ABSTRACT
A single Pomacanthus maculosus was filmed during a scuba diving survey on a rocky reef from southern Brazil. The body shape and coloration pattern confirmed the species identification. The biological and ecological characteristics of P. maculosus and the long distance of Brazil from its original distribution strongly suggest of an anthropogenic pathway of dispersion.
Subject(s)
Introduced Species , Perciformes/physiology , Animal Distribution , Animals , Atlantic Ocean , Brazil , Perciformes/anatomy & histology , Perciformes/classificationABSTRACT
This study aimed to describe the growth parameters of Anchoa tricolor in a subtropical estuary. From August 2010 to July 2011, 10.009 specimens of the anchovy Anchoa tricolor, mean total length 4.2 cm (±1.45), were captured in the intertidal region of the Estuarine Complex of Paranaguá (25º 15' - 25° 35' S and 48° 20' - 48° 45' W). Species´s weight/length relationship for grouped genders was described as follow: W = 0.0000591.Lt3.282 (length in centimeters; weight in grams) showing a positive allometric growth pattern (b>3; P=0.000). Significant differences concerning weight/length relationship for males, females and unsexed individuals were identified. Parameters of the length to age growth curve were estimated by adjusting a von Bertalanffy growth equation from aged individuals from a length-frequency distribution: L∞ = 10.06 (1-e-17715(t + 0.205)) (length in centimeters, age in years). The age to attain 95% of the asymptotic length ( A95 ; longevity sensu Taylor) was estimated at 1.7 years. Size frequency distributions indicate that A. tricolor uses the estuarine area as reproductive and growing grounds, especially during the first year of the life cycle, where the species represent a key element for ecosystem functioning due to relatively high abundance and energy transference from plankton to top predators.
ABSTRACT
Specimens of Brazilian silverside (Atherinella brasiliensis, n=9672) with a length range of 1.5 to 14.2 cm were captured in the intertidal areas of the Estuarine Complex of Paranaguá, Brazil, between August 2010 and July 2011. The species' weight-length relationship was represented by the equation W=0.00533 L3.136 with a slightly positive allometry (b>3) and could be divided into two growth stanzas: W = W1 + W2; Stanza 1: W1= SW. (0.005239 L3.152); Stanza 2: W2= (1 - SW). (0.000699 L3.913); Switch-Function: SW = [1 + e1.204 (L - 11.66)]-1. The breakpoint between the first and second stanza (11.66 cm) matches published values for the estimated size at first maturity of adult females. Frequency distributions indicate that the species is present in the shallow areas of the Estuarine Complex of Paranaguá during all phases of its ontogenetic development, with the recruitment of juveniles taking place between October and November. Modal displacement was monitored throughout 12 months. The von Bertalanffy growth model and longevity was estimated as follow: asymptotic length (L∞) of 17.5 cm, growth coefficient (K) of 0.89 (year-1) and longevity (A95) of 3.33 years. We present some considerations with regard to the general methodology for adjusting weight-length relationships.
Subject(s)
Body Size , Body Weight , Fishes/growth & development , Animals , Brazil , LongevityABSTRACT
Red and black groupers are large-bodied opportunistic ambush predators commonly found in Southwestern Atlantic tropical reefs. We investigated the diet of both species in order to detail ontogenetic, spatial and temporal trends, and to assess the extent of overlap in resource use between these two sympatric predators on the Abrolhos Bank, Brazil. Decapods and fishes were the main food items of Epinephelus morio while fishes were the main prey of Mycteroperca bonaci. Both diets were significantly influenced by body size and habitat, but only smaller individuals of E. morio feed almost exclusively on crustaceans. While the two groupers rely on many of the same prey types, coexistence may be facilitated by E. morio feeding more heavily on crustaceans, particularly the blackpoint sculling crab Cronius ruber, while black grouper take comparatively few crustaceans but lots of fish prey. Predators like red and black groupers could trigger indirect effects in the community and influence a large range of ecological processes, such as linkages between top and intermediate predators, and intermediate predators and their resources.(AU)
A garoupa e o badejo-verdadeiro são predadores oportunistas de grande porte, com estratégia de emboscada, comumente encontrados em recifes tropicais do Atlântico Sul. A dieta das duas espécies foi investigada, avaliando influências ontogenéticas, espaciais e temporais, assim como a sobreposição no uso de recursos entre estes dois predadores co-orrentes no Banco dos Abrolhos, Brasil. Decápodes e peixes foram os principais itens alimentares de Epinephelus morio, enquanto que os peixes foram as principais presas de Mycteroperca bonaci. Ambas as dietas foram significativamente influenciadas pelo tamanho corporal e habitat, mas apenas indivíduos menores de E. morio alimentaram-se quase que exclusivamente de crustáceos. Como as duas espécies utilizam muitas presas semelhantes, a coexistencia parece ser facilitada pelo fato de E. morio se alimentar principalmente de crustáceos, particularmente do caranguejo Cronius ruber, enquanto que o badejo-verdadeiro consome relativamente poucos crustáceos e grande quantidade de peixes. Predadores como as espécies estudadas podem causar efeitos indiretos na comunidade e influenciar uma grande variedade de processos ecológicos, como conexões entre predadores de topo e intermediários e predadores intermediários e seus recursos.(AU)
Subject(s)
Animals , Nutrition Ecology , Perciformes/classification , Food Chain , EatingABSTRACT
Red and black groupers are large-bodied opportunistic ambush predators commonly found in Southwestern Atlantic tropical reefs. We investigated the diet of both species in order to detail ontogenetic, spatial and temporal trends, and to assess the extent of overlap in resource use between these two sympatric predators on the Abrolhos Bank, Brazil. Decapods and fishes were the main food items of Epinephelus morio while fishes were the main prey of Mycteroperca bonaci. Both diets were significantly influenced by body size and habitat, but only smaller individuals of E. morio feed almost exclusively on crustaceans. While the two groupers rely on many of the same prey types, coexistence may be facilitated by E. morio feeding more heavily on crustaceans, particularly the blackpoint sculling crab Cronius ruber, while black grouper take comparatively few crustaceans but lots of fish prey. Predators like red and black groupers could trigger indirect effects in the community and influence a large range of ecological processes, such as linkages between top and intermediate predators, and intermediate predators and their resources.(AU)
A garoupa e o badejo-verdadeiro são predadores oportunistas de grande porte, com estratégia de emboscada, comumente encontrados em recifes tropicais do Atlântico Sul. A dieta das duas espécies foi investigada, avaliando influências ontogenéticas, espaciais e temporais, assim como a sobreposição no uso de recursos entre estes dois predadores co-orrentes no Banco dos Abrolhos, Brasil. Decápodes e peixes foram os principais itens alimentares de Epinephelus morio, enquanto que os peixes foram as principais presas de Mycteroperca bonaci. Ambas as dietas foram significativamente influenciadas pelo tamanho corporal e habitat, mas apenas indivíduos menores de E. morio alimentaram-se quase que exclusivamente de crustáceos. Como as duas espécies utilizam muitas presas semelhantes, a coexistencia parece ser facilitada pelo fato de E. morio se alimentar principalmente de crustáceos, particularmente do caranguejo Cronius ruber, enquanto que o badejo-verdadeiro consome relativamente poucos crustáceos e grande quantidade de peixes. Predadores como as espécies estudadas podem causar efeitos indiretos na comunidade e influenciar uma grande variedade de processos ecológicos, como conexões entre predadores de topo e intermediários e predadores intermediários e seus recursos.(AU)
Subject(s)
Animals , Nutrition Ecology , Perciformes/classification , Food Chain , EatingABSTRACT
ABSTRACT Specimens of Brazilian silverside (Atherinella brasiliensis, n=9672) with a length range of 1.5 to 14.2 cm were captured in the intertidal areas of the Estuarine Complex of Paranaguá, Brazil, between August 2010 and July 2011. The species' weight-length relationship was represented by the equation W=0.00533 L3.136 with a slightly positive allometry (b>3) and could be divided into two growth stanzas: W = W1 + W2; Stanza 1: W1= SW. (0.005239 L3.152); Stanza 2: W2= (1 - SW). (0.000699 L3.913); Switch-Function: SW = [1 + e1.204 (L - 11.66)]-1. The breakpoint between the first and second stanza (11.66 cm) matches published values for the estimated size at first maturity of adult females. Frequency distributions indicate that the species is present in the shallow areas of the Estuarine Complex of Paranaguá during all phases of its ontogenetic development, with the recruitment of juveniles taking place between October and November. Modal displacement was monitored throughout 12 months. The von Bertalanffy growth model and longevity was estimated as follow: asymptotic length (L∞) of 17.5 cm, growth coefficient (K) of 0.89 (year-1) and longevity (A95) of 3.33 years. We present some considerations with regard to the general methodology for adjusting weight-length relationships.
Subject(s)
Animals , Body Weight , Body Size , Fishes/growth & development , Brazil , LongevityABSTRACT
Using monthly otter-trawl deployments, spatial and temporal variability among the relative densities of marine debris were assessed in the Paranaguá estuarine complex; a subtropical World Heritage Listed area in southern Brazil. During 432 deployments over 12 months, 291 marine debris items were identified; of which most (92%) were plastic, and more specifically shopping bags, food packages, candy wrappers and cups typically >21 mm long. The most contaminated sectors were those closest to Paranaguá city and the adjacent port, and had up to 23.37±3.22 pieces ha(-1). Less urbanized sectors had between 12.84±1.49 and 9.32±1.10 pieces ha(-1). Contamination did not vary between dry or wet seasons, but rather was probably affected by consistent urban disposal and localized hydrological processes. Marine debris might be minimized by using more environment friendly materials, however a concrete solution requires adequately integrating local government and civil society.
Subject(s)
Waste Products/analysis , Water Pollution/analysis , Brazil , Environmental Monitoring/methods , Estuaries , Food Packaging , Plastics , SeasonsABSTRACT
The catchability of three type seine nets was compared in seven estuarine beaches of Sao Francisco do Sul, Santa Catarina. The capture of specimens and taxa was higher in the net 2.5 mm mesh with nets of meshes 1 and 2.5 mm showing a higher number of unique species. In general terms it was noted that the nets of meshes 1 and 2.5mm capture a greater number of specimens of smaller size. In most months the average collection for net and the number of fish species, Shannon-Wiener and equitability not differ significantly. Considering the beaches separately, between the nets used in the collections were not significant differences between the mean number of specimens and equitability, with differences in the average number of fish and Shannon-Wiener. Through cluster analysis shows that nets of meshes of 2.5 and 5.0 mm shown in estuarine beaches studied in assemblies similar pattern of temporal variation, differing markedly from the temporal pattern identified with the net of mesh 1mm. In spatial terms the three nets showed different results, with a greater similarity between the assemblages sampled by nets of 2.5 and 5mm.
A capturabilidade de três redes tipo picaré foi comparada em sete praias estuarinas de São Francisco do Sul, Santa Catarina. A captura de exemplares e taxa foi maior na rede de malha de 2,5 mm, com as redes de malhas de 1 e 2,5 mm apresentando um maior número de espécies exclusivas. Em termos gerais observou-se que as redes de malha de 1mm e 2,5mm capturam um maior número de exemplares de menor porte. Na maioria dos meses de coleta as médias por rede do número de peixes e espécies, diversidade de Shannon-Wiener e a equitavidade não diferiram significativamente. Considerando-se as praias em separado, entre as redes utilizadas nas coletas não foram significativas as diferenças entre as médias do número de exemplares e equittividade, com diferenças estatísticas na média do número de peixes e diversidade de Shannon-Wiener. Através das análises de agrupamento observa-se que as redes de malha de 2,5 mm e 5,0 mm mostraram, nas praias estuarinas estudadas, assembléias similares no padrão de variação temporal, diferindo acentuadamente do padrão temporal identificado com a rede de malha de 1mm. Em termos espaciais as três redes mostraram resultados diferentes, com uma maior similaridade entre as assembléias amostradas pelas redes de 2,5 e 5mm.
Subject(s)
Animals , Animal Distribution , Estuaries , Fishes , Bathing BeachesABSTRACT
The catchability of three type seine nets was compared in seven estuarine beaches of Sao Francisco do Sul, Santa Catarina. The capture of specimens and taxa was higher in the net 2.5 mm mesh with nets of meshes 1 and 2.5 mm showing a higher number of unique species. In general terms it was noted that the nets of meshes 1 and 2.5mm capture a greater number of specimens of smaller size. In most months the average collection for net and the number of fish species, Shannon-Wiener and equitability not differ significantly. Considering the beaches separately, between the nets used in the collections were not significant differences between the mean number of specimens and equitability, with differences in the average number of fish and Shannon-Wiener. Through cluster analysis shows that nets of meshes of 2.5 and 5.0 mm shown in estuarine beaches studied in assemblies similar pattern of temporal variation, differing markedly from the temporal pattern identified with the net of mesh 1mm. In spatial terms the three nets showed different results, with a greater similarity between the assemblages sampled by nets of 2.5 and 5mm.(AU)
A capturabilidade de três redes tipo picaré foi comparada em sete praias estuarinas de São Francisco do Sul, Santa Catarina. A captura de exemplares e taxa foi maior na rede de malha de 2,5 mm, com as redes de malhas de 1 e 2,5 mm apresentando um maior número de espécies exclusivas. Em termos gerais observou-se que as redes de malha de 1mm e 2,5mm capturam um maior número de exemplares de menor porte. Na maioria dos meses de coleta as médias por rede do número de peixes e espécies, diversidade de Shannon-Wiener e a equitavidade não diferiram significativamente. Considerando-se as praias em separado, entre as redes utilizadas nas coletas não foram significativas as diferenças entre as médias do número de exemplares e equittividade, com diferenças estatísticas na média do número de peixes e diversidade de Shannon-Wiener. Através das análises de agrupamento observa-se que as redes de malha de 2,5 mm e 5,0 mm mostraram, nas praias estuarinas estudadas, assembléias similares no padrão de variação temporal, diferindo acentuadamente do padrão temporal identificado com a rede de malha de 1mm. Em termos espaciais as três redes mostraram resultados diferentes, com uma maior similaridade entre as assembléias amostradas pelas redes de 2,5 e 5mm.(AU)
Subject(s)
Animals , Fishes , Estuaries , Bathing Beaches , Animal DistributionABSTRACT
Abundance and diversity of the fish fauna in the shallow infralittoral region of Atami Beach, Paraná, Brazil, were studied through monthly collections between July 1998 and June 1999. A total of 7553 fishes from 70 species and 26 families, mainly juvenile forms, was captured in the area. The mean captures in number of species, number of fish and biomass were larger from the end of spring to the middle of autumn; seasonal tendency in richness, diversity (number) and equitability indices were not observed. The largest mean dissimilarity in the composition of the ichthyofauna occurred between June and May in comparison to the period between July and October. The species that contributed most to this dissimilarity were Selene setapinnis (Mitchill, 1815), Conodon nobilis (Linnaeus, 1758) and Stellifer rastrifer (Jordan, 1889). Three great groups reflecting patterns of temporal occurrence of the most abundant species were identified.