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1.
Braz. j. biol ; 83: e250003, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339392

RESUMO

Abstract This study estimated the length-weight relationships of 16 fish species occurring close to the shores of sandy beaches along the lower Negro River basin, Brazilian Amazon. The specimens were captured for one day each month, in October to November 2016, early in the morning and early evening, using trawl net (20 m taken for standard length (SL - 0.1 cm precision) and total weight (TW - 0.01 g precision). The parameters a and b of the equation WT = a.LTb were estimated. The a values ranged from 0.0018 to 0.0226 and b values ranged from 2.5271 to 3.3244. This study also provides new data on of maximum lengths for six species, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa and Trachydoras microstomus, and new reports of the LWRs parameters of 15 fish species.


Resumo Este estudo estimou as relações comprimento-peso de 16 espécies de peixes que ocorrem às margens de praias arenosas ao longo da bacia do baixo Rio Negro, Amazônia brasileira. As espécies foram capturadas durante um dia de cada mês, de outubro a novembro de 2016, no início da manhã e no início da noite, usando rede de cerco (20 m de comprimento e 3,5 m de altura, 5 malha mm entre nós opostos). As medidas foram feitas para comprimento padrão (SL - precisão de 0,1 cm) e peso total (TW - precisão de 0,01 g). Os parâmetros a e b da equação WT = a.LTb foram estimados. Os valores de a variaram de 0,0018 a 0,0226 e os valores de b variaram de 2,5271 a 3,3244. Este estudo também fornece novos dados sobre comprimentos máximos para seis espécies, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa e Trachydoras microstomus, e novos reportes dos parâmetros da LWRs de 15 espécies de peixes.


Assuntos
Animais , Perciformes , Caraciformes , Characidae , Brasil , Rios
2.
Braz. J. Biol. ; 83: 1-5, 2023. mapas, tab
Artigo em Inglês | VETINDEX | ID: vti-765542

RESUMO

This study estimated the length–weight relationships of 16 fish species occurring close to the shores of sandy beaches along the lower Negro River basin, Brazilian Amazon. The specimens were captured for one day each month, in October to November 2016, early in the morning and early evening, using trawl net (20 m length and 3.5 m height, 5 mm mesh between opposite knots). Measurements were taken for standard length (SL 0.1 cm precision) and total weight (TW 0.01 g precision). The parameters a and b of the equation WT = a.LTb were estimated. The a values ranged from 0.0018 to 0.0226 and b values ranged from 2.5271 to 3.3244. This study also provides new data on of maximum lengths for six species, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa and Trachydoras microstomus, and new reports of the LWRs parameters of 15 fish species.(AU)


Este estudo estimou as relações comprimento-peso de 16 espécies de peixes que ocorrem às margens de praias arenosas ao longo da bacia do baixo Rio Negro, Amazônia brasileira. As espécies foram capturadas durante um dia de cada mês, de outubro a novembro de 2016, no início da manhã e no início da noite, usando rede de cerco (20 m de comprimento e 3,5 m de altura, 5 malha mm entre nós opostos). As medidas foram feitas para comprimento padrão (SL - precisão de 0,1 cm) e peso total (TW - precisão de 0,01 g). Os parâmetros a e b da equação WT = a.LTb foram estimados. Os valores de a variaram de 0,0018 a 0,0226 e os valores de b variaram de 2,5271 a 3,3244. Este estudo também fornece novos dados sobre comprimentos máximos para seis espécies, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa e Trachydoras microstomus, e novos reportes dos parâmetros da LWRs de 15 espécies de peixes.(AU)


Assuntos
Animais , Peixes/anatomia & histologia , Peixes/crescimento & desenvolvimento
3.
Parasitol Res ; 121(8): 2253-2262, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35624383

RESUMO

Hypostomus are abundant in Brazilian rivers and streams. In the Ivaí River, the loricariids represent 20.3% of the total species of the basin. Of these 13 species belong to Hypostomus. However, to date, there are no studies on these fish parasitic fauna. Thus, this research aimed to analyze the distribution of the parasitic infracommunity of six species of Hypostomus from the Ivaí River and investigate how the infracommunity is structured in these hosts. One hundred and twenty-eight fish were analyzed, belonging to six sympatric species of Hypostomus (Hypostomus hermanni, H. cochliodon, H. albopunctatus, H. regani, Hypostomus sp.1, and Hypostomus sp.2); of these, 92.9% were parasitized with at least one taxon, totaling 1478 specimens of parasites. The parasitic fauna was composed of the ectoparasites Trinigyrus anthus, T. carvalhoi, Unilatus unilatus (monogeneans), and Placobdella spp. (hirudinea), and the endoparasites Austrodiplostomum compactum (digenean) and Procamallanus annipetterae (nematode). The parasites exhibited similar patterns of infection in all hosts, including a low number of species, low diversity, and numerical dominance of a group of parasites. However, permutational multivariate analysis of variance (PERMANOVA) showed different parasite species compositions among the hosts. Hypostomus cochliodon and H. regani had the highest parasite richness, while Hypostomus sp.1 and Hypostomus sp.2 showed low abundance and intensity of parasitic infections. However, Hypostomus sp.1 showed the highest values of evenness, although the parasite composition in both species did not differ. The results presented herein contribute to increasing the knowledge about the parasitic fauna of Hypostomus spp. from the Ivaí River by presenting new hosts and locality records.


Assuntos
Peixes-Gato , Sanguessugas , Parasitos , Trematódeos , Animais , Brasil/epidemiologia , Peixes-Gato/parasitologia , Rios/parasitologia
5.
Environ Monit Assess ; 194(3): 227, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35218441

RESUMO

Long-term monitoring enables scientists and managers to track changes in the temporal and spatial distributions of fishes. Given the anthropogenic stressors affecting marine ecosystem health, there is a critical need for robust, comprehensive fish monitoring programs. Citizen science can serve as a meaningful, cost-effective strategy to survey fish communities. We compared data from 13,000 surveys collected over 21 years (1998-2019) by Reef Environmental Education Foundation (REEF) volunteer divers to a published compilation of Salish Sea ichthyofauna collected using an assortment of methods. Volunteer divers observed 138 of 261 recognized species in the Salish Sea, expanded the range of 18 species into additional Salish Sea sub-basins, and identified one species novel to the Salish Sea (Gibbonsia metzi - Striped Kelpfish). To identify Salish Sea fish species that are most suitable to be monitored by underwater visual census and to evaluate confidence in in situ identification, we developed a categorization system based on the likelihood of recreational divers and snorkelers encountering a given species, and on whether identification required a specimen in hand or could be classified to species visually (with or without a high-quality photograph). REEF divers encountered 62% (138 of 223) of the visually detectable species occurring in the region and 85% (102 of 120) of species most likely to be observed by recreational divers. Our findings show that citizen scientists provide valuable monitoring data for over half of the 261 marine and anadromous fish species known to occupy the Salish Sea, many of which are not routinely monitored otherwise.


Assuntos
Ecossistema , Monitoramento Ambiental , Animais , Monitoramento Ambiental/métodos , Peixes , Humanos , Voluntários
6.
Rev. peru. biol. (Impr.) ; 29(1): e21280, ene.-mar. 2022. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1377195

RESUMO

Resumen Este trabajo reporta la presencia inusual de especies de la familia Carangidae en los desembarcaderos de la provincia de Pisco (13.5° S), departamento de Ica, ocurridos durante el evento El Niño costero 2017. Se observaron 4 especies: Caranx caballus, Caranx caninus, Oligoplites saurus y Selene brevoortii capturadas con el arte de pesca "cortina agallera". Durante el periodo de El Niño costero 2017 en el área de estudio se registraron temperaturas superiores a los 26 °C y salinidades moderadamente elevadas (> 35.1 ups), condiciones que habrían favorecido el desplazamiento de estas especies, frecuentes en el norte del Perú, hacia latitudes superiores.


Abstract This work reports the unusual presence of species of the Carangidae family in Pisco province coast (13.5° S), department of Ica, which occurred during the El Niño costero 2017 event. Four species were observed: Caranx caballus, Caranx caninus, Oligoplites saurus y Selene brevoortii were captured with the "cortina agallera" fishing gear. During the El Niño costero 2017 in the study area, temperatures above 26 °C and moderately high salinities (> 35.1 ups) were recorded, conditions would have favored the displacement of these species, frequent in the north of Peru, towards higher latitudes.

7.
J Helminthol ; 96: e4, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34991737

RESUMO

The construction of dams causes several impacts on aquatic environments, altering the flow of rivers, environmental variables, and all biota present, including parasites. Little is known about how the parasitic community can be influenced in the long term by environmental changes. In this study, it was expected that the impacts caused by environmental disturbances will be directly reflected by the composition of the parasite populations. We evaluated the change in the structure of the Prochilodus lineatus endoparasite community between two periods sampled 15 years apart in the upper Paraná River floodplain. There was a significant difference in the weight-length relationship of P. lineatus between these periods and a total of 15 species of parasites were found: 11 species in Period 1 and nine species in Period 2 and five species occurred in both periods. The species richness and diversity were higher in Period 1, and we observed that the correlation of descriptors (richness, diversity and evenness) increased with fish length in this period. In both periods, digeneans numerically dominated the parasitic community, and we verified changes in the composition of parasites between periods. Both the host and the parasites were possibly affected by the environmental impacts resulting from the construction of dams over time, and it is noteworthy that complex life cycle parasites such as Digenea and Acanthocephala require intermediate hosts to complete their life cycle, and the population responds to fluctuations in the face of modified environments.


Assuntos
Acantocéfalos , Caraciformes , Parasitos , Trematódeos , Animais , Brasil , Rios
8.
Biodivers Data J ; 10: e65981, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35068977

RESUMO

BACKGROUND: The Barcode of Life initiative was originally motivated by the large number of species, taxonomic difficulties and the limited number of expert taxonomists. Colombia has 1,610 freshwater fish species and comprises the second largest diversity of this group in the world. As genetic information continues to be limited, we constructed a reference collection of DNA sequences of Colombian freshwater fishes deposited in the Ichthyology Collection of the University of Antioquia (CIUA), thus joining the multiple efforts that have been made in the country to contribute to the knowledge of genetic diversity in order to strengthen the inventories of biological collections and facilitate the solution of taxonomic issues in the future. NEW INFORMATION: This study contributes to the knowledge on the DNA barcodes and occurrence records of 96 species of Colombian freshwater fishes. Fifty-seven of the species represented in this dataset were already available in the Barcode Of Life Data System (BOLD System), while 39 correspond to new species to the BOLD System. Forty-nine specimens were collected in the Atrato River Basin and 708 in the Magdalena-Cauca asin during the period 2010-2020. Two species (Loricariichthysbrunneus (Hancock, 1828) and Poeciliasphenops Valenciennes, 1846) are considered exotic to the Atrato, Cauca and Magdalena Basins and four species (Oncorhynchusmykiss (Walbaum, 1792), Oreochromisniloticus (Linnaeus, 1758), Parachromisfriedrichsthalii (Heckel, 1840) and Xiphophorushelleri Heckel, 1848) are exotic to the Colombian hydrogeographic regions. All specimens are deposited in CIUA and have their DNA barcodes made publicly available in the BOLD online database. The geographical distribution dataset can be freely accessed through the Global Biodiversity Information Facility (GBIF).

9.
Sci Total Environ ; 807(Pt 2): 150987, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34656604

RESUMO

When the Fundão dam collapsed in Brazil, 50 million m3 of iron ore tailings were released into the Doce river, resulting in the world's largest mining disaster. The contaminated mud was transported 668 km downstream of the Doce river and reached the Atlantic Ocean 17 days after the collapse. Seven months later, there was evidence that the tailings had reached the largest and richest coral reef formation in the South Atlantic Ocean. This study provides the first description of species composition, abundance, and diversity patterns of fish assemblages in estuaries, coastal areas, and coral reefs affected by the rupture of the mining dam in the Doce river. A linear mixed model (GLMM) was used to evaluate the influence of salinity on fish abundance across estuarine and coastal ecosystems. In addition, based on functional traits related to habitat use and feeding habits, this study identified fish species suitable as bioindicators of the long-lasting effects of this major mining disaster. Bottom trawls were used to sample five estuaries and their respective coastal areas, and a visual census was employed to sample five reef areas, representing an impact gradient. A total of 269 species were recorded in all three habitats, but only seven were shared among them. The results showed lower similarity in assemblages among estuarine areas compared to the coastal and reef areas. Species composition among estuaries and reef ecosystems was more heterogeneous. In contrast, coastal habitats exhibited high homogeneity. Salinity had no statistically significant effect on fish abundance either in estuaries (p = 0.22) and along the coast (p = 0.14). Twelve fish species were identified as suitable bioindicators for evaluating the long-lasting effects of resuspension of contaminated sediments. These species are commonly found in the ecosystems under the influence of the disaster inhabiting potentially contaminated substrates and substrate-associated benthic preys.


Assuntos
Desastres , Ecossistema , Peixes/classificação , Mineração , Poluição da Água , Animais , Monitoramento Biológico , Brasil , Rios
10.
Braz. j. biol ; 82: e232868, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153458

RESUMO

Abstract The "piaussu", Megaleporinus macrocephalus is an anostomatid fish species native to the basin of the Paraguay River, in the Pantanal biome of western Brazil. However, this species has now been recorded in a number of other drainages, including those of the upper Paraná, Uruguay, Jacuí, Doce, Mucuri, and Paraíba do Sulrivers. This study presents two new records of the occurrence of M. macrocephalus, in the basins of the Itapecuru and Mearim rivers in the state of Maranhão, in the Brazilian Northeast. The piaussu is a large-bodied fish of commercial interest that is widely raised on fish farms, and its occurrence in the Itapecuru and Mearim rivers is likely the result of individuals escaping from fish tanks when they overflow during the rainy season. Morphological analyses and sequences of the Cytochrome Oxidase Subunit I (COI) gene confirmed the taxonomic identification of the specimens as M. macrocephalus. The COI sequences were 99.66% similar to those of M. macrocephalus deposited in the BOLDSystems database. These records extend the known distribution of M. macrocephalus to the basins of the Itapecuru and Mearim rivers in the Brazilian Northeast, highlighting a new case of introduction of exotic fish species into Brazilian river basins.


Resumo Megaleporinus macrocephalus é uma espécie de peixe anostomatídeo nativa da bacia do rio Paraguai, no bioma Pantanal do oeste do Brasil. No entanto, essa espécie já foi registrada em várias outras drenagens, incluindo as dos rios Alto Paraná, Uruguai, Jacuí, Doce, Mucuri e Paraíba do Sul. Este estudo apresenta dois novos registros da ocorrência de M. macrocephalus, nas bacias dos rios Itapecuru e Mearim, no estado do Maranhão, no nordeste brasileiro. O piaussu é um peixe de grande porte, de interesse comercial, amplamente criado em pisciculturas, e sua ocorrência nos rios Itapecuru e Mearim é provavelmente o resultado de indivíduos que escapam dos tanques quando transbordam durante a estação chuvosa. Análises morfológicas e sequências do gene da subunidade I do citocromo oxidase (COI) confirmaram a identificação taxonômica dos espécimes como M. macrocephalus. As sequências de COI foram 99,66% semelhantes às de M. macrocephalus depositadas no banco de dados BOLDSystems. Esses registros estendem a conhecida distribuição de M. macrocephalus às bacias dos rios Itapecuru e Mearim, no nordeste brasileiro, destacando um novo caso de introdução de espécies exóticas de peixes nas bacias hidrográficas brasileiras.


Assuntos
Humanos , Animais , Rios , Caraciformes/genética , Paraguai , Uruguai , Brasil
11.
Neotrop. ichthyol ; 20(1): e210091, 2022. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1365210

RESUMO

We describe the change in the fish community of the Porce River in Magdalena River Basin, Colombia, following the construction of the Porce III hydropower reservoir based on 13 years of monitoring data. The results show a clear reduction of the number of native species, which have been supplanted by colonizing non-native species, especially in the reservoir. Four native species detected prior to dam construction have apparently disappeared, but 12 new species were registered post-construction. We analyzed spatial changes in beta diversity in the aquatic environments surrounding the dam. The new environment generated by the reservoir presents a unique species composition and contributes significantly to the total beta diversity of the system. Altogether three distinct new fish assemblages emerged following reservoir formation and there are now six assemblages where there had previously been three. This dramatic change, already visible within a decade of construction, highlights just how strong of an impact dam construction has on habitats and how rapidly fish communities react in this hotspot for endemic fish diversity. Our findings demonstrate the importance of monitoring fish communities for revealing the impact of damming on river ecosystems and informs potential complementary fish diversity inventories elsewhere in the Magdalena River basin.(AU)


Describimos el cambio en la comunidad de peces del río Porce en la cuenca del río Magdalena en Colombia luego de la construcción del embalse hidroeléctrico Porce III con base en 13 años de datos de monitoreo. Los resultados mostraron una reducción de especies nativas y, el embalse ha sido colonizado por especies no nativas. A lo largo del monitoreo cuatro especies desaparecieron de las capturas, y se registró la aparición de 12 especies nuevas después de la construcción del embalse. Analizamos los cambios espaciales en la diversidad beta en los ambientes acuáticos que rodean la presa. El nuevo entorno generado por el embalse presenta una composición de especies única; en total, surgieron tres nuevos ensamblajes de peces distintos después de la formación del embalse y ahora hay seis ensamblajes. Este cambio, ya visible a una década de la construcción, resalta cuán fuerte es el impacto que tiene la construcción de presas en los hábitats y cuán rápido reaccionan las comunidades de peces. Nuestros hallazgos demuestran la importancia de monitorear las comunidades de peces para revelar el impacto de las represas en los ecosistemas fluviales, además permite complementar los inventarios de diversidad en la cuenca del río Magdalena.(AU)


Assuntos
Animais , Reservatórios de Água , Ecossistema , Monitoramento Ambiental , Biodiversidade , Peixes
12.
Braz. J. Biol. ; 82: 1-6, 2022. mapas, tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-33340

RESUMO

The "piaussu", Megaleporinus macrocephalus is an anostomatid fish species native to the basin of the Paraguay River, in the Pantanal biome of western Brazil. However, this species has now been recorded in a number of other drainages, including those of the upper Paraná, Uruguay, Jacuí, Doce, Mucuri, and Paraíba do Sulrivers. This study presents two new records of the occurrence of M. macrocephalus, in the basins of the Itapecuru and Mearim rivers in the state of Maranhão, in the Brazilian Northeast. The piaussu is a large-bodied fish of commercial interest that is widely raised on fish farms, and its occurrence in the Itapecuru and Mearim rivers is likely the result of individuals escaping from fish tanks when they overflow during the rainy season. Morphological analyses and sequences of the Cytochrome Oxidase Subunit I (COI) gene confirmed the taxonomic identification of the specimens as M. macrocephalus. The COI sequences were 99.66% similar to those of M. macrocephalus deposited in the BOLDSystems database. These records extend the known distribution of M. macrocephalus to the basins of the Itapecuru and Mearim rivers in the Brazilian Northeast, highlighting a new case of introduction of exotic fish species into Brazilian river basins.(AU)


Megaleporinus macrocephalus é uma espécie de peixe anostomatídeo nativa da bacia do rio Paraguai, no bioma Pantanal do oeste do Brasil. No entanto, essa espécie já foi registrada em várias outras drenagens, incluindo as dos rios Alto Paraná, Uruguai, Jacuí, Doce, Mucuri e Paraíba do Sul. Este estudo apresenta dois novos registros da ocorrência de M. macrocephalus, nas bacias dos rios Itapecuru e Mearim, no estado do Maranhão, no nordeste brasileiro. O piaussu é um peixe de grande porte, de interesse comercial, amplamente criado em pisciculturas, e sua ocorrência nos rios Itapecuru e Mearim é provavelmente o resultado de indivíduos que escapam dos tanques quando transbordam durante a estação chuvosa. Análises morfológicas e sequências do gene da subunidade I do citocromo oxidase (COI) confirmaram a identificação taxonômica dos espécimes como M. macrocephalus. As sequências de COI foram 99,66% semelhantes às de M. macrocephalus depositadas no banco de dados BOLDSystems. Esses registros estendem a conhecida distribuição de M. macrocephalus às bacias dos rios Itapecuru e Mearim, no nordeste brasileiro, destacando um novo caso de introdução de espécies exóticas de peixes nas bacias hidrográficas brasileiras.(AU)


Assuntos
Animais , Peixes/anatomia & histologia , Peixes/genética
13.
Rev. peru. biol. (Impr.) ; 28(spe): e21911, dic. 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1377178

RESUMO

Abstract This study presents an extensive review of published and unpublished occurrence records of fish species in the Loreto department. Located in the northeast of the country, Loreto is the most geographically extensive region in the Peruvian territory. Despite the increase in fish collections in Loreto in recent years, the ichthyofauna of this department needs to be more documented. Based on a database of scientific collections and bibliographic information, an updated checklist of the freshwater fishes from Loreto is presented. The results reveal a rich and diversified ichthyofauna, with 873 species distributed in 331 genera, 50 families and 15 orders. The main groups are Characiformes (42.6%), Siluriformes (34.8%), Gymnotiformes (8.6%) and Cichliformes (7.4%). Part of the ichthyofauna has restricted distribution for Loreto (4.7%). In addition, 9.0% of species from Loreto are used in fisheries. Meanwhile, 219 species (25%) were categorized according to the IUCN criteria where only six species (0.7%) are currently considered threatened species (CR, EN or VU). The results presented in this work indicate that this department needs more studies to know the biodiversity of fish, likewise, the information presented constitutes a contribution to the knowledge of fish diversity that would support environmental management actions and decision-making aimed at conserving one of the most diverse departments of Peru.


Resumen Este trabajo presenta una revisión de los registros de especies de peces, publicados y no publicados, del departamento de Loreto. Localizado al noreste del país, Loreto es el departamento más extenso del territorio peruano. A pesar del incremento en el número de las colectas de peces en Loreto en años recientes, la ictiofauna de este departamento necesita ser más documentada. Sustentado en los registros en bases de datos de colecciones científicas e información bibliográfica, se presenta una actualización de la lista de peces de agua dulce de Loreto. Los resultados revelaron una ictiofauna rica y diversificada, con 873 especies, distribuidas en 331 géneros, 50 familias y 15 órdenes. Los principales taxones fueron Characiformes (42.6%), Siluriformes (34.8%), Gymnotiformes (8.6%) y Cichliformes (7.4%). Parte de la ictiofauna tiene distribución restricta para Loreto (4.7%). Además, 9.0% de las especies son usadas en pesquerías de Loreto. Mientras tanto, 219 (25%) especies fueron categorizadas de acuerdo con los criterios de la IUCN, donde sólo seis especies (0.7%) son consideradas actualmente especies amenazadas (CR, EN o VU). Los resultados presentados en este trabajo señalan que este departamento necesita más estudios para conocer la biodiversidad de peces, así mismo, la información presentada constituye un aporte al conocimiento de la biodiversidad íctica que respaldarían las acciones de gestión ambiental y toma de decisiones destinados a conservar uno de los departamentos más diversos del Perú.

14.
Zookeys ; 1062: 177-201, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720621

RESUMO

San Pedro Mártir island is of high biological, ecological, and fishery importance and was declared a biosphere reserve in 2002. This island is the most oceanic in the Gulf of California, and information on its rocky reefs is scarce. The present study aimed to generate the first list of conspicuous invertebrate and fish species based on in situ observations and to examine the community structure of the shallow rocky reefs of the reserve. In addition, we estimated the ecological indicators of richness, abundance, Shannon diversity, and Pielou evenness to evaluate the conservation status of the biosphere reserve. Data were collected annually from 2007 to 2017 through 2,192 underwater SCUBA transects. A total of 35 species of invertebrates and 73 species of fish were recorded. Most of the species are widely distributed along the eastern Pacific. Overall, 64% of the species found in this study are commercially important, and 11 species have been listed as protected. The abundance of commercially important invertebrate species (i.e., the sea cucumber Isostichopusfuscus and the spiny oyster Spondyluslimbatus) is decreasing, while commercially important fish species have maintained their abundance with periods of increase. The ecological indicators and the abundance and size of the commercial species indicate that the reserve is in good condition while meeting its conservation objectives.

15.
Mar Pollut Bull ; 173(Pt B): 113142, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34801890

RESUMO

Karankadu mangrove situated along the Southeast coast of India is known for its unique and extreme species diversity and richness. Ecological functions of this mangrove comprise of nutrient cycling, coastal protection, fish fauna production and carbon sequestration besides providing livelihood to nearby coastal communities. The current study having assessed seasonal fluctuations of various Physico-chemical factors viz., rainfall, pH, surface water temperature, salinity, dissolved nutrients in the water and sediments, primary productivity and plant pigments (chlorophylls a,b,c) during the study period from July 2018 to June 2019, recorded a total of 29 species of zooplankton, 26 species of phytoplankton, and 19 species of fish with observed maximum density at summer and pre-monsoon period of the year. Relationship between the biotic and abiotic components of the ecosystem from the baseline data collected, was established through the statistical analysis performed.


Assuntos
Ecossistema , Plâncton , Animais , Monitoramento Ambiental , Estações do Ano , Água do Mar
16.
Tese em Português | VETTESES | ID: vtt-218451

RESUMO

O objetivo deste estudo foi caracterizar a composição da diversidade da ictiofauna dos campos alagados da comunidade da Chapada e do estuário do rio Tracuateua-Quatipuru. O estudo foi realizado no município de Tracuateua, localizado no Nordeste paraense, sendo o lócus da pesquisa na região dos campos naturais alagados, na comunidade da Chapada. Foram selecionados três pontos de amostragem, sendo dois dentro dos campos alagados e um na região estuarina do rio Tracuateua-Quatipuru. As coletas se deram entre os meses de setembro de 2019 a setembro de 2020 para contemplar os períodos seco e chuvoso. Foram coletados 1.293 indivíduos distribuídos em 14 ordens, 26 famílias e 44 espécies. As ordens mais abundantes foram Characiformes (31,4%), Siluriformes (29%) e Perciformes (16,6%). A maior densidade de indivíduos foi registrada no período chuvoso (N=662), e o maior número de espécies foi registrada no ponto 3 (S=27). O índice de Shannon foi maior no ponto 3 durante o período seco (H=2,3006). No entanto, a maior riqueza foi registrada nesse ponto durante o período chuvoso (d=3,5794). Conclui-se que o trabalho apresenta informações importantes sobre a ictiofauna local capaz de balizar futuras ações de manejo sustentável dos recursos naturais da região.


The aim of this study was to characterize the composition of ichthyofauna diversity in the flooded fields of the Chapada community and the estuary of the Tracuateua-Quatipuru river. The study was carried out in the municipality of Tracuateua, located in the Northeast of Pará, with the research locus in the region of flooded natural fields, in the community of Chapada. Three sampling points were selected, two within the flooded fields and one in the estuarine region of the Tracuateua-Quatipuru river. The collections took place between the months of september 2019 to september 2020 to cover the dry and rainy periods. A total of 1,293 individuals were collected, distributed in 14 orders, 26 families and 44 species. The most abundant orders were Characiformes (31.4%), Siluriformes (29%) and Perciformes (16.6%). The highest density of individuals was recorded in the rainy season (N=662), and the highest number of species was recorded in point 3 (S=27). The Shannon index was higher at point 3 during the dry period (H=2.3006). However, the greatest richness was recorded at this point during the rainy season (d=3.5794). It is concluded that the work presents important information about the local ichthyofauna capable of guiding future actions for the sustainable management of natural resources in the region.

17.
Forensic Sci Med Pathol ; 17(3): 517-521, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34106426

RESUMO

Amazonian's forensic experts usually experience considerable difficulties in the identification of drowned bodies rescued from the rivers of the Amazon basin, since they are frequently found skeletonized by the action of the cadaverous ichthyofauna. In these circumstances, especially when the soft tissues are completely absent, bones and teeth may represent the unique source of information for the identification of the body. This work reports a case of positive identification of a body skeletonized by scavenger ichthyofauna. The identification was performed by comparing computerized delineation of the dental characteristics of the cadaver with those observed in a smiling photograph of the victim. This report also highlights the ferocity of Cetopsis candiru (candiru cobra), Cetopsis coecutiens (candiru-açu) and Calophysus macropterus (piracatinga).


Assuntos
Afogamento , Sorriso , Cadáver , Odontologia Legal , Humanos , Rios
18.
B. Inst. Pesca ; 47: e621, 2021. mapas, tab
Artigo em Inglês | VETINDEX | ID: vti-765376

RESUMO

Studies on length-weight relationships are of great importance in fishery assessments. These studies are substantial to evaluate fish population dynamics, and in communion with the relative condition factor, could provide an estimation of potential acting environmental conditions. In this paper, we evaluated the length-weight relationship and relative condition factor of small sized fish species. Fish were sampled quarterly between the years 2012-2013 and 2018-2020 in lagoons and tributaries of Rosana and Taquaruçu reservoirs, located at the lower Paranapanema River basin, Brazil. The standard length (SL) in millimeters and weight (W) in grams were measured, and the length-weight relationship was calculated using linear regression analysis (W = log (a) + b log (SL)). After, the relative condition factor (Kn) was calculated from the expression We = a.SLb. Thus, the length-weight relationships of 31 species were calculated in each environment considered, giving rise to 74 population allometric coefficients (b) and relative condition factors (Kn). As result, 24 bcoefficients were concentrated between 2.5 and 3.5 and seven were out of the confidence interval, while the 74 Kn values demonstrated close to the central mean and not statistical different. Our results are relevant to the conservation of fish fauna, improving knowledge regarding small-sized fish and those living environment.(AU)


Estudos sobre relações peso-comprimento são de grande importância nas avaliações de pesca. Esses estudos são substanciais para avaliar a dinâmica populacional de peixes e, em comunhão com a aplicação do fator de condição relativo, podem fornecer uma estimativa das condições ambientais potencialmente atuantes. Neste estudo, avaliamos a relação peso-comprimento e o fator de condição relativo de espécies de pequeno porte. Os peixes foram coletados trimestralmente entre os anos de 2012-2013 e 2018-2020 em lagoas e tributários dos reservatórios de Rosana e Taquaruçu, bacia do Baixo Rio Paranapanema, Brasil. O comprimento padrão (SL) em milímetros e o peso (W) em gramas foram mensurados, e a relação peso-comprimento foi calculada por meio de regressão linear (W = log (a) + b log (SL)). Em seguida, o fator de condição relativo (Kn) foi calculado a partir da expressão We = a.SLb. Assim, as relações peso-comprimento de 31 espécies foram mensuradas em cada ambiente estudado, dando origem a 74 coeficientes alométricos (b) e fatores de condição relativo (Kn) populacionais. Como resultado, 24 coeficientes b se concentraram entre 2,5 e 3,5 e sete fora deste intervalo de confiança, enquanto os valores de 74 Kn se mostraram próximos à média central e não estatisticamente diferentes. Nossos resultados são relevantes para a conservação da ictiofauna, contribuindo para o conhecimento sobre os peixes de pequeno porte e seu ambiente de vida.(AU)


Assuntos
Animais , Peixes/anatomia & histologia , Pesos e Medidas Corporais/veterinária
19.
Tese em Português | VETTESES | ID: vtt-218646

RESUMO

Acredita-se que os manguezais sejam indispensáveis para a produtividade das pescarias costeiras, atuando como áreas de berçário e desempenhando papel significante na ecologia de várias espécies de peixes tropicais de importância econômica e ecológica. Contudo, essas florestas continuam enfrentando diferentes processos de degradação e ainda que o uso dos manguezais pela ictiofauna seja bem documentado, raramente essa abordagem é usada para analisar a relação entre o estado de conservação do habitat e a pesca. Neste contexto, o objetivo deste trabalho é avaliar a influência do estado de conservação dos manguezais sobre as populações de peixes com interesse ecológico e econômico do município de Acaraú CE, bem como caracterizar as espécies associadas a esses ambientes. Para isso, foram realizadas amostragens bimestrais, entre os meses de julho/2019 a maio/2020. As coletas foram realizadas utilizando tarrafas, sempre durante a baixa-mar de sizígia. Todos os peixes capturados foram colocados em sacos plásticos previamente identificados com os dados de cada canal amostrado e armazenados em caixas de isopor com gelo para transporte até o laboratório, onde foram identificados, medidos e dissecados. Ao todo, foram coletados 1.713 indivíduos, distribuídos em 37 espécies, 27 famílias, 14 ordens e 2 classes. As famílias Gerreidae e Lutjanidae foram as mais representativas no estuário, compreendendo juntas 58,14% das amostragens. Mais de 80% das espécies amostradas nos bosques de mangue são de interesse econômico para Acaraú. Espécies ameaçadas de extinção também foram registradas, tais como: Megalops atlanticus, Hippocampus erectus, Lutjanus analis, Lutjanus jocu e Mycteroperca bonaci. A ictiofauna apresentou variações em sua composição de acordo com o estado de conservação dos quatro bosques de mangue estudados, principalmente na abundância de indivíduos. Porém, não houve diferenças sazonais na composição da ictiofauna e das variáveis ambientais. A salinidade e o Índice de Intensidade do Desenvolvimento da Paisagem (IDP) foram as principais variáveis ambientais responsáveis pela distribuição e composição da ictiofauna. As espécies Eucinostomus argenteus, Lutjanus jocu e Lutjanus alexandrei foram dominantes no estuário durante todo período amostral, compreendendo juntas 39,98% das amostragens totais. Para as categorias tróficas, a maior representatividade foi das espécies Piscívoras/Zoobentívoros, compreendendo 48,56% das amostragens. Enquanto nas categorias tróficas, a maior representatividade foi das espécies Piscívoras/Zoobentívoras, compreendendo 48,56% das amostragens. Não houve diferenças sazonais e espaciais significativas entre a dominância de espécies e as categorias ecológicas e tróficas. Somente as espécies Batrachoides surinamensis, Lile piquitinga, Lycengraulis batesii, Sphoeroides testudineus e Strongylura timucu apresentaram gônadas aptas a reprodução, compreendendo 7,19% das amostragens. Contudo, aproximadamente 92% da ictiofauna foi composta por indivíduos jovens que utilizam a ictiofauna como áreas de berçário. Os quatro bosques de mangue estudados apresentaram condições propícias ao crescimento e estado de higidez das espécies avaliadas. Porém, o bosque de mangue em Arpoeiras, com os menores valores de IDP ofereceram melhores condições que os bosques de mangue mais degradados.


Mangroves are believed to be indispensable for coastal fisheries productivity, acting as nursery areas and playing a significant role in the ecology of several species of tropical fish of economic and ecological importance. However, these forests continue to face different degradation processes and although the use of mangroves by ichthyofauna is well documented, this approach is rarely used to analyze the relationship between habitat conservation status and fisheries. In this context, the objective of this work is to evaluate the influence of the mangrove conservation status on fish populations with ecological and economic interest in the municipality of Acaraú - CE, as well as to characterize the species associated with these environments. For this, bimonthly samplings were carried out, between the months of July/2019 to May/2020. The collections were carried out using nets, always during the low tide of spring. All captured fish were placed in plastic bags previously identified with the data for each sampled channel and stored in polystyrene boxes with ice for transport to the laboratory, where they were identified, measured and dissected. In all, 1.713 individuals were collected, distributed in 37 species, 27 families, 14 orders and 2 classes. The Gerreidae and Lutjanidae families were the most representative in the estuary, comprising together 58.14% of the samples. More than 80% of the species sampled in the mangrove forests are of economic interest to Acaraú. Endangered species have also been recorded, such as: Megalops atlanticus, Hippocampus erectus, Lutjanus analis, Lutjanus jocu and Mycteroperca bonaci. The ichthyofauna showed variations in its composition according to the conservation status of the four mangrove forests studied, mainly in the abundance of individuals. However, there were no seasonal differences in the composition of the ichthyofauna and environmental variables. Salinity and the Landscape Development Intensity Index (IDP) were the main environmental variables responsible for the distribution and composition of the ichthyofauna. The species Eucinostomus argenteus, Lutjanus jocu and Lutjanus alexandrei were dominant in the estuary throughout the sampling period, comprising together 39.98% of the total samples. For trophic categories, the largest representation was Piscivorous/Zoobentivorous species, comprising 48.56% of the samples. While in the trophic categories, the largest representativeness was Piscivorous/Zoobentivorous species, comprising 48.56% of the samples. There were no significant seasonal and spatial differences between species dominance and ecological and trophic categories. Only the species Batrachoides surinamensis, Lile piquitinga, Lycengraulis batesii, Sphoeroides testudineus and Strongylura timucu presented gonads capable of reproduction, comprising 7.19% of the samples. However, approximately 92% of the ichthyofauna was composed of young individuals who use the ichthyofauna as nursery areas. The four mangrove forests studied showed favorable conditions for growth and health status of the species evaluated. However, the mangrove forest in Arpoeiras, with the lowest IDP values, offered better conditions than the more degraded mangrove forests.

20.
Biodivers Data J ; 9: e63945, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33732033

RESUMO

BACKGROUND: The Xisha Islands are composed of the Yongle Islands and the Xuande Islands in Hainan Province, China. It has one of the highest species diversity in the world and is also a typical oceanic distribution area of coral reefs globally. The ichthyofauna of the Xisha Islands were recorded by underwater visual census in May 2019 and July 2020. The survey data were combined with previous records of species into the checklist of the Xisha Islands presented herein. A total of 691 species, belonging to 24 orders and 97 families, was recorded. The major families were Labridae, Pomacentridae, Serranidae, Chaetodontidae, Hexanchidae, Lutjanidae, Scaridae, Gobiidae, Scorpaenidae and Carangidae. In this study, the Coral Fish iversity Index (CFDI) of six families (Chaetodontidae, Pomacanthidae, Pomacentridae, Labridae, Scaridae and Acanthuridae) was 229, indicating 756 coral fishes. In terms of the IUCN Red List, one species is Critically Endangered (Glyphis gangeticus), six species are Endangered (Stegostoma fasciatum, Aetomylaeus maculatus, Aetomylaeus vespertilio, Epinephelus akaara, Cheilinusundulatus sp. and Xiphias gladius), 16 species are Vulnerable, and 13 species are Near Threatened in the Xisha Archipelago, so conservation should be strengthened in this area in the future. NEW INFORMATION: One species is a new record for China (Dischistodus pseudochrysopoecilus) and 23 species are newly found in the Xisha Islands.

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