European Journal of Aquatic Sciences最新文献

{"title":"Assessment of Metal Concentration and Bioaccumulation Factor in Surface Water and Fishes Sampled From Four Creeks in the Bonny River Estuary, Niger Delta Region of Nigeria","authors":"Fredrick Igila Allison, O. Ihunwo, Ibiene Allison","doi":"10.24018/ejaqua.2024.3.1.18","DOIUrl":"https://doi.org/10.24018/ejaqua.2024.3.1.18","url":null,"abstract":"\u0000\u0000\u0000\u0000The indiscriminate disposal of industrial and urban waste has added to the concerns of global water pollution. Anthropogenic activities and activities of oil companies (oil spills) have also contributed to the pollution of the aquatic ecosystem in the Niger Delta region of Nigeria. This study was therefore designed to evaluate the concentration of Iron, Nickel, Lead, Cadmium and Chromium in our surface waters and our marine life. Samples of surface water were collected into 50 cl sterile plastic bottles and labelled accordingly. Twenty medium-sized tilapia fishes from about a one-kilometre radius of each site were caught and also labelled accordingly. Water and fishes from each site were then kept in a cooler, iced and immediately transported to the laboratories for analysis for heavy metals after these fishes were homogenised using a blender. Atomic absorption spectrophotometer was used for the metal analysis. Standards were prepared using tracecert of each of the above-mentioned metals. The results of these study sites (Akpajo, Okujagu, Woji and Elelenwo) had high concentrations of metals. Fishes from all these sites also had high concentration of these metals. The trend of metal concentration in the surface water as follows: Okujagu–Pb>Cr> Cd>Fe = Ni, Akpajo–Cd>Fe>Pb>Cr>Ni, Elelenwo–Pb>Cr>Fe>Cd>Ni, Woji–Cr>Cd>Pb>Fe>Ni. Results obtained also revealed the trend of metal concentration in fish muscles as follows: Okujagu–Pb>Cr> Cd>Fe = Ni, Akpajo– Cd>Fe>Pb>Cr>Ni, Elelenwo–Pb>Cr>Fe>Cd>Ni and Woji–Cr>Cd>Pb>Fe>Ni. Fishes and surface water sampled from these four creeks in the Bonny estuary in the Niger Delta region of Nigeria had high concentrations of iron, nickel, cadmium, chromium and lead in relation to their concentration in surface water. The results of this study revealed that metal concentration in surface water had some relative effect on their concentration in the fishes. This, therefore, means consumption of these fishes may lead to the accumulation of these metals in man to a toxic concentration. This may be one of the reasons for the increase in some heavy metal-related health issues (diabetes, renal diseases) in this region.\u0000\u0000\u0000\u0000","PeriodicalId":427434,"journal":{"name":"European Journal of Aquatic Sciences","volume":"56 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140255086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"What Are the Prospects of Sustainable Aquaculture in the Niger Delta, Nigeria?","authors":"Lilian O. Elekwachi","doi":"10.24018/ejaqua.2023.2.2.12","DOIUrl":"https://doi.org/10.24018/ejaqua.2023.2.2.12","url":null,"abstract":"Globally, the wild capture fishery is declining, and aquaculture is expanding to help fill the gap, especially in Asia and developing countries. However, the sustainability of the aquaculture sector is raising questions, and answering those questions requires the adoption of new technologies and better management practices. Nowhere is this seen more clearly than in Nigeria where aquaculture generally means catfish, the most farmed species of which is clarias garipinus because it is a native species, and it plays an important role in the average Nigerian diet. However, small-scale catfish aquaculture businesses are affected by various challenges that threaten the sustainability of the sector. Prominent among these challenges are: poor management skills; lack of good quality fish seed supply; high cost of fish feed; inconsistency in government policy and limited regulations; lack of consideration about the impacts of aquaculture practice on the environment causing water pollution and environmental degradation, and insecurity of investment against natural disasters such as floods. This research investigated these challenges in eight sites in two states (Delta and Bayelsa) in the Niger Delta region of Nigeria. Data were gathered from a survey questionnaire, key informant interviews, personal observations, and published literature. Key findings showed that the sustainable development of the small-scale catfish farming industry in Delta and Bayelsa states is vulnerable to several threats that prevent it from fulfilling its undoubted potential to grow into a much larger sector, which could significantly reduce Nigeria’s reliance on fish imports, as well as relieve pressure on the overfished marine catch sector. Nevertheless, despite the threats, most catfish farmers are committed to their work and deserve the support of the government to enable them to succeed.","PeriodicalId":427434,"journal":{"name":"European Journal of Aquatic Sciences","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136307923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolation and Characterization of the Immunoglobulin (IgM) from Oreochromis niloticus in Brazil","authors":"D. C. Dias, L. Tachibana, E. E. Bach","doi":"10.24018/ejaqua.2023.2.1.11","DOIUrl":"https://doi.org/10.24018/ejaqua.2023.2.1.11","url":null,"abstract":"The objective of study was to isolate immunoglobulin (IgM) from the serum of tilapia found in Brazil, characterize its molecular mass, and evaluate it by serological tests. Results showed that IgM had a tetrameric structure with 81 kDa heavy chain and 40 kDa light chain, probably being another lineage of those described in scientific articles in other countries. Immuno-electrophoresis confirmed the IgM and, in the double diffusion agar test, the homologous reaction was observed. Elisa test was developed to quantify the IgM produced by tilapia. These techniques could be used in future tilapia projects involving vaccine production.","PeriodicalId":427434,"journal":{"name":"European Journal of Aquatic Sciences","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116536144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal Variation of the Ecological Water Quality in a Drinking Water Supply Dam Lake in Bongouanou (Côte d’Ivoire)","authors":"Nathalie Akissi Kouadio, Danielle Rose Benié Aboua, S. S. Yao","doi":"10.24018/ejaqua.2023.2.1.8","DOIUrl":"https://doi.org/10.24018/ejaqua.2023.2.1.8","url":null,"abstract":"The Ichthyological Index of Wetlands (IIW), for the monitoring of the water quality of Ehuikro Lake in Bongouanou, was established. Monthly, experimental gillnet fisheries were conducted between July 2017 and June 2018 in Lake Ehuikro (Bongouanou, Ivory Coast). The fish collected were identified and counted each month, as well as the physicochemical parameters measured in-situ. A partial canonical correspondence analysis (pCCA) was used to order fish species along the axes according to physicochemical parameters to explain anthropogenic disturbances. It appears from this analysis that the water of Lake Ehuikro is of \"good quality\" during the rainy season and of \"poor quality\" during the dry season.","PeriodicalId":427434,"journal":{"name":"European Journal of Aquatic Sciences","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134120319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Status of Ichthyofauna under Conservations and Threats in the Historical Pahang River, Pahang, Malaysia","authors":"Md. Asek Uddin, Mt. Nur-A-Sharmin Aktar","doi":"10.24018/ejaqua.2022.1.1.6","DOIUrl":"https://doi.org/10.24018/ejaqua.2022.1.1.6","url":null,"abstract":"The aim of the present review is based on fish diversity status in the historical Pahang River, Pahang, Malaysia to represent the status of fish composition and its investigation with IUCN status for future monitoring and conservation purposes to the critical fish species. Secondary data were collected from published articles, reviews, field visits, GIS mapping, and books. A total of 259 fish species belonging 19 orders, 50 families, and 146 genera were recorded from the Pahang River waters. Fish from the order Cypriniformes belongings to the family Cyprinidae was documented the most dominant fish group as highest number of species (87 species) followed by the family Siluridae (18 species), Bagridae (16 species), Cobitidae (16 species), Osphronemidae (12 species) and Balitoridae (10 species). Available fishery resources need to be managed carefully as 9 commercial fish species (28.8%) are currently vulnerable and may be extinct in near future. Furthermore, the presence of 14 introduced fish species in the Pahang River waters also requires attention from the respective authorities due to the potential disruption to balance of aquatic systems and ecological circles. Changing land use issues in the Pahang River such as siltation, watershed destruction, rainforest degradation, conversion of wetlands to agricultural and industrial development, land reclamation, mining and logging, construction of barrages and flood mitigation channels. In addition, unstable climatic pattern such as seasonal vast flooding and irregular disturbance by human, illegal and destructive fishing, environmental imbalanced through poisons and pollutants would be significant challenges to the fish diversity management in the historical Pahang River. This study implies to biomonitoring in the Pahang River to ensure sustainable management to aquatic fauna for further studies and development. Thus, effective and necessary mitigation steps should be proposed to protect our valuable bioresources from the Pahang River.","PeriodicalId":427434,"journal":{"name":"European Journal of Aquatic Sciences","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127905440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Control Copepod Abundances and Kilka Catch by Invasive Predator Mnemiopsis leidyi A. Agassiz, 1868 in the Southern Caspian Sea","authors":"Aboulghasem Roohi","doi":"10.24018/ejaqua.2022.1.1.1","DOIUrl":"https://doi.org/10.24018/ejaqua.2022.1.1.1","url":null,"abstract":"The Caspian Sea has a variety of species and groups of aquatic animals, e.g., plankton and fishes that are exploited, unfortunately in the past decade, this sea has entered and expelled of some non-indigenous species such as ctenophore Mnemiopsis leidyi, Copepods Acartia tonsa, Balanidae Balanus improvisus and Mullets Lisa saliens have caused major changes in the Sea. One of the species got common in the coastal waters is M. leidyi with the highest biomass in summer at the temperature of 25-30 °C, and the highest abundance was observed in autumn while the minimum density was in winter of 8-10 °C. The ctenophore distribution of length frequency indicated that while 83% of the population consists of larval and immature organisms, only less than 17% belonged to the adult group in the costal waters of the Caspian. The largest size of the jelly was 70 mm long in the southern Caspian Sea in September 2002. Based on the jelly food consumption, the Nauplius, copepodites and adults of Acartia tonsa consisted 66% and bivalves was 13% in the Caspian. Therefore, it seems the reduction of the comb jelly compared to its early year's invasion was due to the reduction of edible zooplankton especially A. tonsa in the southern of the Caspian Sea. During 2001-2013, Kilka catches amount was decreased to ~15000 kg from 95000 kg in 1996 with the changes of Clupeidae species composition of Clupeonella engrauliformis to C. cultriventris caspia.","PeriodicalId":427434,"journal":{"name":"European Journal of Aquatic Sciences","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122180665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Addressing Amazonian Fish Diversity Using Environmental DNA (eDNA): A First Glance","authors":"Larissa Matos Batista, Carolina Sousa De Sá-Leitão, Érica Martinha Silva de Souza, Carlos Henrique Dos Anjos-Santos, V. M. D. de Almeida-Val","doi":"10.24018/ejaqua.2022.1.1.4","DOIUrl":"https://doi.org/10.24018/ejaqua.2022.1.1.4","url":null,"abstract":"Environmental DNA (eDNA) is considered to be an innovative method that can be used in the detection and identification of species present in aquatic environments, adding the advantage of describing the ichthyofauna without capturing the organisms. Out of the two possible approaches of eDNA, the metabarcoding approach aims to identify the diversity of a specific taxon and its composition using a universal DNA primer. This approach has grown considerably in recent years, although most studies focus on temperate regions, which causes a lack of clarity about the potential of the method in tropical regions since these have very distinct abiotic characteristics, as well as a higher diversity of fauna and flora. Therefore, as a way to verify the potential use of eDNA metabarcoding, this study focused on the Neotropical region, specifically the Amazon basin, a place with the highest ichthyofaunistic biodiversity in the world. As such, the goal of this study was to detect the composition of the main taxonomic groups of fish in the small stream Tarumã-Mirim, an acidic blackwater river that is located nearby Manaus city and is part of an environmental protection area near the city of Manaus, Brazil. For that, water samples of 6 L were collected along the river at 5 points (totaling 30 L). The water samples were stored in ice boxes and transported to the laboratory for filtration in fiberglass filters. Following the filtration and the extraction of eDNA, the samples were amplified in PCRs machines, using the universal primers MiFish developed by Miya et al., (2015). The next steps were: the construction of eDNA libraries, the sequencing on Illumina – Miseq platform, and a bioinformatic analysis. For the taxonomic identification of the eDNA sequences we used the sequences deposited in GenBank and the reference database developed specifically for Amazonian fish. The application and efficiency of eDNA metabarcoding for the samples, identified 42 molecular operational taxonomic units (MOTUs), which were grouped into six orders and eight families. A refined approach identified seven species and one genus. In addition, since eDNA samples were obtained along the entire river, it was possible to build a distribution map of fish species. Despite the limitation in identifying the abundance of all taxonomic groups present in the Tarumã-Mirim River, the metabarcoding approach for the eDNA was able to identify the species that have their contemporary distribution in the Amazonian rivers, as well as the detection of the three main groups of fish. Thus, the method may serve as a complement to ecological studies for the detection, identification and monitoring the Amazonian ichthyofauna. These results show that the eDNA approach needs to be optimized in tropical regions since the biotic and abiotic characteristics, which are peculiar to the tropics (acidic waters, high temperatures, etc.), may affect the adequate detection of the rich biodiversity of such sites","PeriodicalId":427434,"journal":{"name":"European Journal of Aquatic Sciences","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130517779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Phylogenetic Analysis of Caridina weberi Species Group around Japan, with the First Record of Caridina tupaia de Mazancourt, Marquet & Keith, 2019 (Crustacea: Decapoda: Atyidae) from Japan","authors":"Hiroto Nagai, Tadashi Kitano, H. Imai","doi":"10.24018/ejaqua.2022.1.1.3","DOIUrl":"https://doi.org/10.24018/ejaqua.2022.1.1.3","url":null,"abstract":"Recently, numerous new species of Caridina weberi species group were described from around Polynesia. This study reports the molecular phylogenetic data of the Japanese specimens belonging to C. weberi species group based on the mitochondrial 16S rRNA and cytochrome c oxidase subunit I gene. The results suggested that C. laoagensis Blanco, 1939, C. macrodentata Cai & Shokita, 2006, C. multidentata Stimpson, 1860, C. prashadi Tiwari & Pillai, 1971 and C. tupaia de Mazancourt, Marquet & Keith, 2019 are distributed in Japan. This is the first record of C. tupaia on Ishigaki-jima Island, Ryukyu Archipelago, southern Japan and the northernmost record of this shrimp. Attempted to find C. okinawa, belonging to C. weberi species group, for the first time in about 50 years, but there were no Atyid shrimps in its type locality. Based on the data of mitochondrial DNA fragments, we suggest that if the divergence estimate in C. weberi species group exceed 3% for 16S rRNA, it may be an interspecific variation. We also reveal the existence of two unnamed species which had been identified as C. macrodentata and C. multidentata. Caridina multidentata is known to be distributed in Japan (type locality), Taiwan, Fiji and Madagascar, however East Asian and  Malagasy samples were shown to be distinct species, their divergence estimates were more than 10% for 16S rRNA. We also provide the key to the Japanese species of C. weberi species group.","PeriodicalId":427434,"journal":{"name":"European Journal of Aquatic Sciences","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130015637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}