Journal of Applied Ichthyology最新文献

{"title":"Revealing Natural Hybridization Between Hypophthalmichthys molitrix and Hypophthalmichthys nobilis Within Their Native Range (Xiangjiang River of China) Through Morphological and Molecular Approaches","authors":"Zhiliang Zuo,&nbsp;Qifan Wu,&nbsp;Zhitao Peng,&nbsp;Jin Xiang,&nbsp;Hewei Xiao,&nbsp;Cheng Li,&nbsp;Lu Tian,&nbsp;Feng Gao","doi":"10.1155/jai/4840616","DOIUrl":"https://doi.org/10.1155/jai/4840616","url":null,"abstract":"<p><i>Hypophthalmichthys molitrix</i> and <i>Hypophthalmichthys nobilis</i> are economically important freshwater fish species in China. During resource surveys in the Xiangluzhou section of Xiangjiang River, Changsha, in 2020, fish suspected to be natural hybrids of <i>H. molitrix</i> and <i>H. nobilis</i> were identified. To confirm this, we employed morphological and molecular analyses of <i>H. molitrix</i>, <i>H. nobilis</i>, and their suspected hybrids. Morphometric results revealed that most countable and measurable traits of suspected hybrids (<i>n</i> = 29) were intermediate between those of <i>H. molitrix</i> (<i>n</i> = 30) and <i>H. nobilis</i> (<i>n</i> = 26). However, the traits were slightly biased toward those of <i>H. molitrix</i>, representing an intermediate, transitional form indicative of hybridization. Genome resequencing followed by principal component analysis and population structure analysis indicated that the genetic composition of the suspected hybrids (<i>n</i> = 9) was intermediate between <i>H. molitrix</i> (<i>n</i> = 10) and <i>H. nobilis</i> (<i>n</i> = 9), containing nuclear genetic material from both species. These results confirmed the suspected hybrids as true hybrids of <i>H. molitrix</i> and <i>H. nobilis</i>. COI gene barcoding results showed that the suspected hybrids (<i>n</i> = 28) formed a single clade in the haplotype network and shared haplotypes exclusively with <i>H. molitrix</i> (<i>n</i> = 29), indicating that <i>H. molitrix</i> was the maternal parent. Furthermore, the asymmetric hybridization pattern suggested potential influence of physicochemical factors, such as water temperature, water quality, and flow velocity, which affect the affinity between sperm and egg cells. We propose that the natural hybridization of <i>H. molitrix</i> and <i>H. nobilis</i> originates from genetic exchange. The influence of Xiangjiang River’s unique aquatic ecological environment and hydraulic engineering projects, which have led to changes in flow regimes and the degradation of spawning grounds, have further altered the species’ ecological reproductive habits and disrupted reproductive isolation and natural hybridization. This study provides direct empirical evidence of natural hybridization between <i>H. molitrix</i> and <i>H. nobilis</i> within their native ranges in China through morphological and molecular research methods, thereby complementing previous hybridization inferences based on genomic data. These findings offer a novel view on fish hybridization theory.</p>","PeriodicalId":14894,"journal":{"name":"Journal of Applied Ichthyology","volume":"2025 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/jai/4840616","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145146751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aquaculture and Fisheries’ Potentials in the Ecologically Critical Areas (ECAs) of Sundarbans, Bangladesh: Recommendations to Policy Making","authors":"Khan Kamal Uddin Ahmed,&nbsp;Md Shariful Islam","doi":"10.1155/jai/9967329","DOIUrl":"https://doi.org/10.1155/jai/9967329","url":null,"abstract":"<p>This paper explores the aquaculture and fisheries’ potentials within the ecologically critical areas (ECAs) of the Sundarbans, Bangladesh, highlighting their socioeconomic importance and the urgent need for sustainable management practices. As the largest mangrove forest globally and a UNESCO World Heritage Site, the Sundarbans is a biodiversity hotspot and a vital source of livelihood for millions, rich in various aquatic species, including finfish and shellfish. However, the region faces significant challenges such as climate change, habitat degradation, and unsustainable fishing practices, which threaten its ecological balance and fisheries resources. Current fisheries’ management is hindered by inadequate conservation efforts and limited aquaculture practices, particularly in breeding and seed supply of economically important species. Unsustainable juvenile collection methods exacerbate the depletion of local fish stocks, posing further risks to biodiversity. The study underscores the need for comprehensive research initiatives aimed at enhancing breeding technologies, developing sustainable aquaculture practices, and promoting community engagement in resource management. Recommendations include establishing hatcheries for commercially important species to produce high-quality seed, thereby alleviating pressure on wild populations and strengthening the local economy. The paper advocates for the implementation of Integrated Coastal Zone Management (ICZM), community-based resource management, and enhanced legal frameworks to support sustainable aquaculture. By adopting a multistakeholder approach that balances environmental conservation, economic development, and social equity, the Sundarbans can realize its potential for sustainable fisheries and aquaculture, ultimately improving livelihoods and fostering ecological resilience. The paper calls for proactive, scientifically informed strategies to navigate the complexities of aquaculture, fisheries, and ecological health in this critical region.</p>","PeriodicalId":14894,"journal":{"name":"Journal of Applied Ichthyology","volume":"2025 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/jai/9967329","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145102331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Length–Weight Relationships, Condition Factors, and Form Factors of 10 Freshwater Small Indigenous Fish Species in a Wetland Ecosystem of Northwestern Bangladesh","authors":"Tariq-Al Kasif,&nbsp;Md. Mizanur Rahman,&nbsp;Imran Bin Younos,&nbsp;Md. Rajib Sharker,&nbsp;Mohammad Shadiqur Rahman,&nbsp;Md. Fakhrul Islam","doi":"10.1155/jai/5536545","DOIUrl":"https://doi.org/10.1155/jai/5536545","url":null,"abstract":"<p>A total of ten species of freshwater small indigenous fish species (SIFS) were examined in order to study their length–weight relations (LWRs), condition factors (<i>K</i>_<i>R</i>), and form factors (<i>a</i>_3.0) caught by a small-scale fishery from the Babu Mondoler beel<i>,</i> a wetland ecosystem in northwestern Bangladesh. In addition, the form factor (<i>a</i>_3.0) was calculated for ten freshwater fish species in worldwide habitats. The samples were collected between June 2021 and May 2022 with various fishing equipment and traps, including box traps, cast nets, and gill nets. The study focused on the following species: <i>Ailia coila</i> (Hamilton, 1822), <i>Amblypharyngodon mola</i> (Bleeker, 1854), <i>Channa punctata</i> (Bloch, 1793), <i>Channa straita</i> (Bloch, 1793), <i>Esomus danricus</i> (Hamilton, 1822), <i>Eutropiichthys vacha</i> (Hamilton, 1822), <i>Gagata cenia</i> (Hamilton, 1822), <i>Labeo catla</i> (Hamilton, 1822), <i>Lepidocephalichthys guntea</i> (Hamilton, 1822), <i>and Macrognathus aculeatus</i> (Bloch, 1786). Total length (TL) was strongly correlated with body weight (BW) (<i>p</i> &lt; 0.001). The slope <i>b</i> was between 2.55 and 3.38, with 7 species experiencing negative allometric growth, 1 species experiencing positive allometric growth, and 2 species experiencing isometric growth. The mean relative condition factor (<i>K</i>_<i>R</i>) ranged from 0.9746 ± 0.0870 (<i>Channa punctata</i>) to a maximum of 1.0344 ± 0.2101 (<i>Ailia coila</i>) as a benchmark of the well-being of individuals of the various species in the same ecosystem. In our studied ecosystem, we observed a form factor (<i>a</i>_3.0) ranging from 0.0025 to 0.0151. The results on LWRs, condition factors, and form factors are important baseline data for monitoring the status of fish populations, detecting environmental stress, and sustainable management. Therefore, habitat action is required to reduce the growth-affecting stressors on these SIFS.</p>","PeriodicalId":14894,"journal":{"name":"Journal of Applied Ichthyology","volume":"2025 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/jai/5536545","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145038240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Length-Weight Relationships of Sixteen Fish Species From the Upper Tietê Basin, Southeaster Brazil","authors":"Luís Gustavo Nogueira de Carvalho,&nbsp;Beatriz Carine Gazzola Prieto,&nbsp;Camila Silva Bento,&nbsp;Dalton Jorge Neief Ganem,&nbsp;Matheus Oliveira Fagaça,&nbsp;Ariane Almeida Vaz,&nbsp;Welber Senteio Smith","doi":"10.1155/jai/3200000","DOIUrl":"https://doi.org/10.1155/jai/3200000","url":null,"abstract":"<p>This study investigated the length-weight relationship (LWR) of 16 fish species from the Upper Tietê Basin under the influence of the Atlantic Forest biome, aiming to provide updated morphometric data and contribute to the knowledge of Neotropical ichthyofauna. 2811 specimens were collected and distributed across five orders and 10 families. Standard length ranged from 0.8 to 24.5 cm, and weight from 0.01 to 34.19 g. The parameters <i>a</i> and <i>b</i> of equation <i>W</i> = <i>a</i>·<i>L</i>^<i>b</i> were estimated, revealing that most species exhibited allometric growth, with one isometric species (<i>Astyanax lacustris</i>), seven with negative allometry, and eight with positive allometry. The <i>b</i> values ranged from 2.579 (<i>Imparfinis piperatus</i>) to 3.651 (<i>Phalloceros reisi</i>), the latter being the only one outside the typical range of 2.5 &lt; <i>b</i> &lt; 3.5. The Bayesian analysis proposed by Froese indicated morphological deviations for <i>Hyphessobrycon multifasciatus</i> (α outside the expected range) and a lack of specific classification for <i>Cambeva iheringi</i>, <i>Geophagus iporangensis</i>, and <i>Osteogaster aenea</i>. An apparent scarcity of geographically delimited studies in the basin was evident, hindering broader comparisons. Only <i>Phalloceros reisi</i> presented compatible data, with mean, standard-length values similar to those reported in the literature. Also noteworthy is <i>Pseudotocinclus tietensis</i>, a threatened species that exhibited positive allometry (<i>b</i> = 3.2595), suggesting favorable environmental conditions for its growth in the studied basin. The results highlight the importance of regional morphometric studies as tools for monitoring and conserving ichthyofauna, especially for species whose morphometric characteristics had not yet been documented for the Upper Tietê Basin.</p>","PeriodicalId":14894,"journal":{"name":"Journal of Applied Ichthyology","volume":"2025 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/jai/3200000","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145022054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Growth Patterns and Body Condition of Notothenioid Fish (Genus Trematomus) From the Antarctic Peninsula and Weddell Sea","authors":"Mario La Mesa,&nbsp;Federico Calì","doi":"10.1155/jai/1341030","DOIUrl":"https://doi.org/10.1155/jai/1341030","url":null,"abstract":"<p>Growth patterns and body condition of 10 species of <i>Trematomus</i> (family Nototheniidae) collected off the Antarctic Peninsula and in the Weddell Sea during seven cruises carried out between 2002 and 2022 were estimated by length–weight relationships (LWRs) and relative condition factors (<i>K</i>_rel). Most of the investigated species exhibited positive allometric growth, except for males of <i>T. scotti</i> and females of <i>T. tokarevi</i>, which showed isometric growth. Sex-related differences of slope (b) in the LWRs were recorded only in <i>T. eulepidotus</i> and <i>T. scotti</i>. No slope differences were found when comparing populations from the two sampling areas. The form factor, derived from the LWR parameters, was a reliable indicator of body shape and was consistent with the mode of life of each species. <i>K</i>_rel was evenly distributed around unity, although data dispersion differed among the species. The overall similarity of growth patterns and body condition among the different species of <i>Trematomus</i> was likely due to their genetic similarity and common life history strategies despite their wide spatial distributions and different modes of life.</p>","PeriodicalId":14894,"journal":{"name":"Journal of Applied Ichthyology","volume":"2025 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/jai/1341030","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144990663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Storage Time and Temperature on Subsequent Wet Weight and Percent Dry Weight of Fundulus heteroclitus","authors":"Ethan M. Hobbs,&nbsp;Timothy F. Sheehan,&nbsp;Kenneth Oliveira,&nbsp;Mark J. Wuenschel","doi":"10.1155/jai/5091866","DOIUrl":"https://doi.org/10.1155/jai/5091866","url":null,"abstract":"<p>Fisheries monitoring and research often requires preservation of fish samples for later analysis in the laboratory. Freezing is a common method, but it can affect subsequent fish size and composition, and the interpretation of metrics based on them. We evaluated the effects of freezing on fish wet weight, dry weight, and the percentage dry weight (a measure often used to estimate energy density). Specifically, we quantified changes in the weight of individual mummichogs (<i>Fundulus heteroclitus</i>) frozen at different temperatures (−20°C and −80°C) for 1–3 months. In addition, a temperature change treatment where fish were initially frozen at −80°C for one month before transfer to −20°C for an additional 1–3 months was included to simulate protocols typically used at sea. Individual wet weights were measured before freezing, and after freezing, the wet weights, dry weights, and percentage dry weights were determined. All freezing treatments resulted in minor but significant (<i>p</i> &lt; 0.05) water loss. While the change was measurable and directional, it did not have a significant effect on the percentage dry weight except for samples held at −20°C for 3 months. A similar increase in percent dry weight was not evident in the temperature change group that was also stored at −20°C for 3 months. The least amount of weight loss, and therefore bias, was in the −80°C group, followed by the temperature change group, with the −20°C treatments losing the most water. The results indicate that if specimens for percent dry weight estimation have to be frozen, −20°C is okay for a short period of time (1–2 months), but when longer storage times are needed, −80°C is the best, even if only for the initial freezing period.</p>","PeriodicalId":14894,"journal":{"name":"Journal of Applied Ichthyology","volume":"2025 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/jai/5091866","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144929525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Length–Weight Relationship in Food Fish Species From the Upper Putumayo River Basin, Colombia","authors":"César A. Bonilla-Castillo,&nbsp;Edwin Agudelo Córdoba","doi":"10.1155/jai/3116845","DOIUrl":"https://doi.org/10.1155/jai/3116845","url":null,"abstract":"<p>The length–weight relationship (LWR) in fish is an important tool because it allows understanding aspects such as growth assessment, body condition, and biomass estimation. The aim of this study was to determine the LWR of food fish species from the Amazonian plain of the Putumayo River caught by artisanal fisheries to be sold in the town of Puerto Leguízamo between 2018 and 2023. More than 19,000 individuals of 31 species were registered. Each fish was taxonomically identified at the species level, recording its standard length (cm) and weight (g). Searches in FishBase revealed that six species lack referenced data, twenty five are not reported for the Putumayo Basin, and five are in the vulnerable category, according to the International Union for Conservation of Nature (IUCN). The relationship data calculated in this study are the first publications for these species in this region of the Amazon Basin. Knowledge of these biometric data and their relationships is relevant for managing and conserving fish and fisheries.</p>","PeriodicalId":14894,"journal":{"name":"Journal of Applied Ichthyology","volume":"2025 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/jai/3116845","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144927470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reproductive Biology and Feeding Habits of Sillago sihama (Forsskal, 1775) and Sillago mengjialensis (Gao, Baki, and Saha, 2022) in Bay of Bengal, Bangladesh","authors":"Prianka Kundu,&nbsp;Md. Azharul Islam Palash,&nbsp;Anirban Sarker,&nbsp;Subrina Sehrin,&nbsp;Tianxiang Gao,&nbsp;Mohammad Abdul Baki,&nbsp;Shilpi Saha","doi":"10.1155/jai/5384400","DOIUrl":"https://doi.org/10.1155/jai/5384400","url":null,"abstract":"<p>This study investigates the reproductive biology, feeding habits, and growth pattern of <i>Sillago sihama</i> (<i>N</i> = 119) and <i>Sillago mengjialensis</i> (<i>N</i> = 18) collected from Cox’s Bazar, Bay of Bengal, between August 2022 and October 2023. The total length and body weight of <i>S. sihama</i> ranged from 72.19 to 173.50 mm and from 2.49 to 41.32 g, respectively, while they ranged from 78.32 to 159.81 mm and from 3.08 to 27.19 g, in <i>S. mengjialensis</i>, respectively. The sex ratio was male-dominated in both species. Peak gonadosomatic index (GSI) values were recorded in March for <i>S. sihama</i> (females: 0.653 ± 0.121; males: 0.351 ± 0.022) and in November for <i>S. mengjialensis</i> (females: 3.600 ± 0.371; males: 1.068 ± 0.115), indicating distinct and separate spawning seasons. In both species, males matured at smaller size, compared to females, with Lm₅₀ estimated at 93.73 and 98.76 mm for male and female <i>S. sihama</i>, and 86.00 and 128.14 mm for male and female <i>S. mengjialensis</i>, respectively. Histological examination identified immature and mature males and immature and maturing females in <i>S. sihama</i>, whereas mature males and fully ripe females were observed in <i>S. mengjialensis</i>. Fecundity in <i>S. mengjialensis</i> ranged from 8548 to 16,716 eggs per ovary. Feeding analysis revealed omnivory in <i>S. sihama</i> (RLG: 1.12) and carnivory in <i>S. mengjialensis</i> (RLG: 0.75). Length–weight relationships indicated positive allometric growth (<i>b</i> = 3.453) in <i>S. sihama</i> and isometric growth (<i>b</i> = 3.08) in <i>S. mengjialensis</i>. These findings provide important baseline data for future management, conservation, and stock assessment of these species.</p>","PeriodicalId":14894,"journal":{"name":"Journal of Applied Ichthyology","volume":"2025 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/jai/5384400","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144923460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Delineating African Catfish (Clarias gariepinus Burchell, 1822) Populations Through Molecular Genetic Approaches to Contribute to Aquaculture Performance in Uganda","authors":"Papius Dias Tibihika,&nbsp;Cassius Aruho,&nbsp;Victoria Namulawa,&nbsp;Richard Ddungu,&nbsp;Gertrude Atukunda,&nbsp;Margaret Aanyu,&nbsp;Mujibu Nkambo,&nbsp;Gerald Kwikiriza,&nbsp;Thapasya Vijayan,&nbsp;Manuel Curto,&nbsp;Harald Meimberg","doi":"10.1155/jai/5645753","DOIUrl":"https://doi.org/10.1155/jai/5645753","url":null,"abstract":"<p>Aquaculture in Uganda is mainly anchored on two fish species: Nile tilapia (<i>Oreochromis niloticus</i>) and the Ugandan African catfish (<i>Clarias gariepinus</i>). The Ugandan <i>C. gariepinus</i> is popular among farmers nationwide because of its desirable traits, such as high growth rates, a broad array of trophic levels, and resistance to diseases and parasites. Nevertheless, the species’ productivity is limited by insufficient molecular genetic data that can be used to inform selective breeding efforts. We fill this gap by sequencing the mtDNA D-loop of 192 <i>C. gariepinus</i> individuals from five major water bodies of Uganda. The results show that the Western Rift Valley lakes (Edward, George, and Albert) are more genetically diverse, with the least being the Central region lakes, particularly the Kyoga basin lakes. <i>Fst</i> values and the haplotype network group the <i>C. gariepinus</i> populations into two genetic clusters: the Western Rift Valley lakes (Albert, Edward, and George systems) and the Lakes Victoria and Kyoga systems. In particular, the current study reveals that Lakes Edward and George are likely a panmictic population. However, we noted genetic heterogeneity in L. Victoria, relatively indicating within-lake genetic structure. These results present the initial steps for genetically characterizing the Ugandan <i>C. gariepinus</i> populations and are key to guiding the use of the wild stocks in aquaculture for selective breeding programs to propel fish farming in Uganda.</p>","PeriodicalId":14894,"journal":{"name":"Journal of Applied Ichthyology","volume":"2025 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/jai/5645753","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144918735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Age Structure, Growth, and Sex Ratio of Coilia nasus in the Lower Yangtze River and the Estuary During the Initial Stage of Fishing Moratorium","authors":"Hongyi Guo,&nbsp;Xuguang Zhang,&nbsp;Ya Zhang,&nbsp;Kai Liu","doi":"10.1155/jai/6288170","DOIUrl":"https://doi.org/10.1155/jai/6288170","url":null,"abstract":"<p>The comprehensive 10-year fishing moratorium implemented in the Yangtze River Basin since 2021 provides a unique opportunity to evaluate the recovery of threatened fish populations. This study assessed the recovery status of <i>Coilia nasus</i> in the lower reaches of the Yangtze River during the fourth year of the moratorium through analysis of age structure, growth parameters, and sex ratio. Field investigations were conducted at two strategic locations (Chongming and Taizhou) during the migration season (May–June 2024), yielding 3077 specimens. Results revealed significant improvements in population parameters, including increased mean age (2.64 years) and standard length (28.5 cm), alongside a higher proportion of age 3 and age 4 individuals (63.3%). Sex ratio analysis showed a pronounced female bias (3.19:1), with spatial variations between estuarine (4.99:1) and upstream (2.04:1) sites. Growth parameter analysis indicated a shift toward natural growth dynamics, with increased asymptotic length (<i>L</i>_<i>∞</i>) and altered growth rates (<i>k</i>) compared to premoratorium periods. Despite these positive indicators, the absence of five-year-old individuals and lower average length compared to historical records suggest incomplete recovery. Our findings provide evidence for the effectiveness of the fishing ban while highlighting the need for continued protection.</p>","PeriodicalId":14894,"journal":{"name":"Journal of Applied Ichthyology","volume":"2025 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/jai/6288170","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144881359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}