The devil firefish, Pterois miles, an invasive alien species, presents a growing threat to marine biodiversity due to its rapid population expansion and significant ecological impacts in the Eastern Mediterranean Sea. This study, conducted between February 2020 and April 2021, aimed to assess the growth patterns and reproductive behaviour to better understand its invasion dynamics in Turkey. Monthly sampling revealed its length-weight relationship, with positive allometric growth. The reproductive dynamics showed a prolonged spawning season from June to November, with females displaying high fecundity, averaging 20,743 oocytes per batch. Females reached first maturity at 20.1 cm total length, and its natural mortality rate was estimated at 0.8 per year. Understanding life-history characteristics of lionfish is important for understanding its invasion success and may help develop effective measures to control its invasion to protect regional marine native biodiversity.
{"title":"Growth and reproductive dynamics of the devil firefish, Pterois miles (Bennett, 1828), in the Eastern Mediterranean Sea.","authors":"Taner Yıldız, Nazli Demirel, Aylin Ulman, Özgür Çanak, Mert Kesiktaş, Hilal Buyuran, Utkuhan Şahinoğlu, Nurdan Cömert, Lütfiye Eryılmaz, Emre Yemişken","doi":"10.1111/jfb.70296","DOIUrl":"https://doi.org/10.1111/jfb.70296","url":null,"abstract":"<p><p>The devil firefish, Pterois miles, an invasive alien species, presents a growing threat to marine biodiversity due to its rapid population expansion and significant ecological impacts in the Eastern Mediterranean Sea. This study, conducted between February 2020 and April 2021, aimed to assess the growth patterns and reproductive behaviour to better understand its invasion dynamics in Turkey. Monthly sampling revealed its length-weight relationship, with positive allometric growth. The reproductive dynamics showed a prolonged spawning season from June to November, with females displaying high fecundity, averaging 20,743 oocytes per batch. Females reached first maturity at 20.1 cm total length, and its natural mortality rate was estimated at 0.8 per year. Understanding life-history characteristics of lionfish is important for understanding its invasion success and may help develop effective measures to control its invasion to protect regional marine native biodiversity.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145661416","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}
The European catfish (Silurus glanis) is a giant Eurasian freshwater fish that has become a high-impact invasive species in Western Europe. In Spain, it was first introduced in 1974 in the Ebro River for sport fishing, and has since spread to multiple river basins, despite bans. We compiled all known occurrence records in Spain (1974-2024) from scientific surveys, government databases and citizen science, standardizing them on a 10 × 10 km grid. Using first-detection data per waterbody, we reconstructed the invasion timeline and calculated decadal expansion rates. We then applied nonlinear models to project future spread up to 2030. S. glanis now occupies seven major Iberian basins, expanding from one grid cell in the 1970s to 129 cells by 2024. The invasion was initially slow (1970s-1990s), followed by a rapid expansion from 2000 to 2009, when the area occupied increased six-fold. Since 2010 its expansion has moderated, although new introductions in the Duero, Guadalquivir and Andalusian Mediterranean basins have driven localized explosive growth. Logistic and Gompertz models suggest the invasion may be approaching saturation in long-invaded basins (e.g. Ebro), projecting only a slight increase in total area occupied by 2030. However, model confidence intervals remain broad, reflecting uncertainty due to potential illegal translocations and climate-driven habitat changes in the future. Our findings underscore the urgent need for proactive management: preventing human-mediated jump dispersal, enhancing monitoring for early detection and enforcing regulations. Continued data updates and risk modelling are vital to inform policy and targeted control against this high-risk invader.
{"title":"Past trends and future scenarios in the distribution of European catfish Silurus glanis in Spain.","authors":"Carlos Fernández-Delgado, Mercedes Herrera","doi":"10.1111/jfb.70303","DOIUrl":"https://doi.org/10.1111/jfb.70303","url":null,"abstract":"<p><p>The European catfish (Silurus glanis) is a giant Eurasian freshwater fish that has become a high-impact invasive species in Western Europe. In Spain, it was first introduced in 1974 in the Ebro River for sport fishing, and has since spread to multiple river basins, despite bans. We compiled all known occurrence records in Spain (1974-2024) from scientific surveys, government databases and citizen science, standardizing them on a 10 × 10 km grid. Using first-detection data per waterbody, we reconstructed the invasion timeline and calculated decadal expansion rates. We then applied nonlinear models to project future spread up to 2030. S. glanis now occupies seven major Iberian basins, expanding from one grid cell in the 1970s to 129 cells by 2024. The invasion was initially slow (1970s-1990s), followed by a rapid expansion from 2000 to 2009, when the area occupied increased six-fold. Since 2010 its expansion has moderated, although new introductions in the Duero, Guadalquivir and Andalusian Mediterranean basins have driven localized explosive growth. Logistic and Gompertz models suggest the invasion may be approaching saturation in long-invaded basins (e.g. Ebro), projecting only a slight increase in total area occupied by 2030. However, model confidence intervals remain broad, reflecting uncertainty due to potential illegal translocations and climate-driven habitat changes in the future. Our findings underscore the urgent need for proactive management: preventing human-mediated jump dispersal, enhancing monitoring for early detection and enforcing regulations. Continued data updates and risk modelling are vital to inform policy and targeted control against this high-risk invader.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145648707","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}
Pub Date : 2025-12-01Epub Date: 2026-01-16DOI: 10.1111/jfb.70333
William Bernard Perry
{"title":"Toxic tiddlers? Mechanisms driving within species mercury levels uncovered in anchovies.","authors":"William Bernard Perry","doi":"10.1111/jfb.70333","DOIUrl":"10.1111/jfb.70333","url":null,"abstract":"","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":"1849"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145989589","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}
Pub Date : 2025-12-01Epub Date: 2025-09-02DOI: 10.1111/jfb.70208
Oscar D P Notman-Grobler, Paris M B Mastrodimitropoulos, Alessandro Bevilacqua, Robert J Lennox, Hugo Flávio
Juvenile fish play a crucial role in the health of aquatic ecosystems, serving both as the foundation for future adult populations and as a valuable food source. Studying the juvenile life stage of fish using acoustic telemetry is inherently challenging due to their small size and associated difficulties in tracking and data collection. Recent advances in telemetry, including the miniaturization of tags, have enabled researchers to investigate previously understudied size classes of fish. Tagging fish can introduce sublethal effects that alter their physiology and behaviour, ultimately biasing the collected data; this effect is exacerbated in smaller-bodied fish, which are generally more sensitive to tagging procedures. Our study tested whether tagging juvenile brook trout (Salvelinus fontinalis) of two size classes (10-12 and 13-16 cm fork length, n = 80) with a LOTEK JSATS PinTag (0.22 g, mean tag burden 1.11% of body mass, range 0.54-2.00%) impacted their oxygen consumption rates ( ) over the 2 days following tagging. Handling and tagging caused no mortalities, although we observed a nearly significant effect (p = 0.06) of the experimental group (control, anaesthesia, surgery, tagged) on standard metabolic rate (SMR). This was driven by a 7% decrease in the SMR of the tagged animals, which were significantly different from the control group when compared directly (p = 0.02). This marginal effect in standard metabolic rate, combined with the absence of significant effects on maximum metabolic rate, aerobic scope and post-exercise recovery, suggests that the JSATS PinTag does not impair the aerobic metabolic capacity of fish of this size. Our findings indicate that neither the surgery procedure nor the presence of the tag limit the brook trout's capacity for burst movement, which is highly relevant for predator-evasion responses after release in the wild. In addition, we evaluated wound recovery and suture retention over a 3-week period using either braided or monofilament suture material. While braided sutures caused more immediate irritation and were more prone to fungal growth, their quicker expulsion may reduce long-term discomfort compared to monofilament sutures. Determining the optimal suture type may ultimately depend on study duration and objectives, and longer-term monitoring could clarify which material best supports overall healing.
幼鱼在水生生态系统的健康中发挥着至关重要的作用,既是未来成年种群的基础,也是宝贵的食物来源。由于鱼类体积小,跟踪和数据收集困难,利用声波遥测技术研究鱼类的幼年生命阶段本身就具有挑战性。遥测技术的最新进展,包括标签的小型化,使研究人员能够调查以前未被充分研究的鱼类大小类别。给鱼贴上标签会带来亚致死效应,改变它们的生理和行为,最终使收集到的数据产生偏差;这种影响在体型较小的鱼类中更为严重,它们通常对标签程序更敏感。本研究测试了是否使用LOTEK JSATS PinTag (0.22 g,平均标签负荷1.11)标记两个大小类别(叉长10-12和13-16 cm, n = 80)的鳟鱼幼鱼(Salvelinus fontinalis)% of body mass, range 0.54-2.00%) impacted their oxygen consumption rates ( M ̇ O 2 $$ {dot{M}}_{{mathrm{O}}_2} $$ ) over the 2 days following tagging. Handling and tagging caused no mortalities, although we observed a nearly significant effect (p = 0.06) of the experimental group (control, anaesthesia, surgery, tagged) on standard metabolic rate (SMR). This was driven by a 7% decrease in the SMR of the tagged animals, which were significantly different from the control group when compared directly (p = 0.02). This marginal effect in standard metabolic rate, combined with the absence of significant effects on maximum metabolic rate, aerobic scope and post-exercise recovery, suggests that the JSATS PinTag does not impair the aerobic metabolic capacity of fish of this size. Our findings indicate that neither the surgery procedure nor the presence of the tag limit the brook trout's capacity for burst movement, which is highly relevant for predator-evasion responses after release in the wild. In addition, we evaluated wound recovery and suture retention over a 3-week period using either braided or monofilament suture material. While braided sutures caused more immediate irritation and were more prone to fungal growth, their quicker expulsion may reduce long-term discomfort compared to monofilament sutures. Determining the optimal suture type may ultimately depend on study duration and objectives, and longer-term monitoring could clarify which material best supports overall healing.
{"title":"Assessing metabolic rate and post-tagging recovery in juvenile fish.","authors":"Oscar D P Notman-Grobler, Paris M B Mastrodimitropoulos, Alessandro Bevilacqua, Robert J Lennox, Hugo Flávio","doi":"10.1111/jfb.70208","DOIUrl":"10.1111/jfb.70208","url":null,"abstract":"<p><p>Juvenile fish play a crucial role in the health of aquatic ecosystems, serving both as the foundation for future adult populations and as a valuable food source. Studying the juvenile life stage of fish using acoustic telemetry is inherently challenging due to their small size and associated difficulties in tracking and data collection. Recent advances in telemetry, including the miniaturization of tags, have enabled researchers to investigate previously understudied size classes of fish. Tagging fish can introduce sublethal effects that alter their physiology and behaviour, ultimately biasing the collected data; this effect is exacerbated in smaller-bodied fish, which are generally more sensitive to tagging procedures. Our study tested whether tagging juvenile brook trout (Salvelinus fontinalis) of two size classes (10-12 and 13-16 cm fork length, n = 80) with a LOTEK JSATS PinTag (0.22 g, mean tag burden 1.11% of body mass, range 0.54-2.00%) impacted their oxygen consumption rates ( <math> <mrow> <msub><mover><mi>M</mi> <mo>̇</mo></mover> <msub><mi>O</mi> <mn>2</mn></msub> </msub> </mrow> </math> ) over the 2 days following tagging. Handling and tagging caused no mortalities, although we observed a nearly significant effect (p = 0.06) of the experimental group (control, anaesthesia, surgery, tagged) on standard metabolic rate (SMR). This was driven by a 7% decrease in the SMR of the tagged animals, which were significantly different from the control group when compared directly (p = 0.02). This marginal effect in standard metabolic rate, combined with the absence of significant effects on maximum metabolic rate, aerobic scope and post-exercise recovery, suggests that the JSATS PinTag does not impair the aerobic metabolic capacity of fish of this size. Our findings indicate that neither the surgery procedure nor the presence of the tag limit the brook trout's capacity for burst movement, which is highly relevant for predator-evasion responses after release in the wild. In addition, we evaluated wound recovery and suture retention over a 3-week period using either braided or monofilament suture material. While braided sutures caused more immediate irritation and were more prone to fungal growth, their quicker expulsion may reduce long-term discomfort compared to monofilament sutures. Determining the optimal suture type may ultimately depend on study duration and objectives, and longer-term monitoring could clarify which material best supports overall healing.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":"2034-2045"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12861838/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144956802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01Epub Date: 2025-08-21DOI: 10.1111/jfb.70196
Jack Sagumai, Rebecca H Samuel, William T White, Michael I Grant
A recent survey of artisanal and subsistence fishers in Madang, Papua New Guinea, resulted in rediscovery of the sailback houndshark Gogolia filewoodi. The five females and one male G. filewoodi recorded in 2020 and 2022 near the Gogol River mouth are the first verified records of this species since its description from a single specimen in the 1970s. Gogolia is a monotypic triakid genus and thus represents a unique evolutionary lineage not seen anywhere else in the world and could be an important marine biodiversity icon for Papua New Guinea.
{"title":"Rediscovery of one of the world's rarest sharks, the sailback houndshark Gogolia filewoodi, in Papua New Guinea.","authors":"Jack Sagumai, Rebecca H Samuel, William T White, Michael I Grant","doi":"10.1111/jfb.70196","DOIUrl":"10.1111/jfb.70196","url":null,"abstract":"<p><p>A recent survey of artisanal and subsistence fishers in Madang, Papua New Guinea, resulted in rediscovery of the sailback houndshark Gogolia filewoodi. The five females and one male G. filewoodi recorded in 2020 and 2022 near the Gogol River mouth are the first verified records of this species since its description from a single specimen in the 1970s. Gogolia is a monotypic triakid genus and thus represents a unique evolutionary lineage not seen anywhere else in the world and could be an important marine biodiversity icon for Papua New Guinea.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":"107 6","pages":"2143-2145"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12861828/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146100253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01Epub Date: 2025-08-28DOI: 10.1111/jfb.70199
Zaoya Zhao, Ling Wang, Yanjin Chen, Jinyu Liu, Qianxing Zou, Shuyu Han, Yi Yi, Jingu Shi
Deterioration of water quality, especially low dissolved oxygen, has contributed to outbreaks of streptococcal disease in tilapia. It has been reported that hypoxia increases the mortality of tilapia during Streptococcus agalactiae infection. However, the underlying mechanism of the increased susceptibility of tilapia to S. agalactiae caused by hypoxia remains unknown. In this study, the pathological effects of hypoxia and S. agalactiae co-exposure in the liver of tilapia were investigated using transcriptome and metabolome analyses. When subjected to individual hypoxia or S. agalactiae exposure, the liver of tilapia exhibited significant pathological effects, including vacuolation, severe necrosis, nuclear and cellular polymorphism, hemocyte infiltration/leakage and abundant granular deposits. Moreover, these pathological effects became more severe under hypoxia and S. agalactiae co-exposure. In addition, S. agalactiae exposure increased inflammation-related gene expression, including CC1, CC2, IL-1β, TNFα, but this effect was suppressed by hypoxia. Transcriptomic analysis revealed that carbohydrate, lipid and amino acid metabolic pathways were significantly altered in the hypoxia and S. agalactiae co-exposure group compared to those in the control group. Among these metabolic pathways, only lipid metabolism was obviously altered at the metabolite level, as revealed by metabolomics analysis. Further combined analysis of the transcriptome and metabolome suggested that, in lipid metabolic pathways, glycerophospholipid metabolism should be a key pathway in S. agalactiae-infected tilapia under hypoxic conditions. Taken together, the results of the combined analysis of the global changes in the transcriptome and metabolome of the tilapia liver under hypoxia and S. agalactiae co-exposure revealed important metabolic pathways involved in the pathological process by which hypoxia increases the susceptibility of tilapia to S. agalactiae.
{"title":"Combined transcriptome and metabolome analysis of tilapia response to hypoxia and Streptococcus agalactiae co-exposure.","authors":"Zaoya Zhao, Ling Wang, Yanjin Chen, Jinyu Liu, Qianxing Zou, Shuyu Han, Yi Yi, Jingu Shi","doi":"10.1111/jfb.70199","DOIUrl":"10.1111/jfb.70199","url":null,"abstract":"<p><p>Deterioration of water quality, especially low dissolved oxygen, has contributed to outbreaks of streptococcal disease in tilapia. It has been reported that hypoxia increases the mortality of tilapia during Streptococcus agalactiae infection. However, the underlying mechanism of the increased susceptibility of tilapia to S. agalactiae caused by hypoxia remains unknown. In this study, the pathological effects of hypoxia and S. agalactiae co-exposure in the liver of tilapia were investigated using transcriptome and metabolome analyses. When subjected to individual hypoxia or S. agalactiae exposure, the liver of tilapia exhibited significant pathological effects, including vacuolation, severe necrosis, nuclear and cellular polymorphism, hemocyte infiltration/leakage and abundant granular deposits. Moreover, these pathological effects became more severe under hypoxia and S. agalactiae co-exposure. In addition, S. agalactiae exposure increased inflammation-related gene expression, including CC1, CC2, IL-1β, TNFα, but this effect was suppressed by hypoxia. Transcriptomic analysis revealed that carbohydrate, lipid and amino acid metabolic pathways were significantly altered in the hypoxia and S. agalactiae co-exposure group compared to those in the control group. Among these metabolic pathways, only lipid metabolism was obviously altered at the metabolite level, as revealed by metabolomics analysis. Further combined analysis of the transcriptome and metabolome suggested that, in lipid metabolic pathways, glycerophospholipid metabolism should be a key pathway in S. agalactiae-infected tilapia under hypoxic conditions. Taken together, the results of the combined analysis of the global changes in the transcriptome and metabolome of the tilapia liver under hypoxia and S. agalactiae co-exposure revealed important metabolic pathways involved in the pathological process by which hypoxia increases the susceptibility of tilapia to S. agalactiae.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":"2005-2021"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144956664","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}
Pub Date : 2025-12-01Epub Date: 2025-08-14DOI: 10.1111/jfb.70181
Jesse M Lepak, Adam G Hansen, Terra L Martinez, Elizabeth A Stewart, Dakotah J Pinkus, Aubrey M Pelletier, Andrew J Treble
Invasive bighead carp Hypophthalmichthys nobilis have spread throughout the Mississippi River basin, negatively impacting ecosystems. We used a remnant population (32 years after stocking) to better understand H. nobilis. We observed high annual survival (>95%), but growth was relatively slow. Lapilli otolith sections were reliable aging structures but underestimated H. nobilis age by ~10%. Dorsal-fin rays and postcleithra also showed some promise for age interpretation. This study provides information about exceptionally old H. nobilis, with unique survival, growth and habitat conditions that could further inform invasion models.
{"title":"Maximum age of bighead carp Hypophthalmichthys nobilis exceeds 30 years: Implications for anticipating invasive species establishment and impacts.","authors":"Jesse M Lepak, Adam G Hansen, Terra L Martinez, Elizabeth A Stewart, Dakotah J Pinkus, Aubrey M Pelletier, Andrew J Treble","doi":"10.1111/jfb.70181","DOIUrl":"10.1111/jfb.70181","url":null,"abstract":"<p><p>Invasive bighead carp Hypophthalmichthys nobilis have spread throughout the Mississippi River basin, negatively impacting ecosystems. We used a remnant population (32 years after stocking) to better understand H. nobilis. We observed high annual survival (>95%), but growth was relatively slow. Lapilli otolith sections were reliable aging structures but underestimated H. nobilis age by ~10%. Dorsal-fin rays and postcleithra also showed some promise for age interpretation. This study provides information about exceptionally old H. nobilis, with unique survival, growth and habitat conditions that could further inform invasion models.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":"107 6","pages":"2135-2142"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12861825/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146100214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01Epub Date: 2025-09-05DOI: 10.1111/jfb.70222
Guillermo Figueroa-Muñoz, Christina A Murphy, Ivan Arismendi, Martín Laporta, Graciela Fabiano, Tomás Chalde, Javier E Ciancio, Cecilia Y Di Prinzio, J Andres Olivos, Daniel Gomez-Uchida
{"title":"Comment on \"Multiple tools to investigate the origin of the exotic species Chinook salmon Oncorhynchus tshawytscha (Walbaum, 1792) (Salmonidae) in the world's largest chocked coastal lagoon (Gowert et al., 2025)\".","authors":"Guillermo Figueroa-Muñoz, Christina A Murphy, Ivan Arismendi, Martín Laporta, Graciela Fabiano, Tomás Chalde, Javier E Ciancio, Cecilia Y Di Prinzio, J Andres Olivos, Daniel Gomez-Uchida","doi":"10.1111/jfb.70222","DOIUrl":"10.1111/jfb.70222","url":null,"abstract":"","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":"1850-1851"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145000711","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}
Pub Date : 2025-12-01Epub Date: 2025-08-27DOI: 10.1111/jfb.70200
Heather Barnes, Mariah A Dougherty, Brandon C Vera, Jason A Kaufman
Alarm substance (AS) is widely used in zebrafish (Danio rerio, Hamilton, 1822) antipredator research to elicit an alarm reaction. This alarm reaction consists of stereotypical behaviours, including freezing, erratic swimming and a tendency to dwell at the bottom of the tank (geotaxis). Because the active compound in AS is known to degrade rapidly, many investigators choose to freeze AS until use, whereas others argue for collecting AS freshly the morning of an experimental session. As part of efforts to reduce the number of donor fish necessary for an experiment, we sought to investigate whether AS maintained overnight under cold storage could elicit an equivalent alarm response to AS of equivalent dilution collected freshly. Our results indicate that exposure to AS stored overnight at -20°C elicited a diminished alarm response compared to fresh AS of equivalent dilution. Although frozen AS may still be sufficient for many studies, our results suggest that AS is most potent when collected fresh the morning of experimentation.
{"title":"Cold storage of alarm substance reduces the behavioural stress response of zebrafish (Danio rerio).","authors":"Heather Barnes, Mariah A Dougherty, Brandon C Vera, Jason A Kaufman","doi":"10.1111/jfb.70200","DOIUrl":"10.1111/jfb.70200","url":null,"abstract":"<p><p>Alarm substance (AS) is widely used in zebrafish (Danio rerio, Hamilton, 1822) antipredator research to elicit an alarm reaction. This alarm reaction consists of stereotypical behaviours, including freezing, erratic swimming and a tendency to dwell at the bottom of the tank (geotaxis). Because the active compound in AS is known to degrade rapidly, many investigators choose to freeze AS until use, whereas others argue for collecting AS freshly the morning of an experimental session. As part of efforts to reduce the number of donor fish necessary for an experiment, we sought to investigate whether AS maintained overnight under cold storage could elicit an equivalent alarm response to AS of equivalent dilution collected freshly. Our results indicate that exposure to AS stored overnight at -20°C elicited a diminished alarm response compared to fresh AS of equivalent dilution. Although frozen AS may still be sufficient for many studies, our results suggest that AS is most potent when collected fresh the morning of experimentation.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":"2151-2159"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144956620","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}
Japanese anchovy (Engraulis japonicus) is a small pelagic fish that is frequently targeted by commercial fisheries. Japanese anchovy plays a crucial role as a vital link between primary and higher-order consumers. The elemental mercury in Japanese anchovy muscles easily bioaccumulates and is transmitted to top predators. We investigated the variation in the diets and mercury accumulation of Japanese anchovy in the high seas of the northwestern Pacific Ocean. We measured the amounts of mercury and fatty acids in the muscles of 149 Japanese anchovy specimens that were obtained from the open seas of the northwestern Pacific Ocean (39°2' N ~ 42°30' N, 154°02' E ~ 161°29' E) between June and July 2021. The results revealed that the monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) contents significantly decreased and then increased with the growth of Japanese anchovy (p < 0.001). The standard ellipse-corrected area (SEAc) calculated from the fatty acid profiles showed a decreasing and subsequently increasing pattern with anchovy growth. Trophic niche overlap reflects the degree of overlap in diet composition among species. Compared to the niche overlap among the 91-105, 106-120 and 121-135 mm groups, the niche overlap of Japanese anchovy between the 121-135 and 136-150 mm groups was lower. This change may indicate a dietary shift in Japanese anchovy with a body length of 120 mm. Mercury levels were positively correlated with C22:6n3, C20:4n6 and C20:1n9 contents and negatively correlated with C16:1n7 contents. We suggest that the proportion of higher-trophic zooplankton in the diet increased with the growth of Japanese anchovy, and that zooplankton was likely an important cause of the increase in mercury levels.
日本凤尾鱼(Engraulis japonicus)是一种小型的远洋鱼类,经常被商业渔业所瞄准。日本凤尾鱼在初级消费者和高级消费者之间起着至关重要的作用。日本凤尾鱼肌肉中的元素汞很容易生物积累并传播给顶级捕食者。我们研究了西北太平洋公海日本凤尾鱼的饮食变化和汞积累。我们测量了2021年6月至7月期间从西北太平洋公海(39°2' N ~ 42°30' N, 154°02' E ~ 161°29' E)获得的149条日本凤尾鱼标本肌肉中的汞和脂肪酸含量。结果表明:随着日本凤尾鱼的生长,单不饱和脂肪酸(MUFA)和多不饱和脂肪酸(PUFA)含量先降低后升高
{"title":"Ontogenetic niche segregation and its implications for mercury levels in Japanese anchovy from the high seas of the northwestern Pacific Ocean as revealed by fatty acid analysis.","authors":"Long Chen, Zhenfang Zhao, Guanyu Hu, Liling Zhang, Bilin Liu, Xinjun Chen","doi":"10.1111/jfb.70175","DOIUrl":"10.1111/jfb.70175","url":null,"abstract":"<p><p>Japanese anchovy (Engraulis japonicus) is a small pelagic fish that is frequently targeted by commercial fisheries. Japanese anchovy plays a crucial role as a vital link between primary and higher-order consumers. The elemental mercury in Japanese anchovy muscles easily bioaccumulates and is transmitted to top predators. We investigated the variation in the diets and mercury accumulation of Japanese anchovy in the high seas of the northwestern Pacific Ocean. We measured the amounts of mercury and fatty acids in the muscles of 149 Japanese anchovy specimens that were obtained from the open seas of the northwestern Pacific Ocean (39°2' N ~ 42°30' N, 154°02' E ~ 161°29' E) between June and July 2021. The results revealed that the monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) contents significantly decreased and then increased with the growth of Japanese anchovy (p < 0.001). The standard ellipse-corrected area (SEAc) calculated from the fatty acid profiles showed a decreasing and subsequently increasing pattern with anchovy growth. Trophic niche overlap reflects the degree of overlap in diet composition among species. Compared to the niche overlap among the 91-105, 106-120 and 121-135 mm groups, the niche overlap of Japanese anchovy between the 121-135 and 136-150 mm groups was lower. This change may indicate a dietary shift in Japanese anchovy with a body length of 120 mm. Mercury levels were positively correlated with C22:6n3, C20:4n6 and C20:1n9 contents and negatively correlated with C16:1n7 contents. We suggest that the proportion of higher-trophic zooplankton in the diet increased with the growth of Japanese anchovy, and that zooplankton was likely an important cause of the increase in mercury levels.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":"1923-1932"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144956585","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}