Pub Date : 2024-09-12DOI: 10.1007/s11160-024-09893-9
M. Virgili, A. Petetta, B. Herrmann, K. Cerbule, S. Guicciardi, G. La Manna, L. Malvarosa, D. Li Veli, G. Barone, A. Lucchetti
Small-scale coastal fisheries in the Mediterranean often employ gillnets, a widely used gear worldwide. The disadvantages of gillnets in this fishery include high bycatch levels of unwanted species and consequent discards. Moreover, spatial conflict with other gears and dolphin depredation often results in considerable economic loss. Alternative fishing methods are being tested. This study investigated whether, in small-scale fisheries in the Adriatic Sea, pots can ensure sustainable harvest of mantis shrimp (Squilla mantis), a major target demersal species in terms of landings, and possibly replace traditional gillnets. We adopted a multidisciplinary approach to investigate the catch efficiency, biological impact, and socio-economic effects of the two fishing methods. We found different species compositions in gillnet and pot catches. Gillnets yielded a greater number of discarded species of no commercial value, whereas pots caught a greater amount of mantis shrimp. Finally, a profit analysis indicated that pot fishery has the potential to increase profits for the commercial fishing industry. This study suggests that pots provide a more sustainable fishing method, both in terms of revenue and environmental impact.
{"title":"Can pots be an alternative fishing gear to gillnets? A Mediterranean case study","authors":"M. Virgili, A. Petetta, B. Herrmann, K. Cerbule, S. Guicciardi, G. La Manna, L. Malvarosa, D. Li Veli, G. Barone, A. Lucchetti","doi":"10.1007/s11160-024-09893-9","DOIUrl":"https://doi.org/10.1007/s11160-024-09893-9","url":null,"abstract":"<p>Small-scale coastal fisheries in the Mediterranean often employ gillnets, a widely used gear worldwide. The disadvantages of gillnets in this fishery include high bycatch levels of unwanted species and consequent discards. Moreover, spatial conflict with other gears and dolphin depredation often results in considerable economic loss. Alternative fishing methods are being tested. This study investigated whether, in small-scale fisheries in the Adriatic Sea, pots can ensure sustainable harvest of mantis shrimp (<i>Squilla mantis</i>), a major target demersal species in terms of landings, and possibly replace traditional gillnets. We adopted a multidisciplinary approach to investigate the catch efficiency, biological impact, and socio-economic effects of the two fishing methods. We found different species compositions in gillnet and pot catches. Gillnets yielded a greater number of discarded species of no commercial value, whereas pots caught a greater amount of mantis shrimp. Finally, a profit analysis indicated that pot fishery has the potential to increase profits for the commercial fishing industry. This study suggests that pots provide a more sustainable fishing method, both in terms of revenue and environmental impact.</p>","PeriodicalId":21181,"journal":{"name":"Reviews in Fish Biology and Fisheries","volume":"327 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142214541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2024-09-10DOI: 10.1007/s11160-024-09887-7
James Kho, Daniel E. Ruzzante
Abstract
The incorporation of epigenetics (i.e., change in gene activity without change in DNA sequence) into studies of gene regulation and phenotypic expression has contributed to a significant improvement in our understanding of the evolution of life history traits. One important epigenetic mechanism is DNA methylation, which in vertebrates generally means the addition of a methyl group to a cytosine thus altering gene expression. Here, we discuss progress and gaps in our knowledge of the role of DNA methylation in facilitating diversity across four life history trait classes in fishes: developmental processes, size and growth rates, aging and sexual maturity, and sex regulation. We discuss insights into the regulatory aspect of gene expression in fish which can ultimately influence phenotypic diversity and speciation. We discuss how temperature influences methylation patterns affecting multiple traits. DNA methylation influence on gene expression varies depending on tissue types and the location within the genome of the methylated site (i.e., DNA methylation can increase or decrease gene expression). The role of DNA methyltransferases is also a common denominator across all tissue types in influencing the global methylome status regardless of species or environmental stressor. Organismal development stage is equally important, a decrease in global methylation throughout early development generally corresponds to elevated gene expression associated with growth and development. Finally, we discuss general limitations of DNA methylation studies with a focus on fish. We then provide recommendations for future research.
Graphical abstract
摘要 将表观遗传学(即在不改变 DNA 序列的情况下改变基因活性)纳入基因调控和表型表达的研究,大大提高了我们对生活史性状进化的认识。DNA甲基化是一种重要的表观遗传机制,在脊椎动物中,甲基化通常意味着在胞嘧啶上添加一个甲基,从而改变基因的表达。在这里,我们将讨论 DNA 甲基化在促进鱼类四类生活史性状多样性方面的作用所取得的进展和存在的差距:发育过程、体型和生长率、衰老和性成熟以及性别调控。我们讨论了对鱼类基因表达调控方面的见解,这种调控最终会影响表型多样性和物种分化。我们讨论了温度如何影响甲基化模式,从而影响多种性状。DNA 甲基化对基因表达的影响因组织类型和甲基化位点在基因组中的位置而异(即 DNA 甲基化可增加或减少基因表达)。DNA 甲基转移酶的作用也是所有组织类型在影响全球甲基组状态方面的一个共同点,而与物种或环境压力无关。生物体的发育阶段也同样重要,整个早期发育过程中全球甲基化的降低通常与生长发育相关基因表达的升高相对应。最后,我们以鱼类为重点,讨论了 DNA 甲基化研究的一般局限性。然后,我们对未来的研究提出了建议。
{"title":"The role of DNA methylation in facilitating life history trait diversity in fishes","authors":"James Kho, Daniel E. Ruzzante","doi":"10.1007/s11160-024-09887-7","DOIUrl":"https://doi.org/10.1007/s11160-024-09887-7","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The incorporation of epigenetics (i.e., change in gene activity without change in DNA sequence) into studies of gene regulation and phenotypic expression has contributed to a significant improvement in our understanding of the evolution of life history traits. One important epigenetic mechanism is DNA methylation, which in vertebrates generally means the addition of a methyl group to a cytosine thus altering gene expression. Here, we discuss progress and gaps in our knowledge of the role of DNA methylation in facilitating diversity across four life history trait classes in fishes: developmental processes, size and growth rates, aging and sexual maturity, and sex regulation. We discuss insights into the regulatory aspect of gene expression in fish which can ultimately influence phenotypic diversity and speciation. We discuss how temperature influences methylation patterns affecting multiple traits. DNA methylation influence on gene expression varies depending on tissue types and the location within the genome of the methylated site (i.e., DNA methylation can increase or decrease gene expression). The role of DNA methyltransferases is also a common denominator across all tissue types in influencing the global methylome status regardless of species or environmental stressor. Organismal development stage is equally important, a decrease in global methylation throughout early development generally corresponds to elevated gene expression associated with growth and development. Finally, we discuss general limitations of DNA methylation studies with a focus on fish. We then provide recommendations for future research.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>","PeriodicalId":21181,"journal":{"name":"Reviews in Fish Biology and Fisheries","volume":"5 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142214539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2024-09-10DOI: 10.1007/s11160-024-09892-w
Rose E. Stuart, Jason D. Stockwell, J. Ellen Marsden
Freshwater eels (Anguillidae) are facing numerous anthropogenic impacts that have led to declines in abundance for nearly all species. They have a complex life history that includes obligate migration and flexible habitat use, characteristics which have generated much research interest in the family. Eels also have high cultural and economic value, further incentivizing the study of key species. We reviewed the scientific literature on anguillids from the last four decades, analyzing research trends among and within species of the genus Anguilla. We identified a shift in research focus from largely biological towards more applied management and conservation topics, an increased emphasis on migration and fish passage considerations, and a tendency towards research on glass eels and silver eels over other life stages. We also identified a significant disparity in research effort between temperate species and tropical species, with a scarcity of knowledge on the latter. Finally, we described several key knowledge gaps about community-based interactions of eels, notably their roles as predator, prey, and ecosystem connector, and highlight opportunities for early career researchers to establish research programs within the field of anguillid research.
{"title":"Anguillids: widely studied yet poorly understood—a literature review of the current state of Anguilla eel research","authors":"Rose E. Stuart, Jason D. Stockwell, J. Ellen Marsden","doi":"10.1007/s11160-024-09892-w","DOIUrl":"https://doi.org/10.1007/s11160-024-09892-w","url":null,"abstract":"<p>Freshwater eels (Anguillidae) are facing numerous anthropogenic impacts that have led to declines in abundance for nearly all species. They have a complex life history that includes obligate migration and flexible habitat use, characteristics which have generated much research interest in the family. Eels also have high cultural and economic value, further incentivizing the study of key species. We reviewed the scientific literature on anguillids from the last four decades, analyzing research trends among and within species of the genus <i>Anguilla</i>. We identified a shift in research focus from largely biological towards more applied management and conservation topics, an increased emphasis on migration and fish passage considerations, and a tendency towards research on glass eels and silver eels over other life stages. We also identified a significant disparity in research effort between temperate species and tropical species, with a scarcity of knowledge on the latter. Finally, we described several key knowledge gaps about community-based interactions of eels, notably their roles as predator, prey, and ecosystem connector, and highlight opportunities for early career researchers to establish research programs within the field of anguillid research.</p>","PeriodicalId":21181,"journal":{"name":"Reviews in Fish Biology and Fisheries","volume":"13 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142214540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2024-09-05DOI: 10.1007/s11160-024-09883-x
Diana Paula Perin, Denise Felicetti Máh, Chrystian Aparecido Grillo Haerter, Sandro Tonello, Amanda de Souza Machado, Leonardo Marcel Paiz, Maelin da Silva, Luciana Borowski Pietricoski, Dalila Moter Benvegnú, Vladimir Pavan Margarido, Daniel Rodrigues Blanco, Roberto Laridondo Lui
Abstract
The Hoplias malabaricus group comprises seven described species, including seven karyomorphs for H. malabaricus. However, the relationship between morphological and chromosomal data within the group remains unresolved. Most studies on the Hoplias malabaricus group from the Iguazu River ecoregion have primarily focused on its upper and middle sections, while the lower Iguazu River remains unstudied. Therefore, in this study, we investigated a population of H. malabaricus from the Capanema’s River (lower Iguazu River basin), Brazil, using cytogenetic techniques and DNA barcode. Through these analyses, we identified the karyomorphs A and D living in sympatry in the lower Iguazu River basin. The karyomorph A, identified as native to the Iguazu River basin, had two cytotypes, designated as A1 and A2, which are differentiated by C-positive heterochromatin and rDNA distribution patterns. Conversely, this is the first record of karyomorph D for the Iguazu River basin, which was previously thought to be endemic to the Upper Paraná River basin and may therefore represent an introduced karyomorph. Interestingly, the cytotype A2 is very similar (same haplogroup) to sequences of Hoplias argentinensis, while the karyomorph D from the lower Iguazu River basin is similar to sequences identified as Hoplias misionera. These findings provided new insights into the diversity of Hoplias gr. malabaricus from the Neotropical region, achieved through cytogenetic and DNA barcode integration. The results also highlight the increased conservation risk for native species in the Iguazu River ecoregion, particularly considering the ecological position occupied by trahiras within the trophic levels.
Graphical abstract
摘要Hoplias malabaricus群包括7个已描述的物种,其中H. malabaricus有7个核果形态。然而,该类群中形态学和染色体数据之间的关系仍未得到解决。对伊瓜苏河生态区域中马拉巴里亚蛇(Hoplias malabaricus)类群的大多数研究主要集中在伊瓜苏河中上游河段,而对伊瓜苏河下游河段的研究仍然空白。因此,在这项研究中,我们利用细胞遗传学技术和 DNA 条形码,对巴西卡帕内马河(伊瓜苏河下游流域)的一个马拉巴里亚 H. 种群进行了调查。通过这些分析,我们确定了在伊瓜苏河下游流域共生的核果 A 和 D。被确认为原产于伊瓜苏河流域的核果 A 有两个细胞型,分别被命名为 A1 和 A2,它们通过 C 阳性异染色质和 rDNA 分布模式进行区分。与此相反,这是伊瓜苏河流域首次记录到核果形态 D,该核果形态以前被认为是上巴拉那河流域的特有物种,因此可能是一种引入的核果形态。有趣的是,细胞型 A2 与阿根廷霍普利亚斯(Hoplias argentinensis)的序列非常相似(单倍群相同),而伊瓜苏河流域下游的核果 D 则与被鉴定为霍普利亚斯-米西奥内拉(Hoplias misionera)的序列相似。通过细胞遗传学和 DNA 条形码整合,这些发现为深入了解新热带地区马拉巴里亚霍普利亚种的多样性提供了新的视角。研究结果还强调了伊瓜苏河生态区本地物种面临的更大的保护风险,特别是考虑到特拉希拉在营养级中占据的生态地位。
{"title":"Cytogenetics and DNA barcode in Hoplias gr. malabaricus (Characiformes, Erythrinidae) reveals correlation between karyomorphs and valid species","authors":"Diana Paula Perin, Denise Felicetti Máh, Chrystian Aparecido Grillo Haerter, Sandro Tonello, Amanda de Souza Machado, Leonardo Marcel Paiz, Maelin da Silva, Luciana Borowski Pietricoski, Dalila Moter Benvegnú, Vladimir Pavan Margarido, Daniel Rodrigues Blanco, Roberto Laridondo Lui","doi":"10.1007/s11160-024-09883-x","DOIUrl":"https://doi.org/10.1007/s11160-024-09883-x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The <i>Hoplias malabaricus</i> group comprises seven described species, including seven karyomorphs for <i>H. malabaricus</i>. However, the relationship between morphological and chromosomal data within the group remains unresolved. Most studies on the <i>Hoplias malabaricus</i> group from the Iguazu River ecoregion have primarily focused on its upper and middle sections, while the lower Iguazu River remains unstudied. Therefore, in this study, we investigated a population of <i>H. malabaricus</i> from the Capanema’s River (lower Iguazu River basin), Brazil, using cytogenetic techniques and DNA barcode. Through these analyses, we identified the karyomorphs A and D living in sympatry in the lower Iguazu River basin. The karyomorph A, identified as native to the Iguazu River basin, had two cytotypes, designated as A1 and A2, which are differentiated by C-positive heterochromatin and rDNA distribution patterns. Conversely, this is the first record of karyomorph D for the Iguazu River basin, which was previously thought to be endemic to the Upper Paraná River basin and may therefore represent an introduced karyomorph. Interestingly, the cytotype A2 is very similar (same haplogroup) to sequences of <i>Hoplias argentinensis</i>, while the karyomorph D from the lower Iguazu River basin is similar to sequences identified as <i>Hoplias misionera</i>. These findings provided new insights into the diversity of <i>Hoplias</i> gr. <i>malabaricus</i> from the Neotropical region, achieved through cytogenetic and DNA barcode integration. The results also highlight the increased conservation risk for native species in the Iguazu River ecoregion, particularly considering the ecological position occupied by trahiras within the trophic levels.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>\u0000","PeriodicalId":21181,"journal":{"name":"Reviews in Fish Biology and Fisheries","volume":"78 2 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142214568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2024-08-29DOI: 10.1007/s11160-024-09889-5
Jesse Brinkhof, Manu Sistiaga, Bent Herrmann, Junita D. Karlsen, Eduardo Grimaldo, Nadine Jacques, Zita Bak-Jensen
Fish behavior is important to consider when developing selective fishing gear. In studies designed to investigate the size selective properties of towed fishing gears such as trawls, fish behavior is mainly documented by underwater video recordings. Because fishing gear can be operated at great depths or in other low light environments, artificial light is often required for underwater recordings. However, artificial light can influence fish behavior, which casts doubt on the validity of behavioral observations obtained in the presence of artificial light. However, removing artificial light disables video recordings and the possibility to study fish behavior in relation to selectivity devices towed fishing gears in low light environments. To date, little is known about the extent to which artificial light used for video observations affects fish behavior with respect to fishing gear. Therefore, we conducted fishing trials in the Barents Sea demersal trawl fishery to assess the effect of light sources on fish behavior by using size selectivity results in towed fishing gears. We found that the behavior of cod (Gadus morhua) was unaffected by the light sources, whereas the behavior of haddock (Melanogrammus aeglefinus), saithe (Pollachius virens) and redfish (Sebastes spp.) significantly changed when red light and white light were employed. Our results also demonstrated significant differences in fish behavior between white and red light.
{"title":"Observing fish behavior in towed fishing gear—is there an influence of artificial light?","authors":"Jesse Brinkhof, Manu Sistiaga, Bent Herrmann, Junita D. Karlsen, Eduardo Grimaldo, Nadine Jacques, Zita Bak-Jensen","doi":"10.1007/s11160-024-09889-5","DOIUrl":"https://doi.org/10.1007/s11160-024-09889-5","url":null,"abstract":"<p>Fish behavior is important to consider when developing selective fishing gear. In studies designed to investigate the size selective properties of towed fishing gears such as trawls, fish behavior is mainly documented by underwater video recordings. Because fishing gear can be operated at great depths or in other low light environments, artificial light is often required for underwater recordings. However, artificial light can influence fish behavior, which casts doubt on the validity of behavioral observations obtained in the presence of artificial light. However, removing artificial light disables video recordings and the possibility to study fish behavior in relation to selectivity devices towed fishing gears in low light environments. To date, little is known about the extent to which artificial light used for video observations affects fish behavior with respect to fishing gear. Therefore, we conducted fishing trials in the Barents Sea demersal trawl fishery to assess the effect of light sources on fish behavior by using size selectivity results in towed fishing gears. We found that the behavior of cod (<i>Gadus morhua</i>) was unaffected by the light sources, whereas the behavior of haddock (<i>Melanogrammus aeglefinus</i>), saithe (<i>Pollachius virens</i>) and redfish (<i>Sebastes</i> spp.) significantly changed when red light and white light were employed. Our results also demonstrated significant differences in fish behavior between white and red light.</p>","PeriodicalId":21181,"journal":{"name":"Reviews in Fish Biology and Fisheries","volume":"20 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142214542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2024-08-28DOI: 10.1007/s11160-024-09888-6
Patrick J. Burke, Lauren Meyer, Vincent Raoult, Charlie Huveneers, Jane E. Williamson
Quantifying the trophic role of a species is key to understanding its ecology and ecological role. Their trophic role can influence community composition, ecosystem stability, and nutrient transport and cycling between habitats through ingestion, egestion, and excretion, which requires an understanding of species diet and habitat use. Despite the regular occurrence of sawsharks in Australian temperate fisheries, there remains limited information on their trophic ecology or habitat use, but they are assumed to be benthic consumers. We used fatty acid and stable isotope profiles along with stomach content analysis to investigate the trophic ecology of two sympatric species of sawsharks, the common sawshark (Pristiophorus cirratus) and southern sawshark (Pristiophorus nudipinnis) in south-eastern Australia. Stable isotope analysis of δ13C, δ15N, and δ34S in sawshark muscle revealed that P. nudipinnis fed at a higher trophic level than P. cirratus, and mixing models and stomach contents indicated P. nudipinnis was surprisingly reliant on pelagic and benthopelagic prey sources. In contrast, P. cirratus preyed on more benthic invertebrate species, not found in P. nudipinnis. This bentho-pelagic partitioning between species was supported by P. nudipinnis fatty acid profiles having higher levels of tracers associated with dinoflagellate basal sources (16:1/16:0, 22:6ω3) than P. cirratus, indicating a reliance on pelagic food webs. These data demonstrate that sawsharks are mesopredators that play a substantial role linking pelagic and benthic food webs and highlights the value of incorporating multiple biochemical tracers to provide a comprehensive representation of an animal’s trophic ecology and role in and between ecosystems.
量化物种的营养作用是了解其生态学和生态作用的关键。它们的营养作用可以影响群落组成、生态系统稳定性以及通过摄食、摄取和排泄实现的栖息地之间的营养运输和循环,这就需要了解物种的饮食和栖息地利用情况。尽管锯鲨经常出现在澳大利亚温带渔业中,但有关其营养生态学或栖息地利用的信息仍然有限,但它们被认为是底栖消费者。我们利用脂肪酸和稳定同位素图谱以及胃内容物分析,研究了澳大利亚东南部两种同域锯鲨--普通锯鲨(Pristiophorus cirratus)和南方锯鲨(Pristiophorus nudipinnis)的营养生态学。对锯鲨肌肉中的δ13C、δ15N和δ34S进行的稳定同位素分析表明,南方锯鲨的营养级高于普通锯鲨,混合模型和胃内容物表明南方锯鲨出人意料地依赖浮游和底栖猎物来源。相反,P. cirratus 捕食更多的底栖无脊椎动物,而 P. nudipinnis 则没有。与 P. cirratus 相比,P. nudipinnis 脂肪酸图谱中与甲藻基础来源(16:1/16:0, 22:6ω3)相关的示踪剂含量更高,这证明了物种之间的底栖-中上层分化,表明其对中上层食物网的依赖。这些数据表明,锯鲨是中层食肉动物,在连接浮游和底栖食物网方面发挥着重要作用,并强调了采用多种生化示踪剂全面反映动物营养生态学以及在生态系统中和生态系统之间的作用的价值。
{"title":"Multi-disciplinary approach identifies pelagic nutrient linkage by sawsharks","authors":"Patrick J. Burke, Lauren Meyer, Vincent Raoult, Charlie Huveneers, Jane E. Williamson","doi":"10.1007/s11160-024-09888-6","DOIUrl":"https://doi.org/10.1007/s11160-024-09888-6","url":null,"abstract":"<p>Quantifying the trophic role of a species is key to understanding its ecology and ecological role. Their trophic role can influence community composition, ecosystem stability, and nutrient transport and cycling between habitats through ingestion, egestion, and excretion, which requires an understanding of species diet and habitat use. Despite the regular occurrence of sawsharks in Australian temperate fisheries, there remains limited information on their trophic ecology or habitat use, but they are assumed to be benthic consumers. We used fatty acid and stable isotope profiles along with stomach content analysis to investigate the trophic ecology of two sympatric species of sawsharks, the common sawshark (<i>Pristiophorus cirratus</i>) and southern sawshark (<i>Pristiophorus nudipinnis</i>) in south-eastern Australia. Stable isotope analysis of δ<sup>13</sup>C, δ<sup>15</sup>N, and δ<sup>34</sup>S in sawshark muscle revealed that <i>P. nudipinnis</i> fed at a higher trophic level than <i>P. cirratus</i>, and mixing models and stomach contents indicated <i>P. nudipinnis</i> was surprisingly reliant on pelagic and benthopelagic prey sources. In contrast, <i>P. cirratus</i> preyed on more benthic invertebrate species, not found in <i>P. nudipinnis</i>. This bentho-pelagic partitioning between species was supported by <i>P. nudipinnis</i> fatty acid profiles having higher levels of tracers associated with dinoflagellate basal sources (16:1/16:0, 22:6ω3) than <i>P. cirratus</i>, indicating a reliance on pelagic food webs. These data demonstrate that sawsharks are mesopredators that play a substantial role linking pelagic and benthic food webs and highlights the value of incorporating multiple biochemical tracers to provide a comprehensive representation of an animal’s trophic ecology and role in and between ecosystems.</p>","PeriodicalId":21181,"journal":{"name":"Reviews in Fish Biology and Fisheries","volume":"97 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142214567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2024-08-27DOI: 10.1007/s11160-024-09890-y
Zhiping Feng, Nan Li, Xinjun Chen, Yunkai Li, Jie Cao, Wei Yu
In this study, the four most important species in the Humboldt Current System (HCS), Engraulis ringens, Sardinops sagax, Trachurus murphyi, and Dosidicus gigas were linked to four climate indices, sea surface temperature (SST) and wind speed (WS) based on multivariate statistical analyses, aiming to explore their nonstationary responses to climate variability. Significant decadal variations in the catches were identified, with regime shifts in the mid-1970s, early 1990s, and late 1990s. These shifts corresponded well to climatic and environment regime shifts during these periods. However, the response patterns to climate and environmental variations varied among species. Compared with other physical drivers, seawater temperature, wind speed, the Pacific Decadal Oscillation (PDO), and the North Pacific Gyre Oscillation (NPGO) had greater ecological importance in driving changes in the four pelagic species. The variations in the important climate events influenced seawater temperature and wind speed fluctuations within the HCS, impacting on these commercially important pelagic species. Furthermore, non-stationarity was identified in the relationships between climate/environment and species catches, with different species showing different threshold years. The non-stationarity may be attributed to the transitions between warm and cold periods within the HCS, as well as shifts between strong and weak phases of pressure system. This study helps further understand changes in the HCS caused by fluctuations in climate and environment.
{"title":"Nonstationary response of commercially pelagic species in the Humboldt current ecosystem to climate variability","authors":"Zhiping Feng, Nan Li, Xinjun Chen, Yunkai Li, Jie Cao, Wei Yu","doi":"10.1007/s11160-024-09890-y","DOIUrl":"https://doi.org/10.1007/s11160-024-09890-y","url":null,"abstract":"<p>In this study, the four most important species in the Humboldt Current System (HCS), <i>Engraulis ringens</i>, <i>Sardinops sagax</i>, <i>Trachurus murphyi</i>, and <i>Dosidicus gigas</i> were linked to four climate indices, sea surface temperature (SST) and wind speed (WS) based on multivariate statistical analyses, aiming to explore their nonstationary responses to climate variability. Significant decadal variations in the catches were identified, with regime shifts in the mid-1970s, early 1990s, and late 1990s. These shifts corresponded well to climatic and environment regime shifts during these periods. However, the response patterns to climate and environmental variations varied among species. Compared with other physical drivers, seawater temperature, wind speed, the Pacific Decadal Oscillation (PDO), and the North Pacific Gyre Oscillation (NPGO) had greater ecological importance in driving changes in the four pelagic species. The variations in the important climate events influenced seawater temperature and wind speed fluctuations within the HCS, impacting on these commercially important pelagic species. Furthermore, non-stationarity was identified in the relationships between climate/environment and species catches, with different species showing different threshold years. The non-stationarity may be attributed to the transitions between warm and cold periods within the HCS, as well as shifts between strong and weak phases of pressure system. This study helps further understand changes in the HCS caused by fluctuations in climate and environment.</p>","PeriodicalId":21181,"journal":{"name":"Reviews in Fish Biology and Fisheries","volume":"97 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142214563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2024-08-19DOI: 10.1007/s11160-024-09871-1
Georg H. Engelhard, Chris Bova, M. Natanah C. Gusha, Olivia L. Harrod, Timoteus Kadhila, Alex Kanyimba, Usman Khan, Anja Kreiner, Sandy Nghipangelwa, Elsemi Olwage, John K. Pinnegar, Warren Potts, Nina Rivers, Elize Shakalela, Bernadette Snow, Sirkka Tshiningayamwe, Ursula Unengu, Angelika Veii, Tapiwa V. Warikandwa, Margit R. Wilhelm, Kieran Hyder
In Namibia, fisheries are important for food security and protein provisioning, income generation and trade; but they are vulnerable to the impacts of climate change. Not only does climate change impact the marine living resources crucial to fisheries; but changes in weather, currents and storminess are affecting the safety and effectiveness of fishing. Here we ask: What are the key risks from climate change to the eight large-scale fishery sectors of Namibia, and for the recreational and small-scale (artisanal) fisheries? For each fishery sector, we assessed three main risk components: (1) climate hazard exposure; (2) fish species sensitivity; and (3) socio-economic vulnerability. In combination, these three risk components are then used to calculate the overall climate risk for each fishery. Climate hazard exposure was assessed as highest for the small-scale, recreational, and rock lobster fisheries. Species sensitivities were highest for the rock lobster and crab fisheries, followed by monkfish trawlers, hake liners and hake trawlers. Socio-economic vulnerability was highest for the small pelagic fishery (linked to the collapse of pilchard). The overall climate risk emerged as greatest for the rock lobster fishery, followed by the (highly marginalised) small-scale artisanal fishery. The key risks by sector emerging from this assessment, informed five stakeholder workshops held across Namibia in 2023, attended by representatives of each sector and aimed at exploring options for climate adaptation. Based on these, we discuss potential adaptation measures that could reduce risk and minimise consequences, in support of improved climate resilience in Namibian fisheries.
{"title":"Climate risk assessment of the fisheries in Namibia","authors":"Georg H. Engelhard, Chris Bova, M. Natanah C. Gusha, Olivia L. Harrod, Timoteus Kadhila, Alex Kanyimba, Usman Khan, Anja Kreiner, Sandy Nghipangelwa, Elsemi Olwage, John K. Pinnegar, Warren Potts, Nina Rivers, Elize Shakalela, Bernadette Snow, Sirkka Tshiningayamwe, Ursula Unengu, Angelika Veii, Tapiwa V. Warikandwa, Margit R. Wilhelm, Kieran Hyder","doi":"10.1007/s11160-024-09871-1","DOIUrl":"https://doi.org/10.1007/s11160-024-09871-1","url":null,"abstract":"<p>In Namibia, fisheries are important for food security and protein provisioning, income generation and trade; but they are vulnerable to the impacts of climate change. Not only does climate change impact the marine living resources crucial to fisheries; but changes in weather, currents and storminess are affecting the safety and effectiveness of fishing. Here we ask: What are the key risks from climate change to the eight large-scale fishery sectors of Namibia, and for the recreational and small-scale (artisanal) fisheries? For each fishery sector, we assessed three main risk components: (1) climate hazard exposure; (2) fish species sensitivity; and (3) socio-economic vulnerability. In combination, these three risk components are then used to calculate the overall climate risk for each fishery. Climate hazard exposure was assessed as highest for the small-scale, recreational, and rock lobster fisheries. Species sensitivities were highest for the rock lobster and crab fisheries, followed by monkfish trawlers, hake liners and hake trawlers. Socio-economic vulnerability was highest for the small pelagic fishery (linked to the collapse of pilchard). The overall climate risk emerged as greatest for the rock lobster fishery, followed by the (highly marginalised) small-scale artisanal fishery. The key risks by sector emerging from this assessment, informed five stakeholder workshops held across Namibia in 2023, attended by representatives of each sector and aimed at exploring options for climate adaptation. Based on these, we discuss potential adaptation measures that could reduce risk and minimise consequences, in support of improved climate resilience in Namibian fisheries.</p>","PeriodicalId":21181,"journal":{"name":"Reviews in Fish Biology and Fisheries","volume":"78 2 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142214544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2024-08-14DOI: 10.1007/s11160-024-09885-9
Joana Vasconcelos, Jose A. Sanabria-Fernandez, Víctor M. Tuset, Ricardo Sousa, Graça Faria, Rodrigo Riera
Global change has profound effects on marine species, communities, and ecosystems. Among these impacts, small pelagics have emerged as valuable indicators for detecting regime shifts in fish stocks. They exhibit swift responses to changes in ocean variables, including decreased abundances, accelerated juvenile growth rates, early maturation, and reduced adult sizes in warm waters. However, each pelagic species occupies a unique local ecological niche, that reflects the sum of all environmental conditions. Consequently, their responses to environmental changes manifest in distinct ways. We explore here how global change affects small pelagics in the Madeira Archipelago (NE Atlantic Ocean) at (i) community level, by studying the effects of climate change over a 40-year (1980–2019) period on small pelagic landings, and (ii) population level, by studying the effects on the life-history traits of the two most abundant species, Scomber colias and Trachurus picturatus. Our study demonstrated that anomalies in the Sea Surface Temperature and the North Atlantic Oscillation caused a regime shift within the small pelagic community. Both environmental predictors explained 88.9% of the community landings oscillations. S. colias appears to exhibit a relatively more favorable adaptive response to climate change compared to T. picturatus. Understanding the species-specific ecological responses of small pelagic fish to global change is crucial for effective management and conservation efforts in the face of ongoing environmental scenarios.
{"title":"Rising temperatures, falling fisheries: causes and consequences of crossing the tipping point in a small-pelagic community","authors":"Joana Vasconcelos, Jose A. Sanabria-Fernandez, Víctor M. Tuset, Ricardo Sousa, Graça Faria, Rodrigo Riera","doi":"10.1007/s11160-024-09885-9","DOIUrl":"https://doi.org/10.1007/s11160-024-09885-9","url":null,"abstract":"<p>Global change has profound effects on marine species, communities, and ecosystems. Among these impacts, small pelagics have emerged as valuable indicators for detecting regime shifts in fish stocks. They exhibit swift responses to changes in ocean variables, including decreased abundances, accelerated juvenile growth rates, early maturation, and reduced adult sizes in warm waters. However, each pelagic species occupies a unique local ecological niche, that reflects the sum of all environmental conditions. Consequently, their responses to environmental changes manifest in distinct ways. We explore here how global change affects small pelagics in the Madeira Archipelago (NE Atlantic Ocean) at (i) community level, by studying the effects of climate change over a 40-year (1980–2019) period on small pelagic landings, and (ii) population level, by studying the effects on the life-history traits of the two most abundant species, <i>Scomber colias</i> and <i>Trachurus picturatus</i>. Our study demonstrated that anomalies in the Sea Surface Temperature and the North Atlantic Oscillation caused a regime shift within the small pelagic community. Both environmental predictors explained 88.9% of the community landings oscillations. <i>S. colias</i> appears to exhibit a relatively more favorable adaptive response to climate change compared to <i>T. picturatus</i>. Understanding the species-specific ecological responses of small pelagic fish to global change is crucial for effective management and conservation efforts in the face of ongoing environmental scenarios.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>","PeriodicalId":21181,"journal":{"name":"Reviews in Fish Biology and Fisheries","volume":"97 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142214614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2024-08-07DOI: 10.1007/s11160-024-09884-w
Huangxin Liu, Pengcheng Li, Xiaoqian Leng, Ming Jiang, Li Shen, Puyuan Wang, Hui Zhang, Jiang Luo, Wei Xiong, Yuan Liu, Hao Du
The Chinese sturgeon (Acipenser sinensis) is a critically endangered, large migratory fish that serves as a vital indicator of ecological status of marine and river environments. Conservation efforts for Chinese sturgeon primarily focus on freshwater rearing, potentially leading to smaller adult sizes and higher disease incidence due to limited exposure to marine environments. Thus, it is imperative to study the behavioural characteristics and marine life history of artificially reared populations in seawater environments. In this study, acoustic telemetry technology was employed to investigate the behaviour of the Chinese sturgeon. We deployed an acoustic array at a nearshore-fenced marine farm on Bailong Island and conducted a one-year (December 2020–December 2021) tracking of ten acoustic-tagged fish, comprising five adults and five juveniles. We generated distribution heat maps and analysed displacement during typhoons and tidal events to differentiate activity levels. Annual distribution revealed areas of distinct increased density, with adults displaying a denser distribution compared to the more scattered pattern observed in juveniles. Rhythmic behaviour in response to tidal cycles was observed. During typhoon periods, individuals exhibited reduced activity levels but increased concentration, with no significant diurnal behavioral variations. These age-specific and environmentally responsive habitat preferences provide valuable supplementary insights into the species' life history and potential conservation strategies.
{"title":"Exploring the adaptive behaviour and environmental acclimation of artificially-bred Chinese sturgeon (Acipenser sinensis) in semi-open marine environment: insights for endangered species conservation","authors":"Huangxin Liu, Pengcheng Li, Xiaoqian Leng, Ming Jiang, Li Shen, Puyuan Wang, Hui Zhang, Jiang Luo, Wei Xiong, Yuan Liu, Hao Du","doi":"10.1007/s11160-024-09884-w","DOIUrl":"https://doi.org/10.1007/s11160-024-09884-w","url":null,"abstract":"<p>The Chinese sturgeon (<i>Acipenser sinensis</i>) is a critically endangered, large migratory fish that serves as a vital indicator of ecological status of marine and river environments. Conservation efforts for Chinese sturgeon primarily focus on freshwater rearing, potentially leading to smaller adult sizes and higher disease incidence due to limited exposure to marine environments. Thus, it is imperative to study the behavioural characteristics and marine life history of artificially reared populations in seawater environments. In this study, acoustic telemetry technology was employed to investigate the behaviour of the Chinese sturgeon. We deployed an acoustic array at a nearshore-fenced marine farm on Bailong Island and conducted a one-year (December 2020–December 2021) tracking of ten acoustic-tagged fish, comprising five adults and five juveniles. We generated distribution heat maps and analysed displacement during typhoons and tidal events to differentiate activity levels. Annual distribution revealed areas of distinct increased density, with adults displaying a denser distribution compared to the more scattered pattern observed in juveniles. Rhythmic behaviour in response to tidal cycles was observed. During typhoon periods, individuals exhibited reduced activity levels but increased concentration, with no significant diurnal behavioral variations. These age-specific and environmentally responsive habitat preferences provide valuable supplementary insights into the species' life history and potential conservation strategies.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\u0000","PeriodicalId":21181,"journal":{"name":"Reviews in Fish Biology and Fisheries","volume":"14 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}