Journal of fish biology最新文献

{"title":"Relationships between body length and bony structure measures in North American temperate freshwater fishes.","authors":"Kamden C Glade, Jay Holland, Baylor Short, Kendra Fink, Andrew W Hafs","doi":"10.1111/jfb.70042","DOIUrl":"https://doi.org/10.1111/jfb.70042","url":null,"abstract":"<p><p>Stomach content investigations of piscivorous fishes provide resource managers with valuable information concerning diet patterns, community structure and species interactions. Unique bony structures are often used to identify partially digested prey fish, and recent advancements in molecular techniques have provided increased taxonomic resolution of prey fish remains. However, gravimetric and volumetric methods only account for the partial remains recovered in the sample, which could lead to underestimates of the dietary contributions of digested prey items identified using these techniques. We therefore investigated relationships between total length and bony structures for multiple fish taxa observed in the diets of piscivorous fishes in Minnesota lakes using linear regressions. Cleithra, otoliths, backbone measurements, average vertebrae lengths and ictalurid pectoral spine lengths were used to create equations to estimate total length of digested prey. Predictive equations were developed for families, genera and species, as well as general equations averaged across all taxa. Nearly all equations were statistically significant (p < 0.001) and most had high predictive power (r² ≥ 0.85), although there was substantial variability among taxa and structures. These equations will give investigators an additional tool to maximize the information gained from fish diet studies.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144010866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abiotic environmental factors contribute to spatial variation in boldness and exploration in guppies (Poecilia reticulata).","authors":"Alexis M Heckley, Pierre-Olivier Montiglio, Janay A Fox, Sarah Sanderson, Alison M Derry, Kiyoko M Gotanda, Andrew P Hendry","doi":"10.1111/jfb.70058","DOIUrl":"https://doi.org/10.1111/jfb.70058","url":null,"abstract":"<p><p>Research on wild fishes has tended to overlook the role of abiotic factors in shaping behaviours associated with boldness and exploration. This oversight could exist because small-scale variation in the abiotic environment might seem unlikely to influence such behaviours. We challenged this assumption through research in the Trinidadian guppy (Poecilia reticulata) system. We started by quantifying how behaviours associated with boldness (time in a shelter and time frozen in an open field) and a behaviour associated with exploration (number of grid squares crossed in an open field) varied for guppies within and among 15 pools across two streams, where all of the pools within a stream were within 150 m of each other. The measured behaviours differed little between streams, yet they varied dramatically among pools within streams and among individuals within pools, thus illustrating how such behaviours can be structured on very small spatial scales. We next assessed how the observed behavioural variation might be explained by individual-level attributes (sex and body mass) and pool-level abiotic factors (e.g. temperature and dissolved oxygen). Individual-level attributes explained little of the behavioural variation, although smaller guppies did display slightly bolder behaviour. Among-pool abiotic factors, however, were quite informative. As a clear example, guppies from pools with less dissolved oxygen displayed bolder behaviour and (possibly) greater exploration. Our results highlight the importance of abiotic factors in shaping behaviour even on small spatial scales.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144019083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrative morphometric and molecular analyses reveal possible genetic contamination of silver catfish populations of the genus Rhamdia in Neotropical River basins.","authors":"Thaís Souto Bignotto, Herivelto Beck de Souza, Rafael Clovis da Silva Bronzim, Thiago Cintra Maniglia, Dirceu Baumgartner","doi":"10.1111/jfb.70057","DOIUrl":"https://doi.org/10.1111/jfb.70057","url":null,"abstract":"<p><p>Rhamdia quelen, Rhamdia branneri and Rhamdia voulezi are morphologically similar species that, until recently, were considered synonymous. Although R. quelen has wide distribution in the Neotropical region, R. branneri and R. voulezi are sympatric and endemic species of the Iguaçu River basin. We used an integrative approach, including morphometric and molecular data (barcodes DNA, COI gene), to assist in the identification and delimitation of these species. We also intended to investigate genetic contamination of the Paraná III and lower Iguaçu River basins, as silver catfish production has increased in southern Brazil, and accidental or occasional escapes to nature may pose risks to the genetic integrity of native populations. COI sequences and morphometric data were efficient in the characterization and differentiation of Rhamdia species and may be helpful tools in correctly identifying R. quelen, R. branneri and R. voulezi. Both morphometric and molecular analyses indicated the segregation of specimens into three groups. Although this separation coincided with the taxonomy and the collection site in the morphometric analyses, the taxonomic identification of most samples did not coincide with the molecular identification. This fact may be due to (i) incorrect morphological identification and/or (ii) escapes of pure species and/or interspecific hybrids from fish farms. The detection of COI haplotypes of R. quelen in the lower Iguaçu River, as well as COI haplotypes of R. branneri and R. voulezi in the Paraná III basin, combined with the morphometric and morphological characteristics of the specimens, reinforces the occurrence of hybrid specimens in these river basins. These results reveal the importance of characterizing species and interspecific hybrids of Rhamdia and the urgency to regulate aquaculture activities.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143999156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aquatic eDNA outperforms sedimentary eDNA for the detection of estuarine fish communities in subtropical coastal vegetated ecosystems.","authors":"Emma Isabelle Rossouw, Sophie von der Heyden, Nasreen Peer","doi":"10.1111/jfb.70056","DOIUrl":"https://doi.org/10.1111/jfb.70056","url":null,"abstract":"<p><p>In South Africa, mangrove forests and seagrass meadows often co-occur in estuarine systems and in combination host rich, often endemic biodiversity. There is an urgent need to explore community diversity in coastal vegetated ecosystems, given the degrading effects of climate change and anthropogenic pressures. Environmental DNA metabarcoding is a promising biomonitoring tool in South African coastal ecosystems, although studies highlight the need to optimise and standardise sampling protocols. This study aimed to contribute to developing sampling protocols by understanding the applicability of environmental DNA (eDNA) metabarcoding within coastal vegetated habitats and by investigating diversity using two different sample types. Aquatic and sedimentary environmental DNA samples from three estuaries along the east coast of South Africa, in combination with MiFish metabarcoding, detected 148 operational taxonomic units (OTUs) representing 67 fish genera from 50 families, although only 16% were resolved to species. We observed that aquatic eDNA samples detected 97% of the total fish diversity, suggesting that this is an efficient tool to comprehensively detect ichthyofaunal diversity. We did not detect different fish communities between mangroves and seagrasses and our findings underscore the importance of taking hydrological connectivity into consideration for sampling design. Overall, our work reinforces key considerations for future eDNA metabarcoding studies focused on fish fauna in estuaries, and therefore contributes to optimising sampling protocols to support the biomonitoring of coastal biodiversity.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143968254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Freshwater fish condition responses to hydrological disturbance are species- and scale dependent.","authors":"Maxwell C Mallett, Jason D Thiem, Gavin L Butler, Luke Carpenter-Bundhoo, Mark J Kennard","doi":"10.1111/jfb.70033","DOIUrl":"https://doi.org/10.1111/jfb.70033","url":null,"abstract":"<p><p>Modification of river flows is a major cause of freshwater fish population declines in many parts of the world. Identifying the precise mechanisms of these declines represents a significant challenge, as a range of stressors can simultaneously impact various components of fish health, fitness and population dynamics. Here we investigate the role of river flows and other biophysical factors on spatio-temporal variation in freshwater fish body condition in Australia's highly modified Murray-Darling Basin using three widely distributed native (Murray cod Maccullochella peelii, golden perch Macquaria ambigua and bony herring Nematalosa erebi) and one introduced (common carp Cyprinus carpio) species. Our aim was to uncover drivers of spatio-temporal variation in fish condition at two spatial extents: at the basin scale, utilising a flow regime disturbance index, and at the river-valley scale, employing individual flow gauge data to assess responses in fish condition to multiple measures of antecedent (365 day) flow. Linear mixed effects modelling revealed that at the basin scale, M. peelii and M. ambigua were in better condition in rivers with lower flow regime disturbance, and temporal trends in the condition of N. erebi, C. carpio and M. peelii reflected boom and bust dynamics related to wet and dry climate periods. At the river-valley scale, mean antecedent daily flow magnitude was significantly positively related to the condition of M. peelii, M. ambigua and C. carpio, whereas the number of high-flow days was negatively related to condition of N. erebi. Our study demonstrates that a simple body condition index calculated from routinely collected length-weight data is sensitive to multiple measures of hydrological disturbance in river systems that experience substantial temporal and spatial variability. We emphasise that studies considering multiple spatial scales are important for understanding complex scale-dependent mechanisms influencing fish condition.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144022672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving eel pass efficiency: The role of crest shape and water flow in facilitating upstream juvenile eel migration.","authors":"Michael J Williamson, Bryony E Allen, Jack A Brand, Charlotte Pike, Chris Sergeant, Chris Grzesiok, Rosalind M Wright, Adam T Piper","doi":"10.1111/jfb.70017","DOIUrl":"https://doi.org/10.1111/jfb.70017","url":null,"abstract":"<p><p>River connectivity is crucial for the European eel (Anguilla anguilla) to complete its complex life cycle, which is vital for upstream recruitment to the declining population of this critically endangered catadromous fish. Eel passes, or ladders, are frequently installed on riverine structures, such as dams and weirs, to mitigate barrier effects and restore connectivity for upstream migrating eel. Efforts to optimise the effectiveness of passes have previously focused on the ascent section, quantifying the effects of climbing substrate, longitudinal slope, lateral slope and flow rate. However, conditions at the pass crest also impact the rapidity and success of upstream movements. Using controlled experiments and custom-built eel passes with contrasting crest shapes (curved vs. sloped) and flow directions (ascending vs. descending), we quantified the effect of crest conditions on the attempt success, passage efficiency and speed of ascending juvenile eel. Only three of the four treatments (sloped ascending, curved descending and curved ascending) demonstrated passage efficiencies significantly greater than 50%. Transit speed at the crest was significantly quicker (~3.5 min) in passes with a curved crest shape and ascending flow compared to the control. Our findings indicate that simple modifications to the shape of the pass crest and the configuration of flow delivery can help minimise delay and enhance passage efficiency. This, in turn, will increase upstream migration success and contribute to conservation and management goals, such as the EU Eel Regulation and The Eels (England and Wales) Regulations 2009.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144063970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Contrasting thermal and hypoxic responses of species from blackwater and whitewater rivers.","authors":"Susana Braz-Mota, Rafael M Duarte, Adalberto L Val","doi":"10.1111/jfb.70059","DOIUrl":"https://doi.org/10.1111/jfb.70059","url":null,"abstract":"<p><p>In the Amazon basin, climate change is increasing water temperatures and CO₂ concentrations, which intensify environmental stressors for fish by increasing natural thermal regimes, reducing dissolved oxygen and pH levels. Extreme droughts, such as those recorded in 2023 and the new record set in 2024, have exacerbated these conditions and have led to widespread fish mortality. Amazonian rivers, which are characterized by contrasting whitewater and blackwater systems, provide unique habitats with distinct pHs and temperatures that shape biodiversity and species adaptations. With regional water temperatures projected to increase by 2.2-7.0°C by the end of the century, understanding the expected thermal vulnerability of Amazonian fish has become crucial. This study aims to investigate the influence of water type (blackwater vs. whitewater) on both thermal and hypoxia tolerances and hypoxia responses in different fish species following the extreme drought in 2023 and analyse these responses on individual and taxonomic levels. The results revealed significant variability in both thermal and hypoxia tolerances among species, with fish displaying a lower thermal safety margin in blackwaters. The contrasting thermal and hypoxia tolerances observed between blackwater and whitewater fishes highlight the complexity of their adaptive strategies in response to environmental stressors and are fundamental for predicting future conditions of the Amazonian environment under the current climate change scenario.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144019271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biochemical characterization and modulation by abscisic acid of aminopeptidase-N activity in the digestive tract of Dentudo Oligosarcus jenynsii from Mar Chiquita coastal lagoon (Buenos Aires, Argentina).","authors":"Ivan Ascazuri, Juan Cruz Toraño, Camila Albanesi, Alejandra López Mañanes, Maria Soledad Michiels","doi":"10.1111/jfb.70061","DOIUrl":"https://doi.org/10.1111/jfb.70061","url":null,"abstract":"<p><p>The determination of the existence and level of activity of specific digestive enzymes is commonly used as a tool to understand the functioning of the digestive machinery. The aim of this study was to determine the existence and biochemical characteristics of aminopeptidase-N (APN) activity in the digestive tract of Oligosarcus jenynsii from Mar Chiquita coastal lagoon (Buenos Aires) and its possible modulation by abscisic acid (ABA). Individuals were collected in November 2022 from freshwater tributaries of the coastal lagoon using a beach seine net. Juveniles and adults were immediately placed on ice after capture, whereas additional groups of juveniles were transported to the laboratory for in vitro experiments. Juveniles and adults exhibited APN activity in the intestine and liver, which was active across a wide range of pH and temperature, and followed Michaelis-Menten kinetics. Bestatin inhibited the activity in the intestine in both stages, but it had no effect on the liver. Adults exhibited higher specific APN activity in the intestine compared to juveniles. The presence of ABA in vitro decreased APN activity in both intestine and liver from juveniles. These results suggest the presence of APN in both juveniles and adults, as well as its differential modulation by ABA in juveniles.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144009827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insight into the biology, ecology and population trends of the brown skate, Raja miraletus Linnaeus, 1758, in the Balearic Islands.","authors":"Francesca Ferragut-Perello, Maria Valls, Sergio Ramírez-Amaro, Miquel Àngel Cortes-Pujol, Beatriz Guijarro, Francesc Ordines","doi":"10.1111/jfb.70051","DOIUrl":"https://doi.org/10.1111/jfb.70051","url":null,"abstract":"<p><p>We studied the life-history traits of the brown skate (Raja miraletus) population off the Balearic Islands, which is a species commonly caught as bycatch by the bottom trawl fishery in the Western Mediterranean. Samples and data were collected year-round from commercial catches and yearly during spring-summer from the International Bottom Trawl Survey in the Mediterranean. The maximum total length observed was 43 cm, consistent with other Mediterranean regions but smaller than in Tunisia and Egypt. Recruitment was higher in winter, aligning with the observed summer spawning peak. The smallest sexually active individuals were 34 and 32 cm for females and males, respectively; with L₅₀ values of 35.9 and 33.4 cm for females and males, respectively. Length-weight relationships differed between sexes for total weight but not for eviscerated weight, highlighting variations in the mass of the organs rather than the sexual dimorphism of carcasses. Growth parameters indicated slower growth (K = 0.14) and smaller L_∞ (49.63 cm) in the Balearic Islands compared to other Mediterranean areas. The estimated trophic level from stomach contents was 3.72 ± 0.63, with crustaceans appearing as its main prey (accounting for 96% of Index of Relative Importance), with an ontogenetic dietary shift observed between adults and juveniles, transitioning from a diet based on a greater proportion of small crustaceans to one that includes larger crustaceans and fish. Juvenile and adult populations are not bathymetrically segregated. Both mean annual density and frequency of occurrence showed stability over two decades, potentially linked to the decrease in fishing pressure on the shelf and the implementation of protected areas. However, the historical context of overexploitation in the area emphasizes the need to consider this stability cautiously. The results presented here enhance the understanding of R. miraletus in the Balearic Islands, providing critical data for potential management and conservation purposes.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144028265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new species of Characidium (Characiformes: Crenuchidae) from the Iguaçu National Park, Rio Iguaçu basin, Paraná, Brazil.","authors":"Bruno H M Stabile, Renan B Dos Reis, Alessandra V de Oliveira, Weferson J da Graça","doi":"10.1111/jfb.70035","DOIUrl":"https://doi.org/10.1111/jfb.70035","url":null,"abstract":"<p><p>A new species of Characidium is described from the Iguaçu National Park, Brazil. The new species can be diagnosed from the congeners by the absence of conspicuous vertical bars, blotches and spots along the sides of the body, the presence of a scaled isthmus and adipose fin, a series of scales below lateral line and the presence of a thin dark midlateral stripe. The reticulated colour pattern of melanophores along the posterior edge of scales found in the new species is similar to that found in C. xanthopterum, with which it presents 4.2% of genetic distance. Morphological and molecular analyses showed that it is a new species, supported by multiple species delimitation methods (Assemble Species by Automatic Partitioning, the General Mixed Yule Coalescent method, and the Poisson Tree Process and its Bayesian implementation). The new species is a sister group of C. itarare, a species that occurs in the Paranapanema river basin (upper Paraná river). Despite being located within a conservation unit, the new species is known from only two creeks, raising concerns about its long-term conservation.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}