79 research outputs found
Rendimento por recruta do tucunaré Cichla monoculus capturado no Lago Grande de Manacapuru
We evaluated the stock of peacock bass Cichla monoculus caught by a small-scale fishing fleet in Lago Grande at Manacapuru. The database was constructed by monthly samplings of 200 fish between February 2007 and January 2008. We measured the total length (cm) and total weight (gr) of each fish. We employed previously estimated growth parameters to run a yield per recruit model and analyse scenarios changing the values of the age of the first catch (Tc), natural mortality (M), and fishing mortality (F). Our model indicated an occurrence of overfishing because the fishing effort applied to catch peacock in Lago Grande at Manacapuru is greater than that associated with the maximum sustainable yield. In addition, the actual size of the first catch is almost half of the estimated value. Although there are difficulties in enforcing a minimum size of the catch, our results show that an increase in the size of the first catch to at least 25 cm would be a good strategy for management of this fishery
ESTRUTURA DE ASSEMBLÉIAS DE PEIXES EM UMA ÁREA DE EXPLORAÇÃO PETROLÍFERA NA AMAZÔNIA (BACIA DO RIO URUCU, AMAZONAS, BRASIL)
Na Amazônia há uma forte pressão ambiental causada por diversas atividades, dentre elas a exploração de minérios como petróleo e ouro. Rios desta região são alterados físico-química e biologicamente por serem os principais coletores dos contaminantes produzidos pela atividade humana. O objetivo deste trabalho foi caracterizar as assembléias de peixes do rio Urucu nas proximidades de áreas portuárias de uma base de exploração de petróleo e gás natural, sendo estas possivelmente impactadas por esta atividade explorativa. As coletas foram realizadas nos períodos de cheia e seca, em seis pontos: jusante do porto Evandro1 (PJE1), jusante do porto Evandro2 (PJE2), porto Evandro2 (PPE2), montante do porto Evandro2 (PME2), jusante do porto Urucu (PJU) e montante do porto Urucu (Pcontrole), em um trecho de 94,5 Km do rio Urucu, Coari / Amazonas / Brasil. Na cheia, foram coletados 489 exemplares e na seca, 439; sendo distribuídos em 82 espécies, com maior representatividade de Characiformes seguido dos Siluriformes. A maior e menor abundância foram encontradas no PJE1 na cheia (n = 122) e no Pcontrole na seca (n = 32), respectivamente. A maior e a menor riqueza, respectivamente, foram encontradas no PJE1 na cheia e Pcontrole na seca. O PJU e o PJE1 apresentaram-se mais uniformes na seca e o PJU menos na cheia. A piranha Serrasalmus rhombeus foi a espécie de maior abundância e freqüência de ocorrência quando comparada às outras espécies. As assembléias de peixes do trecho estudado em ambos os períodos do ciclo hidrológico, não foram alteradas pela atividade portuária local. Todavia, o intenso tráfego de balsas na área pode promover mudanças nas margens do rio, resultando em impactos de baixa magnitude, porém cumulativos, que podem gerar efeitos somente detectados com estudos a médio e longo prazo.Palavras-chave: ecologia, ictiofauna, impacto Ambiental, Amazônia, petróleo.ABSTRACTStructure of the assemblage of fish in an area of oil exploration in the Amazon (river basin Urucu, Amazonas, Brazil)In the Amazon there is a strong environmental pressure caused by various activities, including the exploitation of gold and oil. Rivers of this region are main collectors of contaminants produced by human activity, so their physic-chemical and biological characteristics are changed. The objective of this study was to characterize the fish assemblages of River Urucu, close of port areas at the exploitation’s basis of oil and natural gas, which one could be impacted by this activity. The samples were made in low and high water level in six points: downstream port Evandro1 (PJE1), downstream port Evandro2 (PJE2), port Evandro2 (PPE2), amount port Evandro2 (PME2), downstream port Urucu (PJU) and amount port Urucu (Pcontrole) in a stretch of 94.5 km of River Urucu, Coari / Amazon / Brazil. In wet season, 489 individuals were captured and in the dry season, 439; belonging to 82 species, with Characiformes as the most representative order followed by Siluriformes. The highest and lowest abundance was found in PJE1 in full (n = 122) and in dry Pcontrole (n = 32), respectively. The highest and lowest wealth, respectively, were found in PJE1 in the flood and drought in Pcontrole. The PJU and PJE1 had become more uniform at least in dry and PJU full. The piranha Serrasalmus rhombeus had the higher frequency of occurrence and abundance than all the other species. The fish assemblage of words studied in both periods of the hydrological cycle, were not altered by the local port activity. However, the heavy traffic of barges in the area can promote changes in the river, resulting in impacts of low, but cumulative, effects that can generate only detected with studies in the medium and long term.Key-words: ecology, ichthyofauna, environmental impact, Amazon, oil
Dinâmica espacial da pesca comercial no médio rio negro: Intensidade de explotação por áreas de pesca
In the middle Negro River, there have been several conflicts between the different fishing modalities due to the differential use of the fishing resource and the dispute over the same fishing areas. In this way, the spatial dynamics of commercial fishing in the municipality of Barcelos in the middle Negro River were analyzed, aiming to identify the locations used in the fisheries that may have different potentials and demand different actions. Information was collected from commercial fisher regarding the location of fishing sites and the frequency of use during high and low water periods. The geographic coordinates were identified with Q-Gis software and later submitted to a kernel-intensity technique. Eight fishing sites were used in commercial fisheries in Barcelos. In both hydrological periods, fishing occurred with a greater intensity in the Demeni River. Its waters change from light to white throughout the year, and there are several marginal areas that could serve as nurseries for various species of fish. Possibly, in this environment, there is a greater probability of conflicts occurring between the different resource users since this river is also exploited by recreational and subsistence fishers. This result shows that the spatial dynamics of fisheries can be truly important for management proposals. © 2019, Instytut Technologii Drewna. All rights reserved
AVALIAÇÃO DA PESCA COMERCIAL DESEMBARCADA EM DUAS CIDADES LOCALIZADAS NO RIO SOLIMÕES – AMAZONAS
The commercial fishing is an activity of great importance at the Amazon basin. It is subject to seasonal climatic, cultural and economic influences, which could be different by region into this huge basin. The commercial fisheries of Benjamin Constant and Iranduba were studied, aiming to evaluate the regional differences of the fisheries in the Amazon basin. The data were collected in 2012 at the main landing sites of both municipalities. The common name of the fish landed, catch per species (kg), fishing effort, fishing grounds, fishing gear and vessels used were registered. The largest variety of fish caught was recorded in Benjamin Constant, but Iranduba obtained the highest total landing. The pacús (Mylossoma spp.; Metynnis spp.; Myleus spp.) and acarí-bodó (Pterygoplichthys pardalis) were the most landed at Benjamin Constant. The aracú (Schizodon fasciatus) and curimatã (Prochilodus nigricans) were the most important species in the landings of Iranduba. In general, the production was higher during the falling water season. The rivers and lakes were the most exploited environments and the gillnet was most used equipment. The Catch per Unit Effort (CPUE) varied from 10.2 to 288.6 kg/fisher.day, with high averages in the falling-water period of the rivers. The motorized canoe was the most used vessel in the fisheries. The variations observed in the fisheries indicate the diversity of fishing in the Amazon. This diversity needs to be taken into account when developing fisheries management strategies, to avoid the development of generalist policies that are ineffective to reach the sustainability of fish stocks.Keywords: inland fisheries; geographical distribution of fisheries; Amazonia.A pesca comercial é uma atividade de elevada importância na bacia Amazônica e está sujeita a influências sazonais, culturais e econômicas que variam conforme a região. Dessa forma as pescarias comerciais de Benjamin Constant e Iranduba foram estudadas, visando avaliar as diferenças regionais das pescarias no Amazonas. Os dados foram coletados em 2012 nos principais locais de desembarque dos municípios. Foram registrados o nome comum dos peixes desembarcados, a captura por espécie (kg), esforço de pesca, ambientes explotados, os apetrechos e as embarcações utilizadas. A maior variedade de peixes capturados foi registrada em Benjamin Constant, porém Iranduba obteve maior desembarque. Os pacús (Mylossoma spp.; Metynnis spp.; Myleus spp.) e o acarí-bodó (Pterygoplichthys pardalis) foram os mais desembarcados em Benjamin Constant. O aracú (Schizodon fasciatus) e a curimatã (Prochilodus nigricans) foram as espécies mais importantes nos desembarques de Iranduba. No geral a produção foi maior durante o período de vazante dos rios. Os rios e lagos foram os ambientes mais explotados e a malhadeira o apetrecho mais utilizado. A Captura por Unidade de Esforço (CPUE) variou entre 10,2 e 288,6 kg/homem.dia com médias elevadas no período de vazante dos rios. A canoa motorizada foi a embarcação mais utilizada nas pescarias. As variações observadas nas pescarias indicam a diversidade da pesca na Amazônia. Essa diversidade precisa ser levada em consideração ao se desenvolver estratégias de manejo pesqueiro, para que sejam evitadas políticas generalistas ineficazes para a sustentabilidade dos estoques pesqueiros.Palavras-chave: pesca interior, distribuição geográfica da pesca, Amazônia
Amazon commercial fishing dynamics: a space macroscale analysis on fishing variables/ A dinâmica da pesca comercial amazônica: uma análise em macroescala espacial sobre variáveis da pesca
The landscape and the dynamics of seasonal flooding should be considered in the development of fishery management measures in the Amazon, as these factors determine the distribution and ecology of fishery resources and consequently the behavior of fisherman and fishery. In this context, the spatial dynamics of commercial fishing in the upper and lower reaches of the Solimões River were analyzed and the hypothesis that fishing is homogeneously developed by the Amazonian landscape was discussed. Catch data, number of fishers per trip, duration of fisheries and fishing locations were collected in 2012 at the main landing centers of the municipalities of Benjamin Constant and Iranduba. The geographical coordinates of fishing locations were recorded in 2018 using a hydrographic map of municipalities, a list of fishing locations documented in 2012 and the help of fishermen. The spatialization of fishery information was performed by municipality, by fishing location and by river regime period using the QGIS software (2.18). Thirty-two fishing sites were identified in the municipalities. The fishermen operated within a 175 km radius of Benjamin Constant during both periods of the river regime. In Iranduba the area of operation was 28 km in high water and 35 km in low water. In Benjamin Constant the Solimões River recorded the highest catches in both periods. In Iranduba the Iranduba coast and Manaquiri beach recorded the highest catches during periods of high and low waters, respectively. In Benjamin Constant the highest yields were recorded in the 35 km zone far from the municipal headquarters in both periods. While in Iranduba, in the high water period the highest yield was recorded in locations closer to the municipal headquarters than in the low water period. With the analysis of the spatial dynamics of commercial fishing we reject the hypothesis that fishing is homogeneously distributed throughout the Amazonian landscape and we propose to consider the spatial aspects of this activity in management systems
ÍNDICE DE INTEGRIDADE BIÓTICA UTILIZANDO ASSEMBLEIAS DE PEIXES DA REGIÃO NEOTROPICAL
Environmental impacts, natural or anthropogenic, are able to modifying the biotic integrity that is defined as capacity of the environment to maintain a balanced, integrated and adapted community, in which, the conditions biological and ecological are compared with community of a region without environmental impact. These conditions of impacts are measured by environmental quality index, among wich, Index of Biotic Integrity (IBI). The adaptations of index require the use of metrics that better represent the biological and ecological characteristics of the region. In this way, the purpose of the study was to present the use of metrics in the IIB adaptation for Neotropical region, considering the ichthyofauna as object. The literature to showed the use of adaptations for different aquatic environments, as Brazil, Mexico, Venezuela, Argentina and Costa Rica. The orders Characiformes and Siluriformes were utilized often in the studies, beyond the ecological indexes, abundance of individuals and trophic categories. The Gymnotiformes order although have been few used, can be promising for future adaptations. Beside the selections of metrics, the choose of referenece place for IBI comparation is also a constant difficulty for researchers. Keywords: environmental quality; multimetric indices; metric seletion; Neotropical region.Os impactos ambientais, sejam eles de natureza antrópica ou natural, são capazes de modificar a integridade biótica conceituada como a capacidade de um ambiente em manter uma comunidade de organismos balanceada, integrada e adaptada, nas quais, as condições biológicas e ecológicas são comparáveis com a comunidade de organismos de uma região sem impacto ambiental. Essas condições de impactos são mensuradas pelo uso de índices de qualidade do ambiente, dentre eles, o Índice de Integridade Biótica (IIB). A adaptação do índice requer o uso de métricas que melhor represente as características biológicas e ecológicas da região, porém nem sempre é simples escolher métricas representativas, exigindo um esforço do pesquisador e conhecimento da região. Diante disso, o objetivo deste trabalho de revisão foi apresentar o uso das métricas nas adaptações do IIB para a região Neotropical, considerando o uso da ictiofauna. Foram encontradas adaptações para diferentes ambientes aquáticos no Brasil, México, Venezuela, Argentina e Costa Rica. As ordens Characiformes e Siluriformes foram utilizadas frequentemente nos estudos, além de índices ecológicos, abundância de indivíduos e categorias tróficas. A ordem Gymnotiformes apesar de ter sido pouco utilizada, pode ser promissora para as adaptações futuras. Além da seleção de métricas, a escolha de pontos de referências que permitem comparações do IIB é também uma constante dificuldade encontrada pelos pesquisadores.Palavras-chaves: qualidade ambiental, índices multimétricos, seleção de métricas, região Neotropical
A PESCA ILEGAL DO TAMBAQUI NOS RIOS NEGRO, SOLIMÕES E AMAZONAS: UMA ANÁLISE DOS EFEITOS DA LEI DO DEFESO
Due to the decline in fish stocks in Brazil, mainly in the Amazon Basin, the Closed Fishing Season Law was implemented to help fisheries recover and protect fish habitat. Tambaqui (Colossoma macropomum) is one of the main overexploited fish species and there is concern about its decline in many Amazonian rivers. Therefore, in order to investigate the effectiveness of the Closed Fishing Season Law as it applies to tambaqui, seizure data compiled by IBAMA (Brazilian Institute of Environmental Protection) was analyzed for the period 1993 to 2012 (20 years) for the Negro, Solimões and Amazonas rivers. Although the results of this study showed variations in the volume of tambaqui seizures among the three different rivers analyzed over a 20-year period, these variations were small in comparison to the differences found between the 10-year periods before and after implementation of the Closed Fishing Season Law. Overall, there was a 24.4% decrease in the volume of tambaqui seized after implementation of the Law, which can be attributed to a number of possible reasons: 1) reduction of tambaqui stocks in the area of study; 2) occurrence of great floods and dry periods influenced by the natural phenomena El Niño and La Niña, which strongly affected fish stocks in 2002-2003 and 2009, respectively; 3) poor enforcement of regulations, due to reductions in IBAMA personnel and; 4) difficult to patrol such a large area, including many remote locations. However, notwithstanding the noted overall decrease, the results suggest that implementation of the Closed Fishing Season Law with its corresponding compensation payments to fishers did not end up dramatically improving the protection of tambaqui stocks and may have even encouraged more people to enter into the fishery to benefit from the payments. Keywords: Fishery stocks; fisheries; closed season compensation.Com o declínio dos estoques pesqueiros no Brasil, sobretudo na bacia Amazônica, foi criada a Lei do Defeso para auxiliar na recuperação dos estoques pesqueiros e na proteção de seus ambientes. O tambaqui (Colossoma macropomum) é uma das espécies de peixes mais sobreexplotada, onde já se reconhece a sua diminuição em muitos rios da Amazônia. Sendo assim, com o foco de investigar a eficácia do emprego da Lei do Defeso e sua aplicabilidade na defesa do tambaqui, dados das apreensões registradas pelo IBAMA (Instituto Brasileiro do Meio Ambiente) foram analisados para o período de 1993 a 2012 (20 anos), ocorridas nos rios Negro, Solimões e Amazonas. Os resultados mostraram que incidiram variações no número de apreensões de tambaquis entre os diferentes rios estudados durante o período de 20 anos, mas essas variações foram fracas, quando comparadas aos períodos de 10 anos antes e após a criação da Lei do Defeso. No entanto, foi registrado também, uma diminuição de 24,4% no número de infrações após a implementação da referida Lei, o que pode ser atribuído a várias possibilidades: 1) diminuição dos estoques da espécie na área do estudo; 2) ocorrência de grandes cheias e secas influenciadas por fenômenos naturais como o El Niño e a La Niña, que impactaram fortemente os estoques de peixes nos períodos de 2002-2003 e 2009, respectivamente; 3) reduzido efetivo de pessoal fiscalizador, em virtude da diminuição do efetivo de pessoal no IBAMA; e 4) dificuldades em fiscalizar regiões muito extensas, incluindo os locais remotos. Sendo assim, mesmo com a perceptível queda no número de apreensões de tambaqui na região do estudo, os resultados sugerem que o emprego da Lei do Defeso e do seu referido seguro para os pescadores, não alcançaram a finalidade desejada, e ainda, podem estar influenciando negativamente na sustentabilidade dos estoques de tambaquis da região, principalmente pelo incentivo ao ingresso de novos pescadores em virtude da oferta do seguro.Palavras-chave: Estoque pesqueiro, pescarias, seguro defeso
A PESCA COMERCIAL NO BAIXO RIO SOLIMÕES: UMA ANÁLISE DOS DESEMBARQUES DE MANACAPURU/AM
Commercial fishing is a high importance activity at the lower stretch of the Solimões river, and the municipality of Manacapuru is considered the main fishing landing center at this region. Fish landing information in the municipality of Manacapuru/AM in the year 2012 was analyzed to describe the fishery production, species composition and fishing grounds taking into account the variations related to the river regime. There were 1.356 fish landings and the average monthly landed fish was 117.93 ± 94.92 t. A total of 39 fish species were identified in commercial fishing, and the most landed (t) were jaraquis (Semaprochilodus spp. = 23.67%), pacus (Mylossoma spp., Myleus spp., Metynnis spp. = 22.19%), curimatã (Prochilodus nigricans = 17.69%), sardinha (Triportheus spp. = 12.01%) and matrinxã (Brycon amazonicus = 3.78%) representing 79% of the total fish caught. Redinha and malhadeira (97.51%) were the most used appliances. The rivers and lakes were the most explored environments throughout the year and contributed to the higher production in the landings. CPUE ranged from 14.73 ± 10.45 to 103.57 ± 185.83 kg/man.day throughout the year. CPUE peaks were recorded in flood periods in January and river ebb in August. The results indicate the high participation of migratory Characiformes in the fishery production of this region and the importance of the variation of the level of the Solimões river, which influences the composition of species, the use of capture sites and the relationships between species and environment.Keywords: Inland fishing; catch composition; Manacapuru; Amazon.A pesca comercial é uma atividade de elevada importância no trecho inferior do rio Solimões, sendo o município de Manacapuru considerado como o principal centro de desembarque pesqueiro da região. Os dados de desembarques de pescado no município de Manacapuru/AM no ano de 2012 foram analisados para descrever produção pesqueira, composição de espécies, locais de captura levando em consideração as variações relacionadas ao regime fluvial. Foram registrados 1.356 desembarques e a média mensal de pescado desembarcado foi de 117,93 ± 94,92 t. Foram identificadas 39 espécies de peixes nas pescarias sendo que jaraquis (Semaprochilodus spp. = 23,67 %), pacus (Mylossoma spp., Myleus spp., Metynnis spp. = 22,19%), curimatã (Prochilodus nigricans = 17,69 %), sardinhas (Triportheus spp. = 12,01%) e matrinxã (Brycon amazonicus = 3,78%) representaram 79% do total de pescado capturado. Redinha e malhadeira (97,51%) foram os aparelhos mais usados. Os rios e lagos foram os ambientes mais explorados ao longo do ano e contribuíram com a maior produção nos desembarques. A CPUE variou de 14,73 ± 10,45 a 103,57 ± 185,83 kg/homem.dia ao longo do ano. Foram registrados picos de CPUE nos períodos de enchente, em janeiro, e vazante, em agosto. Os resultados indicam a alta participação de Characiformes migradores na produção pesqueira dessa região e a importância da da variação do nível do rio Solimões, que influencia a composição de espécies, a utilização dos locais de captura e as relações entre espécies e ambiente.Palavras chave: pesca interior, composição de captura, Manacapuru, Amazônia
Meat of Tambaqui from fish farming leads the popular preference when compared to wild specimens (Rondônia - Brasil) / A carne de Tambaqui de piscicultura lidera a preferencia popular quando comparada aos especimes selvagens (Rondônia - Brasil)
The purpose of this paper was evaluate the palatability of the meat of tambaqui of different ages and environments, both from natural and cultivated systems. In order to carry out the consumers’ acceptability test concerning the tambaqui meat from different feeding, 14 wild fish and 14 cultivated ones were used, with average weight ranging from 0.8 to 8.5 kg, already killed, cut and fresh. The samples were separated according to the environment (wild and cultivated), stored in thermal box and processed as standard fried ribs. The total of 200 untrained tasters of both genders was consulted, with the intention of finding the common public’s opinion. The evaluated items were: flavor, color, smell and texture. The samples from pisciculture obtained better acceptability results regarding young fish’s meat (63.5%), and the adult’s (78.0%), as compared to the same age groups for the natural environment fish with 49.7% and 61.0% of the total evaluated, respectively. Thus, the sensorial analysis demonstrated a greater preference for cultivated tambaqui’s meat, with emphasis on the items flavor and texture, which can be attributed to feeding quality (fish food with 28% of crude protein) and husbandry employed in the farming syste
First environmental DNA (eDNA) record of central Amazon in a floodplain lake: extraction method selection and validation / Primeiro registro de DNA ambiental (eDNA) da Amazônia central em um lago de várzea: seleção e validação de método de extração
In recent years, environmental DNA (eDNA) has emerged as an effective method for detecting aquatic organisms. The current study tested a method of DNA extraction from water samples from Central Amazonian floodplain lake. Water collections were performed in a floodplain lake on Paciência Island, on the Solimões River (Amazon Basin, Brazil) during the high water period. Seven commercial DNA extraction methods/kits were tested with samples collected from Lake Cacau. After quantification, eDNA samples were amplified with 12S and 16S mitochondrial gene universal primers. The DNeasy Blood & Tissue kit (Qiagen), with modifications developed during the current study (adapt 03), gave the best overall result showing expected gene amplification, and intense agarose gel banding. eDNA concentrations ranged from 0.00 to 22.90 ng/µL for the other methods, with either lower intensity of the amplicon size to target gene correspondence when compared to that obtained with the DNeasy Blood & Tissue kit adapt 03 method, or there was an absence of amplification.The concentration of eDNA extracted from the lake sample was 2.68ng/µL. Prochilodus nigricans and Potamorhina altamazonica genomic DNA (gDNA) samples were extracted for use as a positive controls. The 12S and 16S genes from eDNA were amplified and sequenced with next generation Sequencing (NGS). Using a metabarcode approach, we used the 12S (12S-V5) and 16S (L2513/H2714) minibarcode universal primers to detect fish species DNA traces present in water samples from the Cacau lake. The NGS produced 18 and 492,454 12S and 16S minibarcode readings, respectively, for three taxonomic groups (Actinopterygii, Mammalia and Squamata). Adding the two genes, a total of 492,472.00 readings, with 15 readings with 12S and 4,431.082 readings with 16S for fish. Fish (Actinopterygii) represented 83.33% and 0.60% (three Orders, five families and five genus identified according to BLASTN), mammals had 11.11% and 99.40% and reptiles with 5.56% and 0.00% for the total readings of the 12S and 16S respectively, with more than 97% similarity to NCBI-available reference sequences. Taxonomic classification at the level of species was not very resolute when comparing OTU's with sequences published in NCBI.This study sets a milestone in the methodology of DNA extraction from floodplain lake, and shows the method can be used to monitor Amazon basin ichthyofauna, as it was possible to detect the presence of fish species DNA in collected water samples
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