearson’s linear correlation reveled a significant positive correlation between total length and all other body measures, except for base adipose fin, mouth depth and eye depth for immature females. Analyses nested PERMANOVA desing showed significant differences between maturity stages for each sex, between sexes considering or not maturity stages, indicating a variation in morphometric characteristics driven by sexual dimorphism. Differences among all maturity stages were also found, indicating an ontogenetic morphological difference. But immature individuals didn’t differ between sexes indicating that differentiation patterns starts with sexual development. The most important measures differing males and females were related to head characteristics, which appears to be key parameters to evaluate sexual differences. Due to male incubation of fertilized eggs and juvenile individuals <59 mm in their oral cavity, head measures are proposed to be sex dimorphism not related to reproduction, but with post reproductive fase due to ecological and biological needs.
Sampling of the demersal ichthyofauna of Guanabara Bay was conducted bimonthly for 2 years at 10 stations distributed along a hydrobiological gradient. A total of 16,081 Tetraodontiformes specimens were collected, representing 10 species distributed among Ostraciidae, Monacanthidae, Tetraodontidae and Diodontidae. Tetraodontiformes appear to be well adapted to hydrological variations and inhospitable conditions prompted by intense eutrophication. However, abiotic factors traditionally considered important in estuarine community structure play a secondary role in the distribution of Tetraodontiformes. The type of sediment appears to be the most important physical factor but acts only as an indicator of ecological domain. The low explanatory power of physicochemical variables, in addition to the relative stability of the bay’s ichthyofauna, suggests an influence of biological parameters. The species exhibited wide variation in their use of Guanabara Bay and utilized it as a resting, feeding and growing area. Among the species captured, Stephanolepis hispidus, Lagocephalus laevigatus, Sphoeroides greeleyi, Sphoeroides testudineus, Sphoeroides tyleri, Chilomycterus reticulatus and Chilomycterus spinosus were categorized as marine estuarine opportunists, and Aluterus heudelotii and Aluterus schoepfii were classified as marine stragglers. Acanthostracion sp. could not be categorized. The boom of C. spinosus indicates an ecological misbalance and must be carefully investigated.
Guanabara Bay is one of the most ecologically, economically and socially important tropical estuaries in the southwestern Atlantic. Fortnightly samples of the demersal ichthyofauna were obtained from July 2005 to June 2007, by bottom trawling from six stations determined according to the water quality. The net was 7 m long with a 14 m wide mouth and a mesh size of 18 mm. The tows were made at a speed of about 1.5 knots. The most abundant species, occurring in all 48 surveys, was Chilomycterus s. spinosus (14,837 specimens; 61.8 ind/h; 3.85 kg/h). Although commonly captured in Brazilian bays, this species has never been found in such high abundance and wide LT ranges (2.6�35.6 cm). The fish were concentrated in the middle portion of the estuary, which shows their high tolerance to eutrophic conditions, as well as to natural variations in temperature and salinity. In the last quarter of the study, the relative abundance levels rose to 228 ind/h, mostly small specimens of about 8.0 cm LT and 40 g MT, comprising 45% of the total catch. Such a successful recruitment could cause a large shift in species composition in the demersal community, with unpredictable ecological consequences. The population fluctuations of this species coincided with the rainfall pattern; the estuary is used as a nursery area until the fish reach the size at first maturity.
- Jul 2015
The whitemouth croaker (Micropogonias furnieri) is the main fish species of the demersal fisheries along the Atlantic coast of South America. There has been much debate regarding the number of stocks of this heavily exploited fish off the Brazilian coast between latitudes 23 • S and 33 • S. Analyses of morphometric and meristic data suggest that two stocks exist in that area, but this conclusion was not supported by genetic studies. Here, we used polymorphic nuclear loci (microsatellite and intron size polymorphisms) to compare samples of M. furnieri collected between Rio de Janeiro (23 • 02 S) and Chuí (33 • 41 S), as well as samples from much further north, along the coast of Braganç a at Pará State (1 • 03 S). Our data demonstrate the existence of three distinct stocks of the species in Brazil: one in North Brazil (Braganç a – Pará State), as previously suggested; and two previously not detected genetically: one between 23 • S and 29 • S; and another south of parallel 29 • S. These findings indicate that the fisheries of the three areas should be managed as distinct stocks.
A primeira lista da fauna brasileira ameaçada de extinção incluía 42 espécies de répteis, aves e mamíferos (IN IBDF 303/1968). Esse número duplicou cinco anos depois, quando 85 espécies, entre elas o primeiro invertebrado terrestre ameaçado no país, integraram a lista seguinte (IN IBDF 3.481/1973; Quadro 1). Passados 16 anos, a lista quase triplicou, com 219 espécies de vertebrados (exceto os peixes), além de alguns invertebrados terrestres (Portaria Ibama 1.522/1989).
Catch data are the most basic information to be collected for managing fisheries everywhere. However, in many regions around the globe, including Brazil, this information is not available in a quality that is satisfactory. The objective of the initiative presented in this paper was to compile a country-wide database of marine commercial catch data in its original form (landings only) and a reconstructed version (which includes artisanal, industrial, recreational, and subsistence landings, as well as major discards), as well as to analyze historical trends. The basis for the country-wide database of marine catch statistics compiled here were the national official bulletins published in Brazil for the period 1950 to 2010. They represent an update of previous databases compiled for 1980-2000 and later for 1950-2004. These databases were revised and extended to include the whole period from 1950 to 2010 and all 17 coastal states in Brazil, from Amapá to Rio Grande do Sul. Estimates for recreational and subsistence catches and discards were added. Our analysis indicates that total catches for Brazil may be almost 2 times the baseline reported for Brazil. Besides the previously known low taxonomic resolution of catch statistics in Brazil, taxonomic losses were observed when local data were incorporated into the national bulletins and later in the FAO database (FishStatJ). Regional analyses indicate that the highest catches are associated with the southern region, except when there is a peak in sardine catches. However, this result may be biased as those values may include catches off
the southeastern region that end up being landed in the south. The same is true for other regions in Brazil. Sardine and demersal fishes comprise the largest portion of the catches. This reconstruction is preliminary and should be revised by local experts to improve the local database and hence the national and global databases
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.
The Brazilian Minister of the Environment released the new national red lists enumerating 2113 plants and 1173 animals threatened with extinction. Of the 475 aquatic species on the list, 83 are commercially exploited by fisheries, mainly as by-catch. The industrial fisheries sector is now using its political influence to persuade the government to change the contents of the list of aquatic animals or revoke it entirely.
Fishing and oil drilling compete for space in some regions off the Brazilian coast. Fish congregate around drilling platforms, which attracts fishing vessels that may illegally breach the 500 m safety perimeter. The objective of this study was to identify the fleets that frequent the safety zone of a platform and their behavior and to determine if there was a seasonal relationship in this interaction, during two exploration campaigns, in different periods, carried out on the "Ocean Star" platform in the Espírito Santo Basin. The results indicated a high incidence of artisanal fishing vessels inside the prohibited area, and of uncooperative behavior on the part of the boat crews. The statistical method of Factorial Correspondence Analysis distinguished vessels that were using pelagic longlines to fish for dolphinfish, registered in the state of Espírito Santo and longer than 11 m, which operated during the summer campaign. Vessels fishing for scombrids, which were less than 11 m long and registered outside Espírito Santo, were prominent in the autumn-winter campaign. In conclusion, the data showed that the fleets involved in each exploratory campaign were different, but to determine the real reason why the boats insist on frequenting the area close to the platform further study is necessary.
A Baía de Guanabara é um ambiente estuarino reconhecido como importante polo pesqueiro para o estado do Rio de Janeiro, apresentando incontestável valor social e econômico. Este estudo teve como objetivos analisar e apontar se a legislação brasileira possui medidas que correspondem a um ordenamento adequado da atividade pesqueira nesse ecossistema costeiro e seus recursos pesqueiros e, em caso negativo, indicar mudanças necessárias para tornar mais apropriada à aplicação dessas normas jurídicas. O levantamento e análise das normas jurídicas foram desempenhados entre agosto de 2010 e junho de 2011, usando dois eixos temáticos: (I) Proteção à Zona Costeira e (II) Medidas de Ordenamento. O levantamento da legislação pesqueira aplicada à Baía de Guanabara resultou em 214 normas jurídicas, divididas entre os eixos I e II em 60% e 40%, respectivamente. Divergências ou ausência de medidas de ordenamento foram causadas por problemas com a redação oficial ou com a abrangência das normas jurídicas, demonstrando ausência de medidas de ordenamento para alguns recursos pesqueiros na área de estudo. Conclui-se que para a legislação contemplar plenamente a atividade pesqueira na Baía de Guanabara se faz necessária a adequação das normas jurídicas existentes a partir de ajustes, considerando novas espécies de pescado, conceituando o termo águas interiores e adotando áreas de pesca, assim como as demais definições dadas pela Política Nacional de Desenvolvimento Sustentável da Aquicultura e Pesca. ABSTRACT The Bay of Guanabara is an estuarine environment recognized as an important fishing pole for the state of Rio de Janeiro, with undisputed social and economic value. This study aims to analyze and pinpoint whether the Brazilian legislation has measures that correspond to a sustainable ordering of fishing activity in this coastal ecosystem and its fishery resources and, if not, indicate necessary changes to make it suitable to the application of these legal norms. The survey and analysis of legal standards were performed between August 2010 and June 2011, using two themes: (I) Protection of the Coastal Zone and (ii) Fishing management. The survey of fisheries legislation applied to Guanabara Bay resulted in 214 legal standards, divided between the axes I and II in 60% and 40% respectively. Differences or lack of management measures were caused by problems with the writing or the official coverage of legal standards, some fish stocks were being harmed by these failures further aggravating the species that have overexploited and vulnerable to extinction. Concluding that the legislation analyzed contemplates fishing in Bay of Guanabara, but an adaptation of existing legal rules is necessary in view new species, conceptualizing the term inland waters and adopting other definitions given by the National Policy for the Sustainable Development of Aquaculture and Fisheries.
Catch data are the most basic information to be collected for managing fisheries everywhere.
However, in many regions around the globe, including Brazil, this information is not available with
satisfactory quality. The objective of the initiative described in this paper was to compile a countrywide
database of marine commercial catch data in its original form (only landings) and a
reconstructed version (which includes artisanal, industrial, recreational, and subsistence landings, as
well as major discards) and to analyze historical trends. The basis for the country-wide database of
marine catch statistics compiled here were the national official bulletins published in Brazil for the
period 1950 to 2010. They represent an update of previous databases compiled for 1980-2000 and
later for 1950-2004. These databases were revised and extended to include the whole period from
1950 to 2010 and all 17 coastal states in Brazil, from Amapá to Rio Grande do Sul. Estimates for
recreational and subsistence catches, and discards were added. Our analysis indicates that total
catches for Brazil may be almost 2 times the reported baseline determined for Brazil. Besides the
previously known low taxonomic resolution of catch statistics in Brazil, taxonomic losses were
observed when local data were incorporated into the national bulletins and later in the FAO database
(FishStat J). Regional analyses indicate that the highest catches are associated with the southern
region, except when there is a peak in the production of sardine. However, this result may be biased
as those values may include catches off southeastern region that end up being landed in the south.
The same is true for other regions in Brazil. Brazilian sardine and demersal fishes comprise most part
of the catches. The present reconstruction may be viewed as preliminary and could be revised by local
experts to improve the local database and hence the national and global databases.
The stomach contents of the eyespot skate, Atlantoraja cyclophora (Regan, 1903), were examined with the
goal to provide information about the diet of the species. Samples were collected off the southern coast of Rio de Janeiro, Brazil, near Ilha Grande, between January 2006 and August 2007, at a depth of about 60 m. The diet was analyzed by sex, maturity stages and quarterly to verify differences in the importance of food items. The latter were analyzed by: frequency of occurrence, percentage of weight and in the Alimentary Index. The trophic niche width was determined to assess the degree of specialization in the diet. Additionally, the degree of dietary overlap between males and females; juveniles and adults and periods of the year were defined. A total of 59 individuals of A. cyclophora were captured. Females and adults were more abundant. The quarters with the highest concentrations of individuals were in the summer of the Southern Hemisphere: Jan-Feb-Mar 06 and Jan-Feb-Mar 07. Prey items were classed into five main groups: Crustacea, Teleosts, Elasmobranchs, Polychaeta, and Nematoda. The most important groups in the diet of the eyespot skate were Crustacea and Teleosts. The crab Achelous spinicarpus (Stimpson, 1871) was the most important
item. The value of the niche width was small, indicating that a few food items are important. The comparison of the diet between males and females and juveniles and adults indicates a significant overlap between the sexes and stages of maturity; and according to quarters, the importance of prey groups differed (crustaceans were more important in the quarters of the summer and teleost in Jul-Aug-Sep and Oct-Nov-Dec 06), indicating seasonal differences in diet composition. Three groups with similar diets were formed in the cluster analysis: (Jan-Feb-Mar 06 and 07); (Apr-May-Jun 06 and Jul-Aug-Sep 07); (Jul-Aug-Sep 06 and Oct-Nov-Dec 06).
The fishing activity in the state of Rio de Janeiro is reflected in a fleet formed, mostly, by vessels poorly sized and older. Taking into account the lack of knowledge about the state of the coastal fleet Rio de Janeiro, the present study aimed to characterize the vessels; identify sub-fleets presents; describe and compare these fleets and seek to understand the role of environmental, socioeconomic and cultural characteristics on the spatial arrangement of the vessels. For the study, the structural characteristics of the vessels were collected along the coastal physiographic compartments of Rio de Janeiro, composing a total of 1,879 vessels, described and analyzed the role of the environment on the spatial distribution and characterization. Data analysis showed that although environmental characteristics have formed distinct groups among physiographic compartments, these did not correspond to differences between fleets, which suggest that the environment is not the sole determinant of the type of vessel. Other factors that affect are historical and socioeconomic aspects. The absence of policies to stimulate the construction and modernization of vessels allows that the Rio de Janeiro’s fleet is currently described as old and obsolete, when compared to other coastal fleets in the Southeast and South of Brazil.
- Dec 2013
Major difficulties in studies monitoring or evaluating general environmental conditions are the intraspecific differences in population descriptors, such as the growth and reproductive period among different localities. The identification of feasible candidates for sentinel species requires basic information on these population parameters. Attention is drawn to the potential of the catfish Genidens genidens as a sentinel species for Brazilian estuarine environments, based on its compliance with a set of population descriptors and characteristics along a latitudinal gradient, and by providing new data from Guanabara Bay, one of the most important estuarine systems on the Brazilian coast. Populations of G. genidens along the southern and southeastern Brazilian coast vary little, showing a similar reproductive period and shape of the length–weight relationship among localities. This catfish is abundant, easy to catch, economically important, tolerant of environmental variations and human impacts, does not migrate, and can be found in reference localities, fulfilling the majority of the requirements for a sentinel species.
The present study investigated the reproductive biology of the pink shrimp Farfantepenaeus brasiliensis and Farfantepenaeus paulensis captured offshore and at two important fishing grounds, Guanabara Bay and Araruama Lagoon both on the south-eastern Brazil coast. The females’ size at first maturation was 37.90 mm of carapace length (CL) for F. brasiliensis and 41.95 mm of CL for F. paulensis. Both species presented continuous reproduction with two spawning peaks. For F. brasiliensis these peaks occurred during summer and winter and for F. paulensis during summer and autumn. The sex-ratio of the pink shrimp was favourable to the number of females which can be a strategy to guarantee the reproduction.
Guanabara Bay is a semi-closed tropical bay located in the center of metropolitan Rio de Janeiro. The ecological integrity of this system has a spatial gradient, with better environmental conditions near the mouth than in the inner bay. The objectives of this study were to monitor the exposure of the pond perch Diplectrum radiale (Perciformes; Serranidae) to metal pollution,using metallothionein as a specific biomarker, and to detect spatial differences in metal contamination in this large water body. The effects of biological factors (allometric condition factor, size, weight, and reproductive stage) and spatial variations on MT levels were also investigated among sampling sites. The results revealed intraspecific sources of variation influencing MT expression. Therefore, it was not possible to use MT as a sensitive biomarker to distinguish heavy metal pollution among sites within this bay. The spatial heterogeneity of metal bioavailability and the probable mobility of individual fish contributed to those findings. However, the pond perch can still be considered a good target organism to evaluate the effects of metal contamination through comparison with other estuarine ecosystems on the Brazilian coast.
The present study analysed the reproductive biology of Callinectes danae and Callinectes ornatus, which are captured as by-catch from pink-shrimp trawling in Guanabara Bay. The size at gonadal maturity was 79.9 mm and 67.4 mm respectively, for C. danae and C. ornatus. The pattern of reproduction was continuous for both species; however, the gonadosomatic index analyses showed seasonal and alternating reproductive peaks in the bay. While C. danae showed reproductive peaks in the autumn and in the winter, C. ornatus showed an apparent reproductive peak in the summer and probably another in the spring. The sex-ratio of C. danae was significantly skewed in favour of females (3.0:1). However, in C. ornatus, males predominated (1.2:1). This reproductive pattern indicated that possibly the females of C. danae return to the estuary after spawning where trawling takes place, while ovigerous females of C. ornatus migrate to adjacent coastal areas around the bay.
- Dec 2011
Half of the 14 LWR presented in this paper are unavailable in the FishBase website (Froese and Pauly, 2010), considered one of the main worldwide repositories for LWR equations: spotback skate, Atlantoraja castelnaui, Dasyatis hypostigma, spade sand skate, Psammobatis rutrum, R. horkelii and Z. brevirostris. The relationships for R. lalandii and P. lentiginosa were not in the database but were published in population studies conducted by Andrade et al. (2007) and Perier et al. (2010), respectively. This attests to the originality of this information and illustrates the need for more efforts directed towards calculating these parameters for elasmobranch species.
Dredging and dredge-spoil disposal are among the major problems in coastal management. Many of the scientific contributions concerning the impacts of this practice are based on the study of sessile organisms and subtropical environments. We evaluated changes in the composition and abundance of a fish assemblage resulting from dredging and sediment disposal at the mouth and in the adjacent waters of the Caravelas River on the north-eastern coast of Brazil. Samples were collected in two directly impacted and three adjacent areas. Differences among stations were not significant, but the dredged site had the least diverse station, as expected. The stations farthest from the directly impacted areas apparently were not influenced by the coastal work, thus suggesting localised effects. The contribution of the present study is particularly important because of the study area's proximity to others that have high conservation value such as mangrove forests and coral reefs, and the relevance of the subject given the continuing dredging activity.
- Oct 2011
The effects of mechanical stress caused by trawling, handling, air exposure, and discarding during fishing processes can cause irreversible damage to many bycatch organisms. The objective of this work was to evaluate quali-quantitatively the physical damage (loss of limbs) and differential survival among the portunid swimming crabs Callinectes danae Smith, 1869, Callinectes ornatus Ordway, 1863, and Achelous spinimanus (Latreille, 1819) in the pink shrimp trawling fishery in Guanabara Bay, Brazil. Physical damage was quantified by the incidence of lesions for each species in the following categories: male and female; juvenile and adult; and moulting and non-moulting organisms. The percentage of survivors was obtained through a 24-hour experiment in three consecutive days. The most frequently damaged species was C. danae; 58.9% of this species was observed to be injured. C. ornatus and A. spinimanus presented similar injury frequencies with injuries observed, respectively, in 44.3% and 43.5% of individuals of these species. The Chi-square value for male vs. female; juvenile vs. adult; and moulting vs. non-moulting organisms of each species did not exhibit significant differences except for adults and juveniles of C. danae. The most common type of damage observed among the species was the loss of chelipeds and/or pereiopods. Variance analysis did not detect significant differences in the survival of the various species at the different times of the experiment. The three species presented high survival percentages in all treatments, and live individuals of all species likely show similar recovery rates from trawling stress when returned to the sea.
- Jul 2011
Five liver samples of two different ray species (Gymnura altavela and Zapteryx brevirostris) off the coast of Rio de Janeiro, Brazil, were analyzed for their pollution with anthropogenic and naturally occurring organohalogen compounds.
The samples were extracted with accelerated solvent extraction, and after a clean-up procedure, organohalogen compounds were separated by a modified group separation on activated silica. Subsequent analyses were done by targeted and non-targeted gas chromatography-mass spectrometry in the electron capture negative ion mode.
"Classic" organohalogen compounds such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and technical 1,1,1-trichloro-2,2-di(4-chlorophenyl)ethane (DDT) were detected and quantified. PCBs generally exceeded the parts per million level and represented up to 90% of the total contamination of the ray livers. High concentrations were also detected for p,p'-DDE. Non-targeted full scan investigations lead to the detection of an abundant trichlorinated compound which was identified as a new DDT metabolite in biota. Different PBDE congeners and several halogenated natural products were quantified as well. In addition, polychlorinated terphenyls were identified and analyzed in the two species. Moreover, both ray species showed different fatty acid patterns and stable carbon isotope signatures.
The two ray species showed high concentrations of organohalogen compounds in their liver tissue. Varied δ (13)C values by up to 3.1‰ indicated that the two ray species were living in different habitats.
Guanabara Bay forms an estuarine ecosystem that is degraded on account of the action of several contamination sources. Despite this, it maintains an important fishery production that is mostly composed by Callinectes danae and Callinectes ornatus swimming crabs. Thirty-three trawlings were conducted from August 2002 to September 2003 in different locations in this bay, as well as visits to the Z-8 fishery colony, and cruises with fishermen. A total of 2,275 specimens were captured, of which 1,445 were C. ornatus and 830 C. danae. Their largest captures occurred in summer, being C. ornatus the most captured species
during the season. Continuous reproductive pattern was only verified for C. danae. Capture of adult individuals was higher than that of juveniles for both species and sexes. The sex ratios obtained for C. ornatus and C. danae were significantly different from the expected 1:1. Growth in weight showed a very similar pattern for both species. The fishery recruitment to Guanabara Bay`s trawling fleet started in autumn for C. danae (35.00 mm individuals) and in spring for C. ornatus (30.00 mm individuals).
A total of 2.702 skipjack tunas, Katsuwonus pelamis, were sampled from pole-and-line fishing vessel landings in Niterói harbor (Rio de Janeiro State), between January and December 2007. Furcal length (Lf) ranged from 40.1 to 85.6 cm and total weight (Wt) from 1.0 (1st and 2nd trimesters) to 11.3 kg (2nd trimester). Highest length and weight means were registered for the 4th trimester (61.4 cm and 4.9 kg,
respectively) and the lowest in the 1st trimester (57.2 cm and 3.1kg). The relationship between
furcal length and total weight, considering grouped sexes, was: TW= 3.817 x 10-6Lf3.3773 (n=2026; r2= 0.8716). Mean condition factor (K) ranged from 0.0062, in the 3rd trimester, to 0.0221 in the 2nd. Highest catches were observed from summer until the beginning of autumn, which were mainly composed of fishes older than three years old. In 2007 landings of tuna and tuna-like species, by the pole-and-line fleet, at Rio de Janeiro state were about 4,484 t, being 3,982 t of skipjack tuna and 502 t of the other species, as well as,
yellowfin tuna (Thunnus albacares), blackfin tuna, (Thunnus atlanticus), bigeye tuna (T. obesus),
albacore (T. alalunga), frigate tuna (Auxis thazard), little tuna (Euthynnus alletteratus), common dolphinfish (Coryphaena hippurus), and horse-eye jack (Caranx sp). From 2005 to 2007, the size of local fleet did not change, with 14 vessels. In 2007, these boats had a mean total length of 24.6 m and 112,8 gross tonnage.
Callinectes danae and Callinectes ornatus are two Portunidae crabs which are an important portion of the fishing products of Guanabara Bay, but are being discarded by shrimp trawlers along the Brazilian coast. Instantaneous mortality rates Z, M, F and the exploitation rates E for both species and for both sexes were estimated. Total mortality (Z) was estimated by length-converted catch curves and natural mortality (M) was based on life history analysis where K and t0 were parameters of the von Bertalanffy growth function. Fishing mortality rates presented low values of F for males of C. danae and C. ornatus (0.27 and 0.80), but not for the females (3.29 and 16.27). These females exhibited high values of fishing mortality and elevated exploitation rates (0.64 and 0.90). These high values may be a result of intense trawling in the region and/or the migration activity of these species to other coastal areas during the reproductive period, overestimating fishing mortality.
- Jun 2009
Along the Brazilian coast, Callinectes danae and Callinectes ornatus are very important species, both commercially and ecologically. The fishing pressure and the social and economic importance of the group justify the need for specific detailed information concerning the reproduction of each representative for the development of management actions. Histological procedures associated with a chromatic colour scale have pointed out four ovarian developmental stages to be distinguished in both species, classified as: stage-I (immature), stage-II (developing), stage-III (ripe), and stage-IV (spent). The presence of oocytes-I and oocytes-II in the stages "ripe" and "spent" indicates that spawning takes place with at least two lots of mature oocytes for both species. However, the possibility of a single spawning during critical situations of stress cannot be rejected.
Portuguese
Ao largo da costa brasileira, Callinectes danae e Callinectes ornatus são espécies importantes comercialmente e ecologicamente. A pressão por pesca somada a importância social e econômica do grupo justifica a necessidade de informações específicas detalhadas a respeito da reprodução de cada um para desenvolvimento de ações de manejo. Procedimentos histológicos associados a uma escala cromática de cores distinguiu quatro estágios de desenvolvimento gonadal, classificados como: estágio-I (imaturo), estágio-II (desenvolvimento), estágio-III (maduro) e estágio-IV (desovado). A presença de ovócitos-I e ovócitos-II nos estágios maduro e desovado indica uma desova em pelo menos dois lotes de ovócitos maduros para ambas as espécies. No entanto, a possibilidade de uma desova simples em situações críticas de estresse não deve ser rejeitada.
- Apr 2009
- DIAGNÓSTICO DA CADEIA PRODUTIVA DA PESCA MARÍTIMA NO ESTADO DO RIO DE JANEIRO
O Estado do Rio de Janeiro possui 25 municípios costeiros e um total de 25 colônias de pescadores, além de inúmeras associações, cooperativas e outras instituições classistas representando os diferentes segmentos do setor. Sua costa Marinha, de 640 km, é a terceira mais extensa do País. Com a média de produção extrativa pesqueira Marinha anual de 62 mil toneladas, no período 2002-2006, coloca-se na terceira posição na lista dos maiores produtores de pescado do país e na primeira posição dentre os estados do Sudeste brasileiro. Estima-se que, em termos de preço de primeira comercialização, a atividade pesqueira no Estado gere uma receita anual de aproximadamente 180 milhões de reais (Ibama, 2004a, 2004b, 2005a, 2007, 2008). A atividade pesqueira fluminense é variada, assim como os ecossistemas ao longo de sua costa. Entre a desembocadura do Rio Itabapoana, divisa norte com o Estado do Espírito Santo, e a Ponta de Trindade, na divisa sul com o Estado de São Paulo, situam-se diversas ilhas costeiras, baías, estuários, lagunas, praias arenosas e costões rochosos. Diariamente são lançados ao mar redes de arrasto e de cerco, menjoadas (tipo de rede de emalhe), linhas e anzóis para a captura de diversos peixes, moluscos e crustáceos. De acordo com o Censo Estrutural da Pesca Artesanal Marítima e Estuarina (Prozee, 2005) existem no estado fluminense cerca de 20 mil pescadores e 3.023 embarcações cadastradas. As maiores concentrações de pescadores encontram-se na Baía da Guanabara e Região dos Lagos. As localidades pesqueiras dos municípios de Magé, Rio de Janeiro, Niterói e São Gonçalo, às margens da Baía da Guanabara, destacam-se por possuírem 69% das embarcações cadastradas no estado. As localidades do Rio de Janeiro/Niterói, Cabo Frio e Angra dos Reis têm grande importância em termos de produção pesqueira desembarcada (Prozee, 2005).
- Apr 2009
- Diagnóstico da cadeia produtiva da pesca marítima no Estado do Rio de Janeiro
O ato de pescar, apesar de ser realizado no mar, tem seu maior ou menor sucesso dependendo diretamente do suporte logístico oferecido em terra. Como é muito comum em todas as etapas da cadeia produtiva do pescado, muito dessa estrutura de apoio é informal e desconhecida de boa parte do poder público. Essa realidade dificulta enormemente qualquer política de desenvolvimento ou gerenciamento do setor pesqueiro, como a importante atividade econômica que é. Ao longo de toda a costa do Estado do Rio de Janeiro, as estruturas - que fazem parte do apoio à atividade do setor pesqueiro - estão sob diversas formas de pressão, como a imobiliária e a de geração de energia (petróleo e gás), que tomam espaços que anteriormente eram ocupados pelo setor, dificultando ou tornando mais custoso o acesso ao mar. Essa queda na oferta de apoio logístico em terra encarece as operações de armação, descarga e manutenção das embarcações de pesca, diminuindo a qualidade do pescado que chega ao mercado consumidor, além de geralmente torná-lo mais caro. Um ponto importante de ser observado é a fragmentação das entidades de classe tradicionais, as colônias de pesca, com o surgimento de inúmeras capatazias, associações, cooperativas e outras organizações classistas. Isso vem acontecendo por causa do enfraquecimento das colônias e de suas lideranças ou pela inexistência de representatividade em suas
regiões. Divergências políticas também são fatores responsáveis por essa diversidade de entidades, que dividem seus participantes e em alguns casos inviabilizam simplesmente sua existência. Ainda a falta de vinculação com entidades agregadoras, tais como federações, promove a falta de unicidade. O objetivo deste capítulo é realizar um levantamento de campo da infraestrutura utilizada como apoio à atividade
pesqueira industrial no Estado do Rio de Janeiro. Todos os municípios costeiros do estado foram amostrados e as instalações de apoio identificadas, visitadas, georreferenciadas e tiveram um questionário preenchido. As informações contidas neste levantamento foram condensadas em tabelas e gráficos e apresentam um panorama real da infraestrutura disponível.
- Apr 2009
- Diagnóstico da cadeia produtiva da pesca marítima no Estado do Rio de Janeiro
- Apr 2009
- Diagnóstico da cadeia produtiva da pesca marítima no Estado do Rio de Janeiro
A pesca industrial é uma importante atividade econômica para o Estado do Rio de Janeiro. A liderança do estado no panorama da pesca nacional é um passado recente que se torna cada vez mais distante, em função da degradação ambiental do nosso litoral, políticas publicas equivocadas, declínio das pescarias tradicionais, tecnologias obsoletas, informalidade do setor empresarial e descaso das autoridades governamentais. Entretanto, essa perspectiva pode ser mudada, pois as características geográficas privilegiadas do Rio de Janeiro e o mercado consumidor local receptivo suportam essa transformação. A inversão da tendência de declínio pode ser realizada com uma serie de medidas factíveis de serem implementadas em um espaço de tempo não muito longo. Somente com novas e urgentes diretrizes nas políticas públicas do estado e a efetiva participação do empresariado da pesca esse quadro será possível.
The whitemouth croaker Micropogonias furnieri is the most common species of Sciaenidae in Guanabara Bay, southeastern coast of Brazil. Data from monthly trawls taken from a shrimp boat between May 2003 and June 2005 showed that whitemouth croakers are regularly present yearround; the catch was entirely composed of juveniles. The length-weight relationship for pooled sexes was represented by the equation Wt = 0.0053*Lt3.183. Significant seasonal differences in the condition factor were not observed (p>0.05). Regarding the morphometric characterization of this population stratum, most of the characters examined showed isometric growth, except for Pre-anal Distance, which showed positive allometry and Eye Diameter, which showed negative allometry. Morphometric aspects of the population in Guanabara Bay seem to be similar to those from coastal populations of southeastern Brazil (population I), which differ from populations on the south coast.
Twenty two Brazilian estuarine locations with published lists of their respective inhabiting fi sh species, were studied in preparing the present paper. They geographically varied from equatorial environments (the Amazonian estuary in Pará State) to subtropical envorironments (Arroi-Chuí estuary in Rio Grande do Sul State). A total of 304 demersal teleost species belonging to 83 families were listed to these systems. The following familes, in this order, were represented by a greater number of species: Sciaenidae, Gobiidae, Serranidae, Ariidae, Haemulidae, Gerreidae, Paralichthyidae and Syngnathidae. These species were grouped according to their life strategies as: estuarine opportunists (54.3%), freshwater fi sh (14.9%), estuarine-dependent fi sh (13.2%), estuarine-dwelling fi sh (9.9%), diadromous fi sh (2.6%) and fi sh with unknown life histrories (5.0%). Only 11 species were common to all examined estuarine localities and the estuarine-dwelling Gobionellus oceanicus (Gobiidae) presented the greatest range of different habitats. From comparison, it seems that with the geographical range of the different fi sh species depend heavily on their individual spatial heterogeneity and tolerance to salinity and not so much on their mode of life. A partir de levantamentos ictiofaunísticos disponíveis, foram selecionados 22 sistemas estuarinos ao longo da costa brasileira para o presente estudo. A extensão geográfi ca abrangeu desde ambientes equatoriais (estuário Amazônico � estado do Pará) até sub-tropicais (estuário do Arroio-Chuí � estado do Rio Grande do Sul). Um total de 304 espécies e 83 famílias de teleósteos demersais foram associadas a estes sistemas. As famílias Sciaenidae, Gobiidae, Serranidae, Ariidae, Haemulidae, Gerreidae, Paralichthyidae e Syngnathidae, nesta ordem, foram as mais representativas em número de espécies. De acordo com as estratégias de ocupação dos estuários, as espécies foram agrupadas em: estuarino-oportunistas (54,3%), aqüadulcícolas (14,9%), estuarinodependentes (13,2%), estuarino-residentes (9,9%) e diádromas (2,6%), além das espécies sem defi nição de suas estratégias de vida (5,0%). Apenas 11 espécies são comuns a todos os sistemas, sendo que o gobiídeo estuarinoresidente Gobionellus oceanicus encontra-se amplamente distribuído em todos os estuários. Observou-se que os padrões de distribuição das ictiocenoses ao longo da costa brasileira são mais associados à heterogeneidade espacial e tolerância à variação de salinidade do que às estratégias de vida das espécies.
- Jul 2008
The use of biological responses, biomarkers, measured at the
molecular level has been proposed as sensitive ‘early warning’
tools for biological effect measurement in environmental quality
assessment. Guanabara Bay is a heavily polluted, 384-km2
, eutrophic
water body, which receives inputs from untreated domestic
and industrial sewage from around 10,000 plants, two harbours,
shipyards and oil terminals. In this work we use a multibiomarker
approach in fish species to assess the impact of pollution in this
aquatic body with a complex pollution situation. The multibiomarker
approach involves a general biomarker of the health of individual
fish, the condition factor, and specific biomarkers of
contaminant exposure such as metallothionein, acetylcholinesterase
activity, Ethoxyresorufin-O-deethylase activity and bile polycyclic
aromatic hydrocarbons metabolites. The biological responses
chosen are those that would give information on the effect of
the main polluted activities of the river. Our results show that
the multibiomarker approach applied in the present study clearly
revealed differences in the health of fish among reference and
potentially contaminated sites and also characterized the effects
of human activities in this water body. The overall results obtained
from this investigation could be very useful in identifying the
source of chemicals released and their toxic repercussion on the
aquatic ecosystem. There is also a potential use of this monitoring
approach for defining pollution control policies and conservation
strategies.
- Feb 2008
Throughout 1 year, from October 2003 to September 2004, 88 visits to the landing site of a small urban fishery (APREBAN) in Rio de Janeiro city were conducted and 816 specimens of Rhizoprionodon lalandii were analysed. The sample, mostly females, was composed of two cohorts: young-of-the-year were abundant in spring and summer and adults predominated in autumn and winter. Gravid females were most abundant from April to June, whereas post-partum females composed most of the catch in August to September. Adult males were present all year although were more abundant between February and July. No neonates were captured during the study and most embryos collected measured slightly below the reported total length (LT) at time of birth (L0) for the species, suggesting that parturition may occur slightly outside the main fishing grounds or that neonates were not captured in commercial gillnets set at this time of the year. The mean LT at maturity (LT50) for males was 578 mm and females matured between 620 and 660 mm, although a precise estimate of LT50 for females could not be determined. The total length (LT) and total mass (MT) relationship was calculated for both sexes and showed no significant differences. The mean condition factor increased steadily from February to July followed by a steep decrease in values relative to females in August and September, suggesting a pupping season. The present study area can be classified as a coastal juvenile habitat and a probable mating ground for R. lalandii.
The diet of the monkfish Lophius gastrophysus is described based on the analysis of stomach contents, for the south-western Atlantic from samples landed in the fishing port of Niteroi, Rio de Janeiro state, Brazil, from April 2004 to March 2006. Feeding intensity, measured as the presence or absence of contents in stomachs, and differences in the items' composition were analysed by sex, size-class and season. High feeding intensity predominated for females >32 cm and for males <31 cm. There was no seasonal pattern in the occurrence of full or empty stomachs. The most important category in the diet was fish with 25 identified species. Dactylopterus volitans showed the highest alimentary index value, mainly because of the feeding of juvenile monkfish. The second most important category was Mollusca, represented mainly by squid. No relationships between predator- and prey-lengths and weights were observed; but there was a tendency to consume light and small prey independently of the size of the monkfish.
Small-scale fisheries are the sole source of income for millions of people around the world and operate mainly in coastal waters. This zone is used by many elasmobranch species as feeding, mating, pupping and/or nursery areas. APREBAN is a group of small-scale urban fishermen that explores the coast of Rio de Janeiro (RJ), working mainly about the 30-meter isobath, using gillnets of variable dimensions and mesh sizes. During two years of monitoring landings, 1,617 elasmobranchs of 27 species were registered, including nine threatened with extinction. Different stages of maturity were observed, including neonates and gravid or post-partum females of eight, in addition to Squatina spp.. The study area has shown important ecological relevance for elasmobranchs, especially Rhizoprionodon spp., Sphyrna spp., Squatina spp., Rhinobatos horkelii and Carcharhinus spp. We recommend a more extensive monitoring of the landings along Rio de Janeiro State in order to better characterize coastal habitat use by Elasmobranchs and their interactions with smallscale fisheries.
BIOLOGY AND ECOLOGY OF ANGLERFISHES OF THE GENUS LOPHIUS (LOPHIIDAE, LOPHIIFORMES) WITH EMPHASIS IN LOPHIUS GASTROPHYSUS MIRANDA-RIBEIRO, 1915: CURRENT STATUS. We reviewed available information on seven species of anglerfishes of the genus Lophius, all of them economically important. Geographically, anglerfishes are distributed on the continental shelf and slope of the Atlantic, Western Pacific, and Indian oceans. Many of the studies refer to two species of the north- eastern Atlantic, the black-bellied angler Lophius budegassa and the angler Lophius piscatorius. Lophiids have received their common name because of the characteristic way that they attract prey to their wide mouth, by moving the illicium (the modified first ray of the dorsal fin), located at the tip of the snout. Recent underwater
One reversed Citharichthys macrops Dresel, 1885 and two ambicolored Paralichthys isosceles Jordan, 1891 specimens were caught in Guanabara Bay and Ilha Grande Bay, respectively. The prior is the first record of reversal for the genus in the Southwestern Atlantic Ocean and the first for the species in the world, whereas the latter are the first record for the species in Brazil. In both cases, the abnormal specimens are meristically and morphometrically similar to the normal individuals.
The pink shrimp trawling fishery (Farfantepenaeus brasiliensis and F. paulensis) in the Ubatuba region acts intensely on the populations of some benthic species. The impact of fisheries on herbenthic community is unknown. Samples of herbenthic community were obtained monthly from July/1995 to August/1996. The last haul from a commercial trawler operating on the northern coast of São Paulo State and the southern coast of Rio de Janeiro State was preserved (from being discarded) and identified at the species level. 29 species of crustaceans were found, but only Hepatus pudibundus, Callinectes ornatus, Dardanus insignis, Libinia spinosa, Sicyonia tipica, Portunus spinimanus, Portunus spinicarpus, and Persephona mediterranea had high occurrence and frequency values. Such species were the main crustacean itens in the bycatch of the pink shrimp fisheries in Ubatuba for the period of study. The total bycatch was about 1502 tons, composed by 119 tons of incidental catch and 1383 tons of discarded catch. Considering the study area, these values were quite high demonstrating that some species may have been overfished.
The need for this study appeared during a CEPSUL/IBAMA meeting. The problem at hand was
that the fishing industry was substituting the traditional gears by the portable liftnet, that presented
higher capture efficiency, but low selectivity, causing overfishing and reduction of the disembarked
length classes. The aim of the study was to characterize the gear used in the States of Rio de Janeiro
and Espirito Santo. The portable liftnet was described in terms of its dimensions, materials and
mode of operation. Two models directed towards the capture of Balistes capriscus and a third
towards Aluterus monoceros were identified. It was not clear upon which population stratum was
the gear acting. Therefore, this information was complemented by the fishermen, who affirmed
that the device presented greater capture of small individuals. The results were discussed with the
fishermen who operated with portable liftnet and the general consensus was that technological
modifications in the gear would not be respected by the industry and that the alternative would
be its prohibition. With the fishermen´s approval, the large liftnet was considered inadequate and
the continued prohibition of this gear is recommended.
A total of 13.927 individuals of Lophius gastrophysus landed by the shrimp fishing fleet at a fishing port of Niteroi, state of Rio de Janeiro, were measured. The fish were landed separately in two commercial categories: small (individuals less than 1 kg) and large (over 1 kg). Two sampling periods were distinguished: from March 2004 to February 2005 (first period) and from March 2005 to February 2006 (second period). The length-class structure was completely dominated by small-sized individuals, even in the “large” category, over the entire sampling period, and showed the large catch of young individuals. It is concluded that this fleet impacts heavily on the stock of L. gastrophysus, because it acts basically on the population stratum of juveniles, because of the poor selectivity of the trawl nets used and the area of the continental shelf where the fleet fishes. We recommend the implementation of measures to reduce this catch, so as not to compromise the development of a sustainable fishery for L. gastrophysus. A total of 13.927 individuals of Lophius gastrophysus landed by the shrimp fishing fleet at a fishing port of Niteroi, state of Rio de Janeiro, were measured. The fish were landed separately in two commercial categories: small (individuals less than 1 kg) and large (over 1 kg). Two sampling periods were distinguished: from March 2004 to February 2005 (first period) and from March 2005 to February 2006 (second period). The length-class structure was completely dominated by small-sized individuals, even in the “large” category, over the entire sampling period, and showed the large catch of young individuals. It is concluded that this fleet impacts heavily on the stock of L. gastrophysus, because it acts basically on the population stratum of juveniles, because of the poor selectivity of the trawl nets used and the area of the continental shelf where the fleet fishes. We recommend the implementation of measures to reduce this catch, so as not to compromise the development of a sustainable fishery for L. gastrophysus.
- Nov 2006
The main shrimp fishery in Patos Lagoon, southern Brazil, is conducted with stow nets and light baiting. The target species is the juvenile pink shrimp, Farfantepenaeus paulensis; the largest components of the by-catch are the blue crab, Callinectes sapidus, and the white croaker, Micropogonias furnieri. In this study, we calculated the biometric relationships for these species, and we tested a by-catch reduction device that consisted of a grid placed over the opening of the net. The performance of grids with spaces of 25, 30 and 35 mm between the bars was assessed. The grid with the smallest spacing was the most efficient in reducing by-catch. This device excludes mature individuals from the net, with negligible loss in shrimp production.
Trawling for pink shrimp (Farfantepenaeus brasiliensis and F. paulensis) catches also large quantities of fish, mostly bony fish, which are discarded, as they have no commercial value. Their composition and abundance were studied in an area that corresponded to the southeastern coastline of Brazil. Ninety one species were registered. Incidental fishing affected mainly small individuals and occured throughout the year. The year round rate of bony fish to shrimp catches was 10,5:1,0. Three assemblages of bony fishes could be identified, influenced by the seasonal variation of the water masses, the predominant group being associated with the Coastal Water, another with the penetration of colder waters onto the platform (SACW) and a third group of a more homogenous distribution. The most critical period identified for the bycatch capture was the beginning of the winter, which was due to the overlapping of fish assemblages and the peak of fishing recruitment.
Length-weight relationship (LWR) parameters of 51 species of demersal fish caught as by-catch by shrimp fishery trawl, in the southeastern coast of Brazil are reported. This is the first compilation of LWR for most of the cited species in Brazil, and indicates a positive allometric tendency for b in the sampled fish community.
In the Ubatuba city, located in the northern coast of São Paulo state, during the period 1995-1996 the fishery was considered an important economical activity, that was practiced with the aid of a fleet composed by 162 boats. The activity was centralized in the trawl fishery (62%), performed with small boats and low investments. The results of the present study permit to conclud that the increase of the fishing sector neads the stimulation of the development of semi-industrial fishery, which is attained through the training of the fishermen, and so, promoting the improvement of the quality of the product.
Population biology of Orthopristis ruber (TELEOSTEI, HAEMULIDAE), caught as pink-shrimp by-catch of off southern Brazil. Trawl fishing for pink shrimp catches large quantities of by -catch fish, discarded due to their having no commercial value. This contribution studies the biology of the Atlantic midshipman Orthopristis ruber. The last haul from a commercial trawler, operating on the northern coast of São Paulo State and the southern coast of Rio de Janeiro State, was preserved, from being discarded. It was observed that this fishery affects the population that is influenced by the seasonal variation of the water masses. Parameters were estimated: L∞ = 41.0 cm, k = 0.350 year -1 , Rn = 443 (10 -3 ), Z = 2.46, M = 0.73, F = 1.73, S = 8.55 %, E = 0.70 year -1 and Lm = 15.64 cm. Considering the intensive activity of the shrimp trawl fleet operating in this area, the deleterious action of trawling is considered as of high impact. The stock management measures applied for pink shrimp are without effect regarding O. ruber, which has its spawning period before the closed season and its recruitment peak after it. The results show overfishing and the need to apply measures to reduce trawling action, such as adequate policies, introduction of selectivity devices and the creation of exclusion zones for trawl fishing.
Trawl fishing for pink shrimp (Fmfantepenaeus brasiliensis and F. paulensis) catches large quantities of by-cateh fish, discarded due to their having no commercial value. As these species have rarely been studied, the impact of fisheries on these populations is not known. This contribution studies the biology of a species of no commercial value, the Atlantic midshipman Porichthys porosissimus. The last haul fToma commercial trawler, operating on the northern coast of São Paulo State and the southern coast of Rio de Janeiro State, was preserved (from being discarded) and identified at the species leveI. It was observed that this fishery affects the juvenile population which is intluenced by the seasonal variation of the water masses. Growth parameters were estimated: Lx = 37.0 em, K = 0.285 year,l. Instantaneous mortality coefficients were estimated: Z=2.14. M=0.63, F= 1.51, S= 11.8 and E=0.71. Considering the intensive activity ofthe shrimp trawl tleet operating in this area, the deleterious action of trawling is considered as of high impact. The stock management measures applied for pink shrimp are without effect regarding P. porosissimus, which has its spawning period before the c\\osed season and its recruitment peak after it. The resu1ts show overfishing and the need to apply measures to reduce trawling action, such as adequate policies, introduction of selectivity devices and the creation of exc\\usion zones for trawl fishing. .
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