Resumo Objetivo O objetivo foi descrever os parâmetros LWR das espécies nativas e não nativas do rio Guaraguaçu e comparar esses parâmetros das espécies não nativas obtidos no rio Guaraguaçu com os parâmetros de LWR dos seus locais de distribuição nativa disponível na literatura. Métodos Os exemplares foram coletados semestralmente entre 2004 e 2007, usando diferentes técnicas de amostragens. Resultados No total, foram analisados 673 exemplares de 10 espécies. Seis espécies apresentaram alometria positiva (b>3) e três alometria negativa (b<3) e isometria (b=3). Espécies nativas possuem parâmetros de LWR idênticos a estudos prévios, exceto Centropomus parallelus, a qual apresentou isometria neste estudo. As espécies não nativas Clarias gariepinus e Ictalurus punctatus demonstraram diferenças significativas entre os parâmetros de LWR do Guaraguaçu e das suas áreas de distribuição nativa. Oreochromis niloticus não apresentou diferença significativa entre os parâmetros de LWR entre o Guaraguaçu e sua área nativa de distribuição. Conclusões O resultado indica que as condições ambientais talvez não influenciem o crescimento das espécies não nativas, o que explicaria o sucesso de invasão destas espécies.

Abstract Aim The objective was to describe the LWR of fish species of the Guaraguaçu River, as well as to compare the LWR parameters of the non-native species with the parameters obtained in their native ranges, available in the literature. Methods In this study, the LWR of 10 fish species of the Guaraguaçu River, southern Brazil, were analyzed. Fish were sampled semiannually between 2004 and 2007, using different sampling techniques in the Guaraguaçu River. Results A total of 673 specimens of 10 species were captured. The LWR demonstrated a prevalence of species (six out of 10) with positive allometric growth (b > 3). The remaining species presented isometric (b = 3, two species) or negative growth (b < 3, two species). Native species exhibited the same LWR from previous studies, except Centropomus parallelus, which presented an isometric growth in this study. The non-native species Clarias gariepinus and Ictalurus punctatus showed significant differences between the LWR parameters in the Guaraguaçu River and in their native distribution, but the same growth pattern. Oreochromis niloticus did not present significant differences in the allometric coefficient from its native range. Conclusions These results indicate that different environmental conditions may not influence the growth pattern of non-native species, which explains their invasion success due to high adaptability to new environments.

ABSTRACT Menticirrhus americanus were sampled (n = 393) from two beaches (P1 is an estuarine beach near the mouth of the Paranaguá Estuarine Complex, and P2 is a beach adjacent to the Paranaguá Estuarine Complex) in the subtropical region of the western South Atlantic waters between August 2015 and June 2016. This study aimed to identify the spawning season and the age structure for M. americanus using two sampling methods. For sampling at the P1 beach, seine, line, and pole were used, while samples from the P2 beach were obtained from the artisanal fishers. Females were numerically dominant in all sampling months at both sites except for February when the males became dominant. The species exhibited a protected reproductive season with multiple spawning peaks between August and December. Males and females were captured at all gonadal development stages and ages between 1 and 6 from both sites. At first maturity, the length of the females was 16.3 cm, and the mean age at first maturity was 1.3 years. Individuals aged between 1 and 3 years were dominant (68%). The results suggested that young and adults of the M. americanus use the same habitats throughout their ontogeny.

Resumo: Objetivo Este artigo tem como objetivo reunir e atualizar os registros de espécies não-nativas em um rio subtropical do sul do Brasil, alertando para os impactos que podem exercer neste, e em outros corpos hídricos. Métodos Foi realizado um monitoramento no rio Guaraguaçu, o maior rio da planície costeira do Paraná, localizado no bioma Mata Atlântica. Os peixes foram amostrados em dois períodos: de 2002 a 2007 (mensalmente) e de 2016 a 2018 (semestralmente), e os demais organismos foram coletados em amostragens isoladas. Resultados O monitoramento registrou a presença de seis espécies de animais não-nativos neste rio – quatro espécies de peixe (Clarias gariepinus, Ictalurus punctatus, Oreochromis niloticus e Salminus brasiliensis), um invertebrado (Macrobrachium rosenbergii) e um foraminífero (Ammoglobigerina globigeriniformis), introduzidos principalmente através de escapes de aquicultura, para pesca esportiva ou por água de lastro. Tais introduções são um problema, pois, têm o potencial de impactar negativamente as espécies nativas ameaçadas de extinção neste rio através de predação, competição ou introdução de novas doenças. Conclusões No rio Guaraguaçu o crescente número de introduções é preocupante, pois estas espécies têm em comum um conjunto de características que as tornam potenciais invasoras. Continuar o monitoramento de suas populações é fundamental para detectar e minimizar seus impactos negativos na biota nativa, uma vez que há na região uma unidade de conservação (Estação Ecológica Guaraguaçu), com o objetivo de proteger o ambiente em sua condição prístina.

Abstract: Aim This paper aims to concatenate and update the records of non-native species in a subtropical River, in Southern Brazil, warning about their possible impacts in this and other water bodies. Methods Monitoring was carried out in the Guaraguaçu River, the largest River of the Paraná coastal plain, located in the Atlantic Rainforest biome. Fishes were sampled in two periods: from 2002 to 2007 (monthly) and from 2016 to 2018 (semiannually), and the other organisms were collected in isolated samplings. Results The monitoring recorded the presence of six non-native species of animals in this River – four species of fish (Clarias gariepinus, Ictalurus punctatus, Oreochromis niloticus and Salminus brasiliensis), one invertebrate (Macrobrachium rosenbergii) and one foraminifera (Ammoglobigerina globigeriniformis) introduced by escapes from aquaculture, sport fishing and ballast water. These introductions are problematic because they have the potential to impact upon the endangered native species in the River through predation, competition or novel diseases. Conclusions In Guaraguaçu River the increasing number of introductions is worrying because these species have in common a set of traits that turns them into potential invaders. It is of great importance to keep monitoring their populations in order to detect and minimize their negative impacts on native biota, once there is a conservation unit in the region (Guaraguaçu Ecological Station), with the aim to protect the environment in its pristine condition.

Abstract The objective of this study was to describe the morphology and morphometry of saggitta otoliths of Polydactylus virginicus, Menticirrhus cuiaranensis and Conodon nobilis in a tropical environment. Fishes were caught with rod and reel in competitive fishing events promoted in 2014-2015 along the coast of Sergipe. A total of 174 pairs of sagitta otoliths of P. virginicus, 181 of M. cuiaranensis and 77 of C. nobilis was extracted. In general, the sagitta otoliths of all three species analyzed here presented different morphology and shape indices. The permutational multivariate analysis of variance (PERMANOVA) demonstrated significant differences among species and ontogenetic phases within each species using morphometry and shape indices. The linear discriminant analysis (LDA) presented a 98.3% correct reclassification of the otoliths by species.

Abstract This study aimed to verify variations in the form of the sagitta otolith of Menticirrhus americanus as to their ontogeny, sex and stage of such structure. Ontogenetically were found significant differences (p < 0.05) for all shape indices (aspect ratios, shape factor, rectangularity, ellipticity, relative surface of sulcus acusticus) and also in the wavelet of the otolith. The CVA presented a 98.6% correct reclassification of the otolith between interval class. Sexual variations were found in the wavelet and in the relative surface of sulcus acusticus index. Between adult females and young females, differences were not detected in the wavelet and rectangularity, but significant differences were found in all other shape indices. The CVA presented a 79.6% correct reclassification of the otolith of the sexes and stages of life sampled. Young females and adults females showed highest correct percentage of classification. The results of this study demonstrate for the first time the influence of the ontogenetic variation and sexual in the form of the otoliths.

The objective of the present study was to evaluate the use of sagitta otolith microchemistry (Sr:Ca, Ba:Ca ratios) as habitat indicator of Anchoa tricolor between the estuary and the adjacent continental shelf. We analyzed 162 specimens of A. tricolor in the Paranaguá Estuarine Complex (Brazil), and salinity and rainfall data. The biological and environmental data were grouped into sectors (internal, intermediate, and external) and periods (early and late wet, and dry periods). The concentrations of Ca, Ba and Sr were determined using an ICP-OES. The Sr:Ca ratio indicated the existence of two groups, probably from different origins, that use the estuary at the same time, but occupying different sectors of the estuary. The Ba:Ca ratio did not differentiate the groups as to the use of estuary, but rather revealed low values, suggesting that this species does not use freshwater environments. However, this ratio showed a high variation in the wet period, indicating a greater availability of barium in the estuarine regions affected by the river discharge. Considering our results, it is possible to classify A. tricolor as an estuarine migrant species. Also, the Sr:Ca and Ba:Ca ratios can be indicative of the habitat use in a subtropical estuary.

Resumo As capturas incidentais de peixes no arrasto do camarão representam um recurso abundante para a alimentação de muitas aves, sobretudo para a gaivota Larus dominicanus. O presente estudo avaliou a influência do defeso da pesca de arrasto do camarão sobre a dieta de L. dominicanus no litoral do estado do Paraná. Entre dezembro de 2013 e agosto de 2014 foram coletados 10 pellets alimentares por mês em duas áreas distintas, em períodos sem e com a influência do defeso do camarão sete-barbas. Ao todo, foram identificados 920 peixes, divididos em quatro famílias e 15 espécies, com destaque para a família Sciaenidae, com 11 espécies. Foram identificadas diferenças na abundância e biomassa das espécies entre as áreas e entre os períodos de pré-defeso, defeso e pós-defeso. Diferenças em relação ao comprimento total médio das espécies só foram encontradas entre o pré-defeso e defeso em uma das áreas. Com este trabalho, foi possível observar a forte relação entre L. dominicanus e a pesca de arrasto do camarão, a composição das espécies identificadas nos pellets e as estimativas de comprimento seguem o mesmo padrão do que a literatura traz para os peixes descartados nas atividades de arrasto.

Abstract Fish that are incidentally caught by shrimp trawling represent a predictable and abundant resource for feeding several bird species, especially for the gull Larus dominicanus. This fishing activity is subject to disruptions throughout the year during closed fishing seasons, when other fishing modalities are exercised, which can alter the composition, abundance and size of the fish bycatch. This study evaluated the influence of the restriction of fishing period of shrimp (closed season) on the diet of L. dominicanus, on the Paraná State coast. From December 2013 to August 2014, 10 pellets were collected per month in two distinct areas that have shrimp trawl fishery as the main economic activity: one continental and another in an estuarine island. In total, 920 fish were identified, divided into four families and 15 species, especially the family Sciaenidae with 11 species. There were differences in abundance and biomass of species between areas and between seasons of pre-closure, closure and post-closure. Differences for the mean total length of the species were only detected between the pre-closed and closed seasons in one area. This study evidenced the strong relationship between L. dominicanus and the shrimp trawl fishery, the species composition identified in the pellets and their respective morphometric measurements follow the same pattern of the literature for fish discarded in trawling activities.