Feeding activity of the cayenne pompano Trachinotus cayennensis (Cuvier 1832) (Perciformes, Carangidae) in estuaries on the western coast of the state of Maranhão, Brazil / Atividade alimentar do pampo Trachinotus cayennensis (Cuvier 1832) (Perciformes, Carangidae) em estuários do litoral ocidental do Estado do Maranhão, Brasil

The present paper addresses the feeding activity of Trachinotus cayennensis, collected in Lençóis Bay (1°18S 1°19S; 44°51W 44°53W) on the western coast of the state of Maranhão, Brazil. Sampling was conducted between June 2012 and June 2013 using driftnets with stretch mesh sizes from 95 to 100 mm. A total of 205 individuals (114 females and 91 males) were analyzed. Statistically significant differences in the sex ratio were found in June, September and December 2012. Food items were analyzed based on frequency of occurrence and volumetric method, with the subsequent calculation of the alimentary importance index. Three size groups were defined to determine possible ontogenetic changes in eating habits based on the size range of the individuals collected: I ( 29 cm), II (29.1 to 37.0) and III ( 37.1). Eleven food item categories were identified: mollusks, polychaetes, crustaceans, nematodes, insects, algae, bryozoans, ophiuroids, fishes, vegetal matter and sediments. The variety of items in the diet of T. cayennensis indicates considerable feeding plasticity and opportunistic behavior. Seasonal variations influenced the feeding pattern of the species, with greater feeding activity in the dry season. The considerable availability of resources in estuarine habitats of the western coast of Maranhão constitutes another factor that influences the feeding behavior of this species.(AU)

Atividade alimentar do pampo Trachinotus cayennensis (Cuvier 1832) (Perciformes, Carangidae) em estuários na costa ocidental do Maranhão, Brasil. O presente trabalho descreve a atividade alimentar do Trachinotus cayennensis , coletado na Baía de Lençóis (1°18S 1°19S; 44°51W 44°53W) na costa oeste do Maranhão. Amostragens foram realizadas entre junho de 2012 e junho de 2013, utilizando redes de emalhar à deriva com tamanho de malha de 95 a 100 mm. Foram analisados 205 indivíduos (114 fêmeas e 91 machos). Encontraram-se diferenças estatisticamente significativas na proporção sexual nos meses de junho, setembro e dezembro de 2012. Os itens alimentares foram analisados com base na frequência de ocorrência e utilizando o método volumétrico, com o subsequente cálculo do índice de importância alimentar. Três grupos de tamanho foram definidos para determinar possíveis mudanças ontogenéticas nos hábitos alimentares com base na faixa de tamanho dos indivíduos coletados: I ( 29 cm), II (29,1 a 37,0) e III ( 37,1). Foram identificadas 11 categorias de alimentos: moluscos, poliquetas, crustáceos, nematoides, insetos, algas, briozoários, ophiuro, peixes, matéria vegetal e sedimentos. A variedade de itens na dieta de T. cayennensis indica uma plasticidade alimentar considerável e um comportamento oportunista. As variações sazonais influenciaram o padrão alimentar da espécie, com maior atividade de alimentação na estação seca. A considerável disponibilidade de recursos nos habitats estuarinos da costa oeste do Maranhão constitui outro fator que exerce influência sobre o comportamento alimentar desta espécie.(AU)

Feeding activity of the cayenne pompano Trachinotus cayennensis (Cuvier 1832) (Perciformes, Carangidae) in estuaries on the western coast of the state of Maranhão, Brazil

Abstract The present paper addresses the feeding activity of Trachinotus cayennensis, collected in Lençóis Bay (1°18S 1°19S; 44°51W 44°53W) on the western coast of the state of Maranhão, Brazil. Sampling was conducted between June 2012 and June 2013 using driftnets with stretch mesh sizes from 95 to 100 mm. A total of 205 individuals (114 females and 91 males) were analyzed. Statistically significant differences in the sex ratio were found in June, September and December 2012. Food items were analyzed based on frequency of occurrence and volumetric method, with the subsequent calculation of the alimentary importance index. Three size groups were defined to determine possible ontogenetic changes in eating habits based on the size range of the individuals collected: I ( 29 cm), II (29.1 to 37.0) and III ( 37.1). Eleven food item categories were identified: mollusks, polychaetes, crustaceans, nematodes, insects, algae, bryozoans, ophiuroids, fishes, vegetal matter and sediments. The variety of items in the diet of T. cayennensis indicates considerable feeding plasticity and opportunistic behavior. Seasonal variations influenced the feeding pattern of the species, with greater feeding activity in the dry season. The considerable availability of resources in estuarine habitats of the western coast of Maranhão constitutes another factor that influences the feeding behavior of this species.

Resumo Atividade alimentar do pampo Trachinotus cayennensis (Cuvier 1832) (Perciformes, Carangidae) em estuários na costa ocidental do Maranhão, Brasil. O presente trabalho descreve a atividade alimentar do Trachinotus cayennensis , coletado na Baía de Lençóis (1°18S 1°19S; 44°51W 44°53W) na costa oeste do Maranhão. Amostragens foram realizadas entre junho de 2012 e junho de 2013, utilizando redes de emalhar à deriva com tamanho de malha de 95 a 100 mm. Foram analisados 205 indivíduos (114 fêmeas e 91 machos). Encontraram-se diferenças estatisticamente significativas na proporção sexual nos meses de junho, setembro e dezembro de 2012. Os itens alimentares foram analisados com base na frequência de ocorrência e utilizando o método volumétrico, com o subsequente cálculo do índice de importância alimentar. Três grupos de tamanho foram definidos para determinar possíveis mudanças ontogenéticas nos hábitos alimentares com base na faixa de tamanho dos indivíduos coletados: I ( 29 cm), II (29,1 a 37,0) e III ( 37,1). Foram identificadas 11 categorias de alimentos: moluscos, poliquetas, crustáceos, nematoides, insetos, algas, briozoários, ophiuro, peixes, matéria vegetal e sedimentos. A variedade de itens na dieta de T. cayennensis indica uma plasticidade alimentar considerável e um comportamento oportunista. As variações sazonais influenciaram o padrão alimentar da espécie, com maior atividade de alimentação na estação seca. A considerável disponibilidade de recursos nos habitats estuarinos da costa oeste do Maranhão constitui outro fator que exerce influência sobre o comportamento alimentar desta espécie.

Feeding activity of the cayenne pompano Trachinotus cayennensis (Cuvier 1832) (Perciformes, Carangidae) in estuaries on the western coast of the state of Maranhão, Brazil

Abstract The present paper addresses the feeding activity of Trachinotus cayennensis, collected in Lençóis Bay (1°18S 1°19S; 44°51W 44°53W) on the western coast of the state of Maranhão, Brazil. Sampling was conducted between June 2012 and June 2013 using driftnets with stretch mesh sizes from 95 to 100 mm. A total of 205 individuals (114 females and 91 males) were analyzed. Statistically significant differences in the sex ratio were found in June, September and December 2012. Food items were analyzed based on frequency of occurrence and volumetric method, with the subsequent calculation of the alimentary importance index. Three size groups were defined to determine possible ontogenetic changes in eating habits based on the size range of the individuals collected: I ( 29 cm), II (29.1 to 37.0) and III ( 37.1). Eleven food item categories were identified: mollusks, polychaetes, crustaceans, nematodes, insects, algae, bryozoans, ophiuroids, fishes, vegetal matter and sediments. The variety of items in the diet of T. cayennensis indicates considerable feeding plasticity and opportunistic behavior. Seasonal variations influenced the feeding pattern of the species, with greater feeding activity in the dry season. The considerable availability of resources in estuarine habitats of the western coast of Maranhão constitutes another factor that influences the feeding behavior of this species.

Resumo Atividade alimentar do pampo Trachinotus cayennensis (Cuvier 1832) (Perciformes, Carangidae) em estuários na costa ocidental do Maranhão, Brasil. O presente trabalho descreve a atividade alimentar do Trachinotus cayennensis , coletado na Baía de Lençóis (1°18S 1°19S; 44°51W 44°53W) na costa oeste do Maranhão. Amostragens foram realizadas entre junho de 2012 e junho de 2013, utilizando redes de emalhar à deriva com tamanho de malha de 95 a 100 mm. Foram analisados 205 indivíduos (114 fêmeas e 91 machos). Encontraram-se diferenças estatisticamente significativas na proporção sexual nos meses de junho, setembro e dezembro de 2012. Os itens alimentares foram analisados com base na frequência de ocorrência e utilizando o método volumétrico, com o subsequente cálculo do índice de importância alimentar. Três grupos de tamanho foram definidos para determinar possíveis mudanças ontogenéticas nos hábitos alimentares com base na faixa de tamanho dos indivíduos coletados: I ( 29 cm), II (29,1 a 37,0) e III ( 37,1). Foram identificadas 11 categorias de alimentos: moluscos, poliquetas, crustáceos, nematoides, insetos, algas, briozoários, ophiuro, peixes, matéria vegetal e sedimentos. A variedade de itens na dieta de T. cayennensis indica uma plasticidade alimentar considerável e um comportamento oportunista. As variações sazonais influenciaram o padrão alimentar da espécie, com maior atividade de alimentação na estação seca. A considerável disponibilidade de recursos nos habitats estuarinos da costa oeste do Maranhão constitui outro fator que exerce influência sobre o comportamento alimentar desta espécie.

The non-indigenous bryozoan Triphyllozoon (Cheilostomata: Phidoloporidae) in the Atlantic: morphology and dispersion on the Brazilian coast

Bryozoans constitute an important component of marine-fouling communities of anthropogenic substrata. Many species have been reported as exotic or widespread around the world, typically in ports and harbors of non-polar regions. Here we present the first record of a species of the bryozoan Triphyllozoon in the Atlantic Ocean. Triphyllozoon arcuatum (MacGillivray, 1889), described originally from Australia, is reported herein from natural substrata in Singapore and natural and artificial substrata in Brazil. Although easily recognizable, the species has not been previously reported from anywhere else in the Atlantic. In the latter instance, the species was collected during monitoring of the invasive scleractinian corals Tubastraea spp. on an oil platform originally from Singapore and now located at Todos os Santos Bay, northeastern Brazil. Colonies of T. arcuatum were also found associated with three species of sponges, giving evidence that it is also growing in the natural environment. Todos os Santos Bay is characterized by intense commercial shipping traffic and oil exploration and the finding of T. arcuatum on an oil platform provides strong evidence that it represents a non-indigenous species in the Atlantic. Owing to the possible impact of T. arcuatum in Brazil, further studies and monitoring of its bioinvasion are recommended.

The non-indigenous bryozoan Triphyllozoon (Cheilostomata: Phidoloporidae) in the Atlantic: morphology and dispersion on the Brazilian coast

Bryozoans constitute an important component of marine-fouling communities of anthropogenic substrata. Many species have been reported as exotic or widespread around the world, typically in ports and harbors of non-polar regions. Here we present the first record of a species of the bryozoan Triphyllozoon in the Atlantic Ocean. Triphyllozoon arcuatum (MacGillivray, 1889), described originally from Australia, is reported herein from natural substrata in Singapore and natural and artificial substrata in Brazil. Although easily recognizable, the species has not been previously reported from anywhere else in the Atlantic. In the latter instance, the species was collected during monitoring of the invasive scleractinian corals Tubastraea spp. on an oil platform originally from Singapore and now located at Todos os Santos Bay, northeastern Brazil. Colonies of T. arcuatum were also found associated with three species of sponges, giving evidence that it is also growing in the natural environment. Todos os Santos Bay is characterized by intense commercial shipping traffic and oil exploration and the finding of T. arcuatum on an oil platform provides strong evidence that it represents a non-indigenous species in the Atlantic. Owing to the possible impact of T. arcuatum in Brazil, further studies and monitoring of its bioinvasion are recommended.(AU)

The seasonal diet of Aequidens tetramerus (Cichlidae) in a small forest stream in the Machado River basin, Rondônia, Brazil / Dieta sazonal de Aequidens tetramerus (Cichlidae) em um igarapé da bacia do rio Machado, Rondônia, Brasil

Trophic relationships in fish communities are affected by the availability of resources, which in turn is affected by spatial and temporal variations throughout the year. The aims of this study were to characterize the diet of A. tetramerus in a streamlet in the north of Brazil and compare its composition in different hydrological seasons (wet and dry seasons). Collections were performed every two months from October 2011 to September 2012 with the aid of seine nets, hand net and fishing traps in the streamlet located in the Machado River drainage basin in the Rondônia state. Most of the specimens collected were quite small (<40 mm) and had empty stomachs. Our results showed that A. tetramerus feeds on a wide variety of items of plant origin, such as algae, seeds and leaves, as well as items of animal origin, including bryozoans, crustaceans, fish scales, terrestrial insects and detritus. The data also indicated higher consumption of aquatic insects than other food items, suggesting a primarily insect-based diet. Items of plant and allochthonous origin were consumed more in the wet season than in the dry season, but there were no seasonal differences in the consumption of animal and autochthonous items.(AU)

Relações tróficas das comunidades de peixes são afetadas por variações espaciais e temporais, que alteraram a disponibilidade de recursos ao longo do ano. Os objetivos deste estudo foram caracterizar a dieta de A. tetramerus no igarapé estudado, bem como comparar se a composição dos itens da dieta desta espécie dependem da estação hidrológica (período chuvoso e seco). As coletas foram realizadas bimestralmente, de Outubro de 2011 a Setembro de 2012, com auxílio de picaré, puçá e covos em um igarapé localizado na bacia do rio Machado no estado de Rondônia. A maioria dos espécimes eram pequenos (<40 mm) e tinham estômago vazio. Observou-se que A. tetramerus se alimenta de uma grande variedade de itens de origem vegetal, como algas, sementes e folhas; e de itens de origem animal como: briozoários, crustáceos, escamas, insetos terrestres e detritos. Constatou-se que há maior consumo de insetos aquáticos, o que sugere uma dieta insetívora. Itens de origem vegetal e alóctones foram mais consumidos na estação chuvosa do que na estação seca. Não houve diferença na composição da dieta dos peixes entre as estações de seca e chuva.(AU)

The seasonal diet of Aequidens tetramerus (Cichlidae) in a small forest stream in the Machado River basin, Rondônia, Brazil / Dieta sazonal de Aequidens tetramerus (Cichlidae) em um igarapé da bacia do rio Machado, Rondônia, Brasil

Trophic relationships in fish communities are affected by the availability of resources, which in turn is affected by spatial and temporal variations throughout the year. The aims of this study were to characterize the diet of A. tetramerus in a streamlet in the north of Brazil and compare its composition in different hydrological seasons (wet and dry seasons). Collections were performed every two months from October 2011 to September 2012 with the aid of seine nets, hand net and fishing traps in the streamlet located in the Machado River drainage basin in the Rondônia state. Most of the specimens collected were quite small (<40 mm) and had empty stomachs. Our results showed that A. tetramerus feeds on a wide variety of items of plant origin, such as algae, seeds and leaves, as well as items of animal origin, including bryozoans, crustaceans, fish scales, terrestrial insects and detritus. The data also indicated higher consumption of aquatic insects than other food items, suggesting a primarily insect-based diet. Items of plant and allochthonous origin were consumed more in the wet season than in the dry season, but there were no seasonal differences in the consumption of animal and autochthonous items.

Relações tróficas das comunidades de peixes são afetadas por variações espaciais e temporais, que alteraram a disponibilidade de recursos ao longo do ano. Os objetivos deste estudo foram caracterizar a dieta de A. tetramerus no igarapé estudado, bem como comparar se a composição dos itens da dieta desta espécie dependem da estação hidrológica (período chuvoso e seco). As coletas foram realizadas bimestralmente, de Outubro de 2011 a Setembro de 2012, com auxílio de picaré, puçá e covos em um igarapé localizado na bacia do rio Machado no estado de Rondônia. A maioria dos espécimes eram pequenos (<40 mm) e tinham estômago vazio. Observou-se que A. tetramerus se alimenta de uma grande variedade de itens de origem vegetal, como algas, sementes e folhas; e de itens de origem animal como: briozoários, crustáceos, escamas, insetos terrestres e detritos. Constatou-se que há maior consumo de insetos aquáticos, o que sugere uma dieta insetívora. Itens de origem vegetal e alóctones foram mais consumidos na estação chuvosa do que na estação seca. Não houve diferença na composição da dieta dos peixes entre as estações de seca e chuva.

Abundance and diversity patterns of the sessile macrobenthic community associated with environmental gradients in Vitória Harbor, southeastern Brazil

Harbor terminals and urban sewage effluents affect the composition and distribution of epibenthic organisms. In this study, we hypothesized that the benthic community structure at the Vitoria Harbor changes spatially in a ~3 km scale, and that these changes are associated with environmental gradients resulting from point-source sewage and differences in the physical and chemical parameters of the water along the harbor access channel. Four sites, internal (PI), intermediate-internal (PMI), intermediate-external (PME) and external (PE), varying from 0.5 to 4.0 km off the harbor, were sampled on five quadrats at six sampling dates (N = 30 per site). The epibenthic community on the shallow sublitoral rocky shore was sampled fortnightly from December 2005 to February 2006 by point-intersection method. A total of 27 taxa were registered with higher richness and diversity values at the external sites. The similarity analysis indicated two distinct systems, with the internal sites PI and PMI apart from the external PME and PE, which showed 97% of dissimilarity. While the internal sites presented some estuarine characteristics and a high coverage (> 60%) of hydrozoans and bryozoans with silt/clay, the external ones showed coastal water influence and higher amounts of sedimentary material substrate (> 50%). This pattern reflects the estuarine gradient and the suspended sedimentary material at the internal sites, which is carried out to the external parts of the channel. The data showed two distinct benthic communities and support the hypothesis that the community structure varies along the harbor access channel in a gradient from the inner to the outer portion of the estuary.

Abundance and diversity patterns of the sessile macrobenthic community associated with environmental gradients in Vitória Harbor, southeastern Brazil

Harbor terminals and urban sewage effluents affect the composition and distribution of epibenthic organisms. In this study, we hypothesized that the benthic community structure at the Vitoria Harbor changes spatially in a ~3 km scale, and that these changes are associated with environmental gradients resulting from point-source sewage and differences in the physical and chemical parameters of the water along the harbor access channel. Four sites, internal (PI), intermediate-internal (PMI), intermediate-external (PME) and external (PE), varying from 0.5 to 4.0 km off the harbor, were sampled on five quadrats at six sampling dates (N = 30 per site). The epibenthic community on the shallow sublitoral rocky shore was sampled fortnightly from December 2005 to February 2006 by point-intersection method. A total of 27 taxa were registered with higher richness and diversity values at the external sites. The similarity analysis indicated two distinct systems, with the internal sites PI and PMI apart from the external PME and PE, which showed 97% of dissimilarity. While the internal sites presented some estuarine characteristics and a high coverage (> 60%) of hydrozoans and bryozoans with silt/clay, the external ones showed coastal water influence and higher amounts of sedimentary material substrate (> 50%). This pattern reflects the estuarine gradient and the suspended sedimentary material at the internal sites, which is carried out to the external parts of the channel. The data showed two distinct benthic communities and support the hypothesis that the community structure varies along the harbor access channel in a gradient from the inner to the outer portion of the estuary.

Abundance and diversity patterns of the sessile macrobenthic community associated with environmental gradients in Vitória Harbor, southeastern Brazil

Harbor terminals and urban sewage effluents affect the composition and distribution of epibenthic organisms. In this study, we hypothesized that the benthic community structure at the Vitoria Harbor changes spatially in a ~3 km scale, and that these changes are associated with environmental gradients resulting from point-source sewage and differences in the physical and chemical parameters of the water along the harbor access channel. Four sites, internal (PI), intermediate-internal (PMI), intermediate-external (PME) and external (PE), varying from 0.5 to 4.0 km off the harbor, were sampled on five quadrats at six sampling dates (N = 30 per site). The epibenthic community on the shallow sublitoral rocky shore was sampled fortnightly from December 2005 to February 2006 by point-intersection method. A total of 27 taxa were registered with higher richness and diversity values at the external sites. The similarity analysis indicated two distinct systems, with the internal sites PI and PMI apart from the external PME and PE, which showed 97% of dissimilarity. While the internal sites presented some estuarine characteristics and a high coverage (> 60%) of hydrozoans and bryozoans with silt/clay, the external ones showed coastal water influence and higher amounts of sedimentary material substrate (> 50%). This pattern reflects the estuarine gradient and the suspended sedimentary material at the internal sites, which is carried out to the external parts of the channel. The data showed two distinct benthic communities and support the hypothesis that the community structure varies along the harbor access channel in a gradient from the inner to the outer portion of the estuary.

Epibionts on Arenaeus cribrarius (Brachyura: Portunidae) from Brazil

Mean prevalence and intensity of infestations by epibionts were evaluated in Arenaeus cribrarius (Lamarck, 1818), based on monthly samplings (May/1991 to April/1993), in Ubatuba, Brazil. Bryozoans were quantified in terms of colony numbers and barnacles by the number of specimens. Prevalence of infestation was determined in 1,914 individuals of A. cribrarius and assessed with respect to sex, maturity stage and season. No significant interaction was detected between epibionts and biological host factors. Males showed a higher infestation rate by Chelonibia patula (Ranzani, 1818) when compared to mature non-ovigerous females, yet Octolasmis lowei Darwin, 1851 infestation was associated to adult crabs. The ovigerous females of A. cribrarius showed a higher prevalence of infestation than males and non-ovigerous females, with lower infestations being recorded during winter. A synchrony between the life cycle of the epibionts and their hosts was evident and promotes the continuity of the former in the area.

Epibionts on Arenaeus cribrarius (Brachyura: Portunidae) from Brazil

Mean prevalence and intensity of infestations by epibionts were evaluated in Arenaeus cribrarius (Lamarck, 1818), based on monthly samplings (May/1991 to April/1993), in Ubatuba, Brazil. Bryozoans were quantified in terms of colony numbers and barnacles by the number of specimens. Prevalence of infestation was determined in 1,914 individuals of A. cribrarius and assessed with respect to sex, maturity stage and season. No significant interaction was detected between epibionts and biological host factors. Males showed a higher infestation rate by Chelonibia patula (Ranzani, 1818) when compared to mature non-ovigerous females, yet Octolasmis lowei Darwin, 1851 infestation was associated to adult crabs. The ovigerous females of A. cribrarius showed a higher prevalence of infestation than males and non-ovigerous females, with lower infestations being recorded during winter. A synchrony between the life cycle of the epibionts and their hosts was evident and promotes the continuity of the former in the area.

Epibionts on Arenaeus cribrarius (Brachyura: Portunidae) from Brazil

Mean prevalence and intensity of infestations by epibionts were evaluated in Arenaeus cribrarius (Lamarck, 1818), based on monthly samplings (May/1991 to April/1993), in Ubatuba, Brazil. Bryozoans were quantified in terms of colony numbers and barnacles by the number of specimens. Prevalence of infestation was determined in 1,914 individuals of A. cribrarius and assessed with respect to sex, maturity stage and season. No significant interaction was detected between epibionts and biological host factors. Males showed a higher infestation rate by Chelonibia patula (Ranzani, 1818) when compared to mature non-ovigerous females, yet Octolasmis lowei Darwin, 1851 infestation was associated to adult crabs. The ovigerous females of A. cribrarius showed a higher prevalence of infestation than males and non-ovigerous females, with lower infestations being recorded during winter. A synchrony between the life cycle of the epibionts and their hosts was evident and promotes the continuity of the former in the area.

Contribution to the knowledge on the diet, feeding activity, and reproduction of Lolliguncula brevis (BLAINVILLE, 1823) in the coastal region off Santos (São Paulo State) / Contribuição ao conhecimento da dieta, atividade alimentar e reprodução de Lolliguncula brevis (BLAINVILLE, 1823) na região costeira de Santos (Estado de São Paulo)

This study aimed to investigate the diet and feeding activity of the squid Lolliguncula brevis in the coastal region of Santos. Sex ratio and maturity stages of the specimens were also evaluated. The sampling was carried out in September 2005 and March 2006 in Santos Bay and the continental shelf off Santos. A total of 181 specimens with 17 to 50 mm of mantle length were caught between the depths of 8.9 and 26.5 m. The sex ratio was 1.7 females:1 male; males attain gonadal maturity at smaller size than females. In both periods, most males were mature, the smallest of them measuring 23 mm of mantle length. The smallest mature female measured 32 mm, while all females larger than 40 mm were mature. The results of the digestion degree, the fullness degree and the fullness index suggest that the food intake occurs throughout the day, but with higher intensity at dusk. However, samples from the dark period of the day were not collected. The items identified in the stomach contents were crustaceans, bony fish, cephalopods, bryozoans, and nematodes. Crustaceans were the most important food for all size classes. However, as the squid body enlarged, the importance of fish in the diet increased and that of crustaceans decreased. The relative contribution of crustaceans in the diet was greater during the afternoon and dusk, and that of fish during the morning.

Este estudo teve como objetivo investigar a dieta e atividade alimentar de Lolliguncula brevis na região costeira de Santos. A amostra foi também caracterizada quanto à proporção sexual e estágio de maturação gonadal dos exemplares. As coletas foram realizadas com rede de arrasto de fundo em setembro de 2005 e março de 2006, na baía e plataforma continental ao largo de Santos. Foram coletados 181 exemplares, de 17 a 50 mm de comprimento de manto, entre 8,9 e 26,5 m de profundidade. A proporção sexual foi de 1,7 fêmeas:1 macho; machos atingem maturação gonadal com menor tamanho que as fêmeas. Nas duas épocas do ano, os machos, na maioria, estavam maduros, dos quais o menor mediu 23 mm de comprimento de manto. A menor fêmea madura mediu 32 mm, e todas com tamanho superior a 40 mm estavam maduras. Os resultados do grau de digestão do alimento, grau de repleção estomacal e Índice de Repleção sugerem que a espécie se alimenta ao longo de todo o dia, com maior intensidade ao anoitecer, no entanto, amostras da fase escura do dia não foram coletadas. Os itens identificados nos conteúdos estomacais foram crustáceos, peixes teleósteos, cefalópodes, briozoários e nematódeos. Crustáceos foram as presas mais importantes em todas as faixas de comprimento, no entanto, a importância dos peixes aumenta e a de crustáceos diminui na dieta das lulas maiores. A contribuição relativa de crustáceos n

Freshwater sponges (Porifera, Demospongiae) in a benthic filter feeding community at the Guanacaste Dry Forest, Costa Rica

The freshwater sponges Trochospongilla variabilis Bonetto & Ezcurra de Drago (1973), Radiospongilla crateriformis (Potts, 1882), Spongilla cenota Penney & Racek (1968) and Corvoheteromeyenia heterosclera (Ezcurra de Drago, 1974) compose with the sphaerid bivalve Eupera cubensis (Prime, 1865) and several Phylactolaemata bryozoans a benthic filter feeding community living in seasonal lentic and lotic habitats with high Particulate Organic Carbon (POC), low conductivity and acid pH within the Costa Rica Dry Forest biome. The sponge specimens gathered led to the re-description of the four species.

As esponjas de água doce Trochospongilla variabilis Bonetto & Ezcurra de Drago (1973), Radiospongilla crateriformis (Potts, 1882), Spongilla cenota Penney & Racek (1968) e Corvoheteromeyenia heterosclera (Ezcurra de Drago, 1974) compõem, com o bivalve esferídeo Eupera cubensis (Prime, 1865) e diversos briozoários Phylactolaemata, uma comunidade bêntica de filtradores em ambientes sazonais lênticos e lóticos com alto Carbono Orgânico Particulado (POC), baixa condutividade e pH ácido no bioma da Floresta Decidual da Costa Rica. Os espécimes de esponjas coligidos conduziram à redescrição das quatro espécies.

Freshwater sponges (Porifera, Demospongiae) in a benthic filter feeding community at the Guanacaste Dry Forest, Costa Rica

The freshwater sponges Trochospongilla variabilis Bonetto & Ezcurra de Drago (1973), Radiospongilla crateriformis (Potts, 1882), Spongilla cenota Penney & Racek (1968) and Corvoheteromeyenia heterosclera (Ezcurra de Drago, 1974) compose with the sphaerid bivalve Eupera cubensis (Prime, 1865) and several Phylactolaemata bryozoans a benthic filter feeding community living in seasonal lentic and lotic habitats with high Particulate Organic Carbon (POC), low conductivity and acid pH within the Costa Rica Dry Forest biome. The sponge specimens gathered led to the re-description of the four species.

As esponjas de água doce Trochospongilla variabilis Bonetto & Ezcurra de Drago (1973), Radiospongilla crateriformis (Potts, 1882), Spongilla cenota Penney & Racek (1968) e Corvoheteromeyenia heterosclera (Ezcurra de Drago, 1974) compõem, com o bivalve esferídeo Eupera cubensis (Prime, 1865) e diversos briozoários Phylactolaemata, uma comunidade bêntica de filtradores em ambientes sazonais lênticos e lóticos com alto Carbono Orgânico Particulado (POC), baixa condutividade e pH ácido no bioma da Floresta Decidual da Costa Rica. Os espécimes de esponjas coligidos conduziram à redescrição das quatro espécies.

Population characteristics, space use and habitat associations of the seahorse Hippocampus reidi (Teleostei: Syngnathidae)

This paper provides a case study of a threatened seahorse species, Hippocampus reidi, highlighting the importance of using ecological information to assist conservation and management initiatives. Underwater visual sighting data (50 x 2m transect) gathered along the NE, SE and S portions of the Brazilian coast revealed an unequal distribution across localities, perhaps related to harvesting pressure, and a mean density of 0.026 ind.m-2. Our findings suggest some restricted spatial use by H. reidi, which was consistent with its estimated home range, and with re-sighting of specimens. Reproduction was recorded year-round, however productive peaks may exist. Components of habitat structure mostly used as anchoring points were mangrove plants, macroalgae, cnidarians, seagrass, sponges, and bryozoans. Conservation recommendations include: further characterization and mapping of habitats; assessment of availability and condition of microhabitats in selected areas, and studies on dispersal routes during initial life stages(AU)

Neste artigo apresenta-se um estudo de caso de uma espécie ameaçada de cavalo-marinho, Hippocampus reidi, enfatizando a importância de utilizar informações ecológicas nas ações de conservação e manejo. Dados de censo visual (transectos de 50 x 2m) obtidos nas porções NE, SE e S da costa brasileira revelaram uma distribuição heterogênea entre as localidades, talvez relacionada à pressão de coleta, e uma densidade média de 0.026 ind.m-2. Os resultados sugerem limitação no uso do espaço por H. reidi (consistente com a área vital estimada e com a re-avistagem de exemplares) e que a reprodução ocorre o ano inteiro, embora com possíveis picos. Os componentes da estrutura do habitat mais freqüentemente utilizados como pontos de ancoragem pelos cavalos-marinhos foram vegetação de mangue, macroalgas, cnidários, capim marinho e briozoários. Recomendações conservacionistas incluem caracterização adicional e mapeamento de habitats; avaliação da disponibilidade e condição dos microhabitats em áreas selecionadas, e estudos sobre rotas de dispersão durante as fases iniciais de vida(AU)

Macroepizoísmo em Libinia ferreirae (Crustacea, Brachyura, Majidae)

A study of the distribution of the macroepizoites was carried out on a population of the spider crab Libinia ferreirae Brito Capello, 1871 from the Southern Brazilian coast. Crabs were obtained from shrimps and fishes by-catch. They were measured, and their macroepizoites were identified and counted. The following sessile macroepizoites were registered: Calliactis tricolor (Lesueur, 1817) (Cnidaria); Actiniaria (Cnidaria); Arca sp. (Mollusca); Ostreidae (Mollusca); Acanthodesia tenuis (Desor, 1848) (Bryozoa); Cirripedia and two species of Gammaridea (Crustacea). The sea anemone C. tricolor was the most frequent species and probably it is used as a mechanism of camouflage by crabs. Macroepizoites on L. ferreirae are related to its age or size, therefore, bigger or older crabs had greater incidence of macroepizoites. However, the density of macroepizoites is about three per crab. There is not a relationship between macroepizoism and sex of the host, but ovigerous females use this resource more frequently than non-ovigerous ones. Due to larger setting area, macroepizoites colonize mainly the carapace of the host; bryozoans predominate in hosts' pereiopods.

Um estudo de distribuição dos macroepizóicos foi realizado numa população do caranguejo-aranha Libinia ferreirae Brito Capello, 1871 proveniente do litoral dos estados do Paraná e de Santa Catarina. O material biológico foi obtido junto aos pescadores, e faz parte do rejeito de pesca. Os caranguejos foram mensurados e os macroepizóicos identificados e contados. Os seguintes macroepizóicos sésseis foram registrados: Calliactis tricolor (Lesueur, 1817) (Cnidaria); Actiniaria (Cnidaria); Arca sp. (Mollusca); Ostreidae (Mollusca); Acanthodesia tenuis (Desor, 1848) (Bryozoa); Cirripedia e duas espécies tubícolas de Gammaridea (Crustacea). Além destes organismos ocorreram dois tubos desabitados e quatro animais vágeis. A anêmona C. tricolor foi a espécie mais abundante e freqüente, sendo, provavelmente, utilizada como mecanismo de camuflagem pelo caranguejo. O macroepizoísmo em L. ferreirae está relacionado com a idade ou tamanho do caranguejo, tendo maior incidência naqueles mais velhos ou de maior porte. Entretanto, a densidade dos macroepizóicos por caranguejo se mantém em torno de três. Não há relação entre o macroepizoísmo e o sexo do hospedeiro; somente fêmeas ovígeras utilizam desse recurso mais freqüentemente do que as não-ovígeras. Devido à maior área de fixação, os macroepizóicos colonizam principalmente a carapaça do caranguejo, enquanto nos pereiópodos há predominância de Bryozoa.

Macroepizoísmo em Libinia ferreirae (Crustacea, Brachyura, Majidae)

A study of the distribution of the macroepizoites was carried out on a population of the spider crab Libinia ferreirae Brito Capello, 1871 from the Southern Brazilian coast. Crabs were obtained from shrimps and fishes by-catch. They were measured, and their macroepizoites were identified and counted. The following sessile macroepizoites were registered: Calliactis tricolor (Lesueur, 1817) (Cnidaria); Actiniaria (Cnidaria); Arca sp. (Mollusca); Ostreidae (Mollusca); Acanthodesia tenuis (Desor, 1848) (Bryozoa); Cirripedia and two species of Gammaridea (Crustacea). The sea anemone C. tricolor was the most frequent species and probably it is used as a mechanism of camouflage by crabs. Macroepizoites on L. ferreirae are related to its age or size, therefore, bigger or older crabs had greater incidence of macroepizoites. However, the density of macroepizoites is about three per crab. There is not a relationship between macroepizoism and sex of the host, but ovigerous females use this resource more frequently than non-ovigerous ones. Due to larger setting area, macroepizoites colonize mainly the carapace of the host; bryozoans predominate in hosts' pereiopods.

Um estudo de distribuição dos macroepizóicos foi realizado numa população do caranguejo-aranha Libinia ferreirae Brito Capello, 1871 proveniente do litoral dos estados do Paraná e de Santa Catarina. O material biológico foi obtido junto aos pescadores, e faz parte do rejeito de pesca. Os caranguejos foram mensurados e os macroepizóicos identificados e contados. Os seguintes macroepizóicos sésseis foram registrados: Calliactis tricolor (Lesueur, 1817) (Cnidaria); Actiniaria (Cnidaria); Arca sp. (Mollusca); Ostreidae (Mollusca); Acanthodesia tenuis (Desor, 1848) (Bryozoa); Cirripedia e duas espécies tubícolas de Gammaridea (Crustacea). Além destes organismos ocorreram dois tubos desabitados e quatro animais vágeis. A anêmona C. tricolor foi a espécie mais abundante e freqüente, sendo, provavelmente, utilizada como mecanismo de camuflagem pelo caranguejo. O macroepizoísmo em L. ferreirae está relacionado com a idade ou tamanho do caranguejo, tendo maior incidência naqueles mais velhos ou de maior porte. Entretanto, a densidade dos macroepizóicos por caranguejo se mantém em torno de três. Não há relação entre o macroepizoísmo e o sexo do hospedeiro; somente fêmeas ovígeras utilizam desse recurso mais freqüentemente do que as não-ovígeras. Devido à maior área de fixação, os macroepizóicos colonizam principalmente a carapaça do caranguejo, enquanto nos pereiópodos há predominância de Bryozoa.

Invertebrate dispersal by waterbird species in neotropical wetlands

Abstract Endozoochory by waterbirds is particularly relevant to the dispersal of non-flying aquatic invertebrates. This ecological function exercised by birds has been demonstrated in different biogeographical regions, but there are no studies for the neotropical region. In this work, we identified propagules of invertebrates in faeces of 14 syntopic South American waterbird species representing six families, and hatched additional invertebrates from cultured faeces. We tested whether propagule abundance, species richness and composition varied among bird species, and between the cold and warm seasons. We found 164 invertebrate propagules in faecal samples from seven different waterbirds species, including eggs of the Temnocephalida and Notonectidae, statoblasts of bryozoans (Plumatella sp.) and ephippia of Cladocera. Ciliates (including Paramecium sp. and Litostomatea), nematodes and rotifers (Adineta sp. and Nottomatidae) hatched from cultured samples. Potential for endozoochory was confirmed for 12 of 14 waterbird species. Our statistical models suggest that richness and abundance of propagules are associated with bird species and not affected by seasonality. Dispersal by endozoochory is potentially important to a broad variety of invertebrates, being promoted by waterbirds with different ecological and morphological traits, which are likely to drive the dispersal of invertebrates in neotropical wetlands.

Resumo A endozoocoria promovida por aves aquáticas é particularmente relevante para a dispersão de invertebrados aquáticos não-voadores. Essa função ecológica exercida pelas aves tem sido demonstrada para diferentes regiões biogeográficas, porém, não existem estudos para a região neotropical. Neste trabalho nós identificamos propágulos de invertebrados encontrados em fezes de 14 espécies sintópicas de aves aquáticas da América do Sul, representando seis famílias de aves, e também invertebrados emergidos de amostras fecais cultivadas em laboratório. Testamos se a abundância, riqueza de espécies e composição de propágulos de invertebrados variavam entre as espécies de aves e entre estações. Nós encontramos 164 propágulos de invertebrados em amostras fecais de sete espécies de aves, incluindo ovos de Temnocephalida e Notonectidae, estatoblastos de briozoários (Plumatella sp.) e efípios de Cladocera. Ciliados (incluindo Paramecium sp. e Litostomatea), nematóides e rotíferos (Adineta sp. e Nottomatidae) eclodiram de amostras cultivadas. O potencial para endozoocoria foi confirmado para 12 das 14 espécies de aves aquáticas investigadas. Nossos modelos estatísticos sugerem que a riqueza e abundância de propágulos estão associadas às espécies de aves e não são afetadas pela sazonalidade. A dispersão por endozoocoria é importante para uma ampla variedade de invertebrados, sendo promovida por aves aquáticas com diferentes características ecológicas e morfológicas as quais provavelmente regulam a dispersão de invertebrados entre áreas úmidas neotropicais.