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The article presents a research study regarding the non-standard fishing of large sharks in Paraná, Brazil. Research shows the shark species that are being fished in the state including Elasmobranch, Trichiuridae, Rhinopteridae, and rays and 60 specimens have already recorded. Furthermore, dusky sharks are commonly caught by Brazilian fishermen in the coastal area of the state.

Simple Summary: Otolith geochemical signatures were important tools used to investigate the population of commercially exploited fish species. Historical and contemporary otolith samples of Isopisthus parvipinnis, Bigtooth corvina, an economically and ecologically important Brazilian fish species, collected in five subareas [São Paulo: North—NSP, Center—CSP and South—SSP; Paraná (PR) and Santa Catarina (SC)] of the shallow waters off the coast of the South Brazil Bight were used in this study. Univariate and multivariate statistical analyses showed spatial differences in otolith chemical composition over the years, suggesting that long-term temporal variability in oceanographic conditions, anthropogenic influence, and climate change on this coastal ecosystem influenced the geochemical signatures. Moreover, these results also confirm that I. parvipinnis is not a single and homogeneous fish stock in this geographic area, supporting the existence of a metapopulation structure scenario and corroborating previous studies that used alternative, complementary phenotypic tags. In this study, otolith geochemical signatures (Element:Ca ratios) were used to investigate the long-term spatial shifts of the population structure of Isopisthus parvipinnis, Bigtooth corvina, an economically and ecologically important Brazilian fish species. Two-hundred and ninety-seven juvenile individuals from historical (1975) and contemporary (2018/2019) samples were collected in five subareas [São Paulo: North—NSP, Center—CSP and South—SSP; Paraná (PR) and Santa Catarina (SC)] of the shallow waters off the coast of the South Brazil Bight were analyzed. The main informative single elements were Co:Ca, Cu:Ca, Li:Ca, Mg:Ca, Mn:Ca, Ni:Ca, Na:Ca, and Rb:Ca. Multivariate analysis showed spatial differences in otolith chemical composition over the years. Samples from 1975 presented an overall low reclassification rate (58%), suggesting the existence of two population units: (1) SP + PR; and (2) SC. However, samples from 2018/2019 discriminated four distinct population units with a good overall reclassification (80%): (1) NSP; (2) CSP; (3) SSP + PR; and (4) SC. This spatial differentiation on the geochemical signatures probably reflects the effects of long-term temporal variability in oceanographic conditions, anthropogenic influence, and climate change on this coastal ecosystem. The data also corroborate and refines the population structure scenario of I. parvipinnis recently described using complementary phenotypic tags. [ABSTRACT FROM AUTHOR]

In this paper, we investigated composition and trait turnover among fish assemblages in reservoirs distributed across major Brazilian basins, in order to contrast taxonomic and functional turnover and to investigate their respective drivers. We investigated the hypothesis that reservoir assemblages present, on a continental scale, divergent species compositions but with a similar set of traits. Species lists and functional traits were compiled from 79 reservoirs located in the Amazon, São Francisco, Paraná and Atlantic basins. We observed considerable variation in species and trait composition among reservoirs, with higher intra-basin similarity. Taxonomic turnover ranged between 0 and 1 (0.44 ± 0.22 SD), and functional turnover between 0 and 0.91 (0.37 ± 0.19); functional turnover correlated positively with taxonomic turnover, but showed lower values. Observed functional turnover values did not differ from null expectations, indicating lack of functional convergence. We detected significant effects of basin, longitude, latitude and elevation on turnover values, and the presence of non-native species was associated with either homogenization or differentiation patterns. Our results indicated that fish composition is heterogeneous among impoundments, providing little support to the hypothesis that reservoir assemblages are homogenized on a continental scale. Species and trait composition probably respond to multiple spatial, environmental and biogeographic factors. [ABSTRACT FROM AUTHOR]

The present study provides a check list of elasmobranchs from the Paraná State coast, southern Brazil. Information from fish collections, literature data, field surveys and personal communications were included. Results indicated that 83 species from seven orders and 28 families were recorded. According to the results 51 species belonging to six orders and 17 families of sharks; and 32 species belonging to one order and eleven families of rays occur in this region. The most species-rich families were Carcharhinidae (14 species) and Arhynchobatidae (eight species). [ABSTRACT FROM AUTHOR]