Climate warming is a serious threat to many organisms, such as cold-adapted ectotherms [...]
气候变暖严重威胁着许多生物,如适应寒冷的外温动物[......]
{"title":"The Effect of Climate Change on Salmonid Fishes in Rivers","authors":"Bror Jonsson","doi":"10.3390/fishes9010029","DOIUrl":"https://doi.org/10.3390/fishes9010029","url":null,"abstract":"Climate warming is a serious threat to many organisms, such as cold-adapted ectotherms [...]","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139445451","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}
Shichen Zhao, Bin Wen, Hua Liang, Jianzhong Gao, Zai-Zhong Chen
Discus fish, Symphysodon spp., have a unique parental care strategy where the fry feed on their parents’ skin mucus after hatching. Here, lipidomics was employed to compare the skin mucus lipid profiles of male or female discus fish during parental and non-parental care. By multivariate statistical analysis, clear separations were found between parental and non-parental female and between parental and non-parental male discus. In the comparison between female discus in the parental and non-parental stages, a total of 107 differentially expressed lipids (DELs) were observed, of which 23 showed increased levels during parental care. For male discus, a total of 108 DELs were found, of which 46 displayed increased levels during parental care. The main DELs were phosphatidyl ethanolamine and phosphatidylinositol, mainly involved in arachidonic acid and sphingolipid metabolism pathways. Further, by comparing parental male and female discus, we found 47 DELs involved in the glycerophospholipid metabolism pathway. Diglyceride showed a higher concentration in the skin mucus of parental females, while phospholipids showed a higher level in that of parental males. Our results revealed changes in the skin mucus lipid profiles of discus fish during parental care, as well as sex-dependent differences between parental fish.
{"title":"Sex-Dependent Lipid Profile Differences in Skin Mucus between Non-Parental and Parental Discus Fish (Symphysodon haraldi) Determined by Lipidomics","authors":"Shichen Zhao, Bin Wen, Hua Liang, Jianzhong Gao, Zai-Zhong Chen","doi":"10.3390/fishes9010027","DOIUrl":"https://doi.org/10.3390/fishes9010027","url":null,"abstract":"Discus fish, Symphysodon spp., have a unique parental care strategy where the fry feed on their parents’ skin mucus after hatching. Here, lipidomics was employed to compare the skin mucus lipid profiles of male or female discus fish during parental and non-parental care. By multivariate statistical analysis, clear separations were found between parental and non-parental female and between parental and non-parental male discus. In the comparison between female discus in the parental and non-parental stages, a total of 107 differentially expressed lipids (DELs) were observed, of which 23 showed increased levels during parental care. For male discus, a total of 108 DELs were found, of which 46 displayed increased levels during parental care. The main DELs were phosphatidyl ethanolamine and phosphatidylinositol, mainly involved in arachidonic acid and sphingolipid metabolism pathways. Further, by comparing parental male and female discus, we found 47 DELs involved in the glycerophospholipid metabolism pathway. Diglyceride showed a higher concentration in the skin mucus of parental females, while phospholipids showed a higher level in that of parental males. Our results revealed changes in the skin mucus lipid profiles of discus fish during parental care, as well as sex-dependent differences between parental fish.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448664","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}
Yiqian Xu, Junren Xue, Hongbo Liu, T. Jiang, Xiubao Chen, Jian Yang
To confirm whether Chinese mitten crabs (Eriocheir sinensis), commonly known as hairy crabs or river crabs, in non-Yangcheng Lake areas undergo morphological convergence with the original crabs in the Yangcheng Lake purse seine and high-standard modified aquaculture ponds after being “introduced” or “bathed”-cultured, we employed a geometric morphometrics approach. This approach allowed us to compare and analyze the dynamic changes in the carapace morphology of both the original and “introduced” crabs in Yangcheng Lake and high-standard ponds in Kunshan City at 0, 7, 14, and 30 days after “bathing” culture. The geometric morphological analysis of the carapace was conducted using a system of 35 established landmarks. The stepwise discriminant analysis of the relative distortion score revealed morphological differences between “introduced” and resident original crabs in the Yangcheng Lake area and in high-standard modified ponds after 7, 14, and 30 days of bathing culture. The accuracy of the discriminant analysis was 100%. The results of the geometric morphological visualization demonstrated that the carapaces of the bathed crabs underwent adaptive changes in the water. However, even after one month of bathing culture, the “introduced” crabs in lakes and ponds could not reach the morphological characteristics of the original crabs, i.e., their carapaces did not exhibit the characteristics of the original crabs.
{"title":"Identification of “Bathed” Chinese Mitten Crabs (Eriocheir sinensis) Using Geometric Morphological Analysis of the Carapace","authors":"Yiqian Xu, Junren Xue, Hongbo Liu, T. Jiang, Xiubao Chen, Jian Yang","doi":"10.3390/fishes9010006","DOIUrl":"https://doi.org/10.3390/fishes9010006","url":null,"abstract":"To confirm whether Chinese mitten crabs (Eriocheir sinensis), commonly known as hairy crabs or river crabs, in non-Yangcheng Lake areas undergo morphological convergence with the original crabs in the Yangcheng Lake purse seine and high-standard modified aquaculture ponds after being “introduced” or “bathed”-cultured, we employed a geometric morphometrics approach. This approach allowed us to compare and analyze the dynamic changes in the carapace morphology of both the original and “introduced” crabs in Yangcheng Lake and high-standard ponds in Kunshan City at 0, 7, 14, and 30 days after “bathing” culture. The geometric morphological analysis of the carapace was conducted using a system of 35 established landmarks. The stepwise discriminant analysis of the relative distortion score revealed morphological differences between “introduced” and resident original crabs in the Yangcheng Lake area and in high-standard modified ponds after 7, 14, and 30 days of bathing culture. The accuracy of the discriminant analysis was 100%. The results of the geometric morphological visualization demonstrated that the carapaces of the bathed crabs underwent adaptive changes in the water. However, even after one month of bathing culture, the “introduced” crabs in lakes and ponds could not reach the morphological characteristics of the original crabs, i.e., their carapaces did not exhibit the characteristics of the original crabs.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138950447","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}
A. Sánchez‐Paz, T. Encinas-García, F. Mendoza-Cano
In this study, the primers of different protocols for the detection of White Spot Syndrome Virus (WSSV) were analyzed in silico to evaluate their potential performance in PCR. As with any biological entity, this virus evolves constantly. Thus, this analysis showed that a few primers, including those recommended by the World Organization for Animal Health (WOAH), might mismatch with some isolates of WSSV, specially with isolates more recently sequenced. Furthermore, a set of primers recommended by WOAH, showed the potential to self-dimer and form hairpin loop structures, which could affect the efficiency of PCR, resulting in an inaccurate diagnostic result. From our perspective, and considering the evolutionary trajectory of this virus, it may be time for the WOAH to update the PCR protocols recommended for WSSV detection, which remains as a highly prevalent and lethal virus.
{"title":"In Silico Evaluation of the PCR Performance of Different Tests for Detection of WSSV","authors":"A. Sánchez‐Paz, T. Encinas-García, F. Mendoza-Cano","doi":"10.3390/fishes9010005","DOIUrl":"https://doi.org/10.3390/fishes9010005","url":null,"abstract":"In this study, the primers of different protocols for the detection of White Spot Syndrome Virus (WSSV) were analyzed in silico to evaluate their potential performance in PCR. As with any biological entity, this virus evolves constantly. Thus, this analysis showed that a few primers, including those recommended by the World Organization for Animal Health (WOAH), might mismatch with some isolates of WSSV, specially with isolates more recently sequenced. Furthermore, a set of primers recommended by WOAH, showed the potential to self-dimer and form hairpin loop structures, which could affect the efficiency of PCR, resulting in an inaccurate diagnostic result. From our perspective, and considering the evolutionary trajectory of this virus, it may be time for the WOAH to update the PCR protocols recommended for WSSV detection, which remains as a highly prevalent and lethal virus.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138954696","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}
D. Valić, Matej Kristan Mirković, V. Besendorfer, E. Teskeredžić
Conservation of indigenous species, especially endemic ones, is of the utmost importance. Morphological determination of species is usually not sufficient; therefore, molecular phylogenetic analyses of the Illyrian chub, Squalius illyricus, and the Zrmanja chub, Squalius zrmanjae, from the Krka River were performed. For the genetic characterization of the mitochondrial gene cytochrome b and the non-coding nuclear region Cyfun P, 15 specimens from each species were subjected to analysis. The obtained sequences were aligned with similar ones from GenBank to determine the taxonomic and phylogenetic position of these species. The obtained molecular results imply that S. zrmanjae from the Krka River has a nuclear region that resembles Dalmatian rudd, Scardinius dergle. This result implies an introgression event and the transfer of genetic information between the two genera. The investigated species are on the IUCN Red List of Threatened Species, their biological data are scarce, and further investigation and protection are needed.
保护本土物种,尤其是特有物种至关重要。通常,仅从形态上确定物种是不够的;因此,我们对克尔卡河中的伊利里亚鲢鱼(Squalius illyricus)和兹尔曼亚鲢鱼(Squalius zrmanjae)进行了分子系统学分析。为了确定线粒体基因细胞色素 b 和非编码核区 Cyfun P 的遗传特征,对每个物种的 15 个标本进行了分析。获得的序列与 GenBank 中的相似序列进行了比对,以确定这些物种的分类和系统发育位置。获得的分子结果表明,克尔卡河的 S. zrmanjae 的核区与达尔马提亚白鲑(Scardinius dergle)相似。这一结果意味着这两个种属之间存在引种事件和遗传信息的转移。所调查的物种已被列入《世界自然保护联盟濒危物种红色名录》,其生物数据稀缺,需要进一步调查和保护。
{"title":"Molecular Analysis of Two Endemic Squalius Species: Evidence for Intergeneric Introgression among Cyprinids and Conservation Issues","authors":"D. Valić, Matej Kristan Mirković, V. Besendorfer, E. Teskeredžić","doi":"10.3390/fishes9010004","DOIUrl":"https://doi.org/10.3390/fishes9010004","url":null,"abstract":"Conservation of indigenous species, especially endemic ones, is of the utmost importance. Morphological determination of species is usually not sufficient; therefore, molecular phylogenetic analyses of the Illyrian chub, Squalius illyricus, and the Zrmanja chub, Squalius zrmanjae, from the Krka River were performed. For the genetic characterization of the mitochondrial gene cytochrome b and the non-coding nuclear region Cyfun P, 15 specimens from each species were subjected to analysis. The obtained sequences were aligned with similar ones from GenBank to determine the taxonomic and phylogenetic position of these species. The obtained molecular results imply that S. zrmanjae from the Krka River has a nuclear region that resembles Dalmatian rudd, Scardinius dergle. This result implies an introgression event and the transfer of genetic information between the two genera. The investigated species are on the IUCN Red List of Threatened Species, their biological data are scarce, and further investigation and protection are needed.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138958561","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}
In group-living species, social interactions with conspecifics play a crucial role in group formation and the ability to make consensus decisions, with far-reaching consequences for ecological and evolutionary processes in natural populations. Individual recognition and partner preferences based on social familiarity are important mechanisms driving a range of interactions between individual fish and social structure in fish populations. However, the social interactions of gregarious species are also influenced by the ecological environment experienced by individuals. This study aimed to determine how fish shoals’ structure is shaped by increased turbidity, a typical environmental constraint in anthropogenically impacted rivers. A freshwater, shoal-forming, visually orientated pelagic fish—bleak (Alburnus alburnus)—was used as the model organism. The behavior of 40 individuals at three different turbidity levels (0 NTU, 30 NTU, 60 NTU) was tested in the laboratory experiment. Specifically, the aim was to determine if the turbidity reduces between individual distances in response to the deteriorated visual conditions. The results showed that bleaks increased the compactness of the shoal even at the medium turbidity level (30 NTU), and compactness further increased with turbidity. Such results indicate that turbidity is an important phenomenon influencing the structure of shoals and ultimately an ecological process in natural fish populations in ecosystems affected by increasing turbidity.
{"title":"The Effect of Turbidity on the Behavior of Bleak (Alburnus alburnus)","authors":"P. Horká, Monika Vlachova","doi":"10.3390/fishes9010003","DOIUrl":"https://doi.org/10.3390/fishes9010003","url":null,"abstract":"In group-living species, social interactions with conspecifics play a crucial role in group formation and the ability to make consensus decisions, with far-reaching consequences for ecological and evolutionary processes in natural populations. Individual recognition and partner preferences based on social familiarity are important mechanisms driving a range of interactions between individual fish and social structure in fish populations. However, the social interactions of gregarious species are also influenced by the ecological environment experienced by individuals. This study aimed to determine how fish shoals’ structure is shaped by increased turbidity, a typical environmental constraint in anthropogenically impacted rivers. A freshwater, shoal-forming, visually orientated pelagic fish—bleak (Alburnus alburnus)—was used as the model organism. The behavior of 40 individuals at three different turbidity levels (0 NTU, 30 NTU, 60 NTU) was tested in the laboratory experiment. Specifically, the aim was to determine if the turbidity reduces between individual distances in response to the deteriorated visual conditions. The results showed that bleaks increased the compactness of the shoal even at the medium turbidity level (30 NTU), and compactness further increased with turbidity. Such results indicate that turbidity is an important phenomenon influencing the structure of shoals and ultimately an ecological process in natural fish populations in ecosystems affected by increasing turbidity.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138954678","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}
Zheng-Ting Jiang, Gang Shi, Dongneng Jiang, Yu Li, Yuang-Qing Huang, Hong-Juan Shi, Guang-Li Li
The spotted scat (Scatophagus argus) is an important ornamental species with sexually biased ornamental values that favor males. Therefore, it makes sense to breed mono-male fingerlings as ornamental fish. The spotted scat has an XX/XY sex determination system; therefore, the first step in producing genetically all-male offspring should be the induction of a fertile sex-reversed XY pseudo-female, which would then be mated with a normal XY male to produce a YY super-male. However, the XY pseudo-female produced by estradiol (E2) treatment failed due to ovarian malformations. Here, male to female sex reversal was induced in spotted scat through a combination of E2 and an androgen inhibitor (trilostane, TR). Spotted scat fingerlings of approximately 2.8–3.5 cm were fed a diet containing both E2 (300 µg/g) and TR (300 µg/g). The fish were treated for 90 days and then fed a normal diet until they reached one year of age, when they were sampled. Twenty-eight treated XY individuals were identified using sex-linked markers. According to their gonadal histological characteristics, these treated XY fish could be divided into three groups: males with testes (n = 21), intersex individuals with ovaries–testes (n = 3), and fully sex-reversed individuals with ovaries (n = 4). All treated XX fish (n = 8) developed into normal females. There were no obvious abnormalities in the ovaries of the XY sex-reversed fish compared to the treated XX fish. Serum 11-ketotestosterone (11-KT) levels were significantly lower in XY-reversed females and treated XX females than in XY males. Compared with XY male fish, the expression of female (42sp50, foxl2, figla, zar1, and zp2) and male (dmrt1, gsdf, amh and cyp11b2) biased genes was up- and down-regulated, respectively, in the gonads of XY-completely sex-reversed fish. Immunohistochemical results indicate that 42Sp50 was expressed in oocytes of XY-partially and completely sex-reversed fish, while strong Gsdf signals were mainly detectable in testicular somatic cells of XY-partially sex-reversed fish and XY male fish. XY females were successfully produced by the combined treatment of E2 and TR in the spotted scat. Their fertility will be tested in the future.
{"title":"Preliminary Trial of Male to Female Sex Reversal by 17β-Estradiol in Combination with Trilostane in Spotted Scat (Scatophagus argus)","authors":"Zheng-Ting Jiang, Gang Shi, Dongneng Jiang, Yu Li, Yuang-Qing Huang, Hong-Juan Shi, Guang-Li Li","doi":"10.3390/fishes9010001","DOIUrl":"https://doi.org/10.3390/fishes9010001","url":null,"abstract":"The spotted scat (Scatophagus argus) is an important ornamental species with sexually biased ornamental values that favor males. Therefore, it makes sense to breed mono-male fingerlings as ornamental fish. The spotted scat has an XX/XY sex determination system; therefore, the first step in producing genetically all-male offspring should be the induction of a fertile sex-reversed XY pseudo-female, which would then be mated with a normal XY male to produce a YY super-male. However, the XY pseudo-female produced by estradiol (E2) treatment failed due to ovarian malformations. Here, male to female sex reversal was induced in spotted scat through a combination of E2 and an androgen inhibitor (trilostane, TR). Spotted scat fingerlings of approximately 2.8–3.5 cm were fed a diet containing both E2 (300 µg/g) and TR (300 µg/g). The fish were treated for 90 days and then fed a normal diet until they reached one year of age, when they were sampled. Twenty-eight treated XY individuals were identified using sex-linked markers. According to their gonadal histological characteristics, these treated XY fish could be divided into three groups: males with testes (n = 21), intersex individuals with ovaries–testes (n = 3), and fully sex-reversed individuals with ovaries (n = 4). All treated XX fish (n = 8) developed into normal females. There were no obvious abnormalities in the ovaries of the XY sex-reversed fish compared to the treated XX fish. Serum 11-ketotestosterone (11-KT) levels were significantly lower in XY-reversed females and treated XX females than in XY males. Compared with XY male fish, the expression of female (42sp50, foxl2, figla, zar1, and zp2) and male (dmrt1, gsdf, amh and cyp11b2) biased genes was up- and down-regulated, respectively, in the gonads of XY-completely sex-reversed fish. Immunohistochemical results indicate that 42Sp50 was expressed in oocytes of XY-partially and completely sex-reversed fish, while strong Gsdf signals were mainly detectable in testicular somatic cells of XY-partially sex-reversed fish and XY male fish. XY females were successfully produced by the combined treatment of E2 and TR in the spotted scat. Their fertility will be tested in the future.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138961157","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}
Yudi Herdiana, B. Wiryawan, S. H. Wisudo, J. Tweedley, I. Yulianto, H. Retnoningtyas, Neil Randell Loneragan
Small-scale tropical fisheries are complex systems that utilize multiple fishing gears to target various species. In this study, we investigated small-scale reef and demersal fisheries in Saleh Bay, Indonesia, using catch and effort data from 2016 to 2019, where 57.7 percent of the catch was grouper (serranids) and snapper (lutjanids). Despite the complexity (75 documented species and eight fishing methods), this fishery is characterized by the catches of four dominant species: leopard coral grouper (Plectropomus leopardus), orange-spotted-grouper (Epinephelus coioides), spotted coral grouper (P. maculatus), and malabar blood snapper (Lutjanus malabaricus). The species caught varied among fishing methods. Over 90% of the catch was attributed to three primary fishing methods: bottom longline, speargun, and handline. Multivariate analyses found that fishing depth, season, and/or year significantly influenced the catch composition for each of these fishing methods. Fishing activities exhibit a temporal pattern influenced by monsoonal seasons. Results also suggest that fishers employ specialized fishing tactics by targeting high-value species to maximize their profits. This study recommends a management strategy of focusing on monitoring and managing the three main fishing gears and four important species during their peak seasons to reduce some of the complexity and management costs.
{"title":"Untangling the Complexity of Small-Scale Fisheries: Building an Understanding of Grouper-Snapper Fisheries Dynamics in Saleh Bay, West Nusa Tenggara, Indonesia","authors":"Yudi Herdiana, B. Wiryawan, S. H. Wisudo, J. Tweedley, I. Yulianto, H. Retnoningtyas, Neil Randell Loneragan","doi":"10.3390/fishes9010002","DOIUrl":"https://doi.org/10.3390/fishes9010002","url":null,"abstract":"Small-scale tropical fisheries are complex systems that utilize multiple fishing gears to target various species. In this study, we investigated small-scale reef and demersal fisheries in Saleh Bay, Indonesia, using catch and effort data from 2016 to 2019, where 57.7 percent of the catch was grouper (serranids) and snapper (lutjanids). Despite the complexity (75 documented species and eight fishing methods), this fishery is characterized by the catches of four dominant species: leopard coral grouper (Plectropomus leopardus), orange-spotted-grouper (Epinephelus coioides), spotted coral grouper (P. maculatus), and malabar blood snapper (Lutjanus malabaricus). The species caught varied among fishing methods. Over 90% of the catch was attributed to three primary fishing methods: bottom longline, speargun, and handline. Multivariate analyses found that fishing depth, season, and/or year significantly influenced the catch composition for each of these fishing methods. Fishing activities exhibit a temporal pattern influenced by monsoonal seasons. Results also suggest that fishers employ specialized fishing tactics by targeting high-value species to maximize their profits. This study recommends a management strategy of focusing on monitoring and managing the three main fishing gears and four important species during their peak seasons to reduce some of the complexity and management costs.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138960718","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}
Adam T. Piper, Paula J. Rosewarne, Charlotte Pike, Rosalind M. Wright
Optimising the design of passage facilities to restore fluvial connectivity for juvenile European eel (Anguilla anguilla) is a key priority within conservation efforts for the species, across the majority of its freshwater range. Employing an experimental setup that simulated gravity-fed upstream eel passes, this study demonstrated that novel V-profile passes, which incorporate two lateral slopes (15°), performed better than laterally flat passes over the flow rates tested (0.2–0.6 L s−1). For the small eel size used (60–80 mm length), the bristle substrate consistently outperformed studs, but the lateral slope had a greater effect on passage metrics than the substrate choice. Our findings strongly support the use of V-shaped channels for upstream migrating eel at fish passage facilities, particularly in scenarios where flow rates may be elevated and/or fluctuating, such as for gravity-fed passes.
优化通道设施的设计以恢复欧洲鳗鲡幼鱼的河道连通性,是欧洲鳗鲡这一物种在其大部分淡水区域保护工作的重中之重。本研究采用实验装置模拟重力作用下的上游鳗鱼通道,结果表明,在测试的流速(0.2-0.6 升/秒)范围内,包含两个横向斜坡(15°)的新型 V 型鳗鱼通道比横向扁平通道的性能更好。对于使用的小规格鳗鱼(体长 60-80 毫米),鬃毛基质的性能始终优于螺柱,但横向坡度对通过指标的影响大于基质选择。我们的研究结果有力地支持了在鱼类通道设施中为鳗鱼的上游洄游使用 V 形通道,特别是在流速可能会升高和/或波动的情况下,例如重力式通道。
{"title":"The Eel Ascending: The Influence of Lateral Slope, Climbing Substrate and Flow Rate on Eel Pass Performance","authors":"Adam T. Piper, Paula J. Rosewarne, Charlotte Pike, Rosalind M. Wright","doi":"10.3390/fishes8120612","DOIUrl":"https://doi.org/10.3390/fishes8120612","url":null,"abstract":"Optimising the design of passage facilities to restore fluvial connectivity for juvenile European eel (Anguilla anguilla) is a key priority within conservation efforts for the species, across the majority of its freshwater range. Employing an experimental setup that simulated gravity-fed upstream eel passes, this study demonstrated that novel V-profile passes, which incorporate two lateral slopes (15°), performed better than laterally flat passes over the flow rates tested (0.2–0.6 L s−1). For the small eel size used (60–80 mm length), the bristle substrate consistently outperformed studs, but the lateral slope had a greater effect on passage metrics than the substrate choice. Our findings strongly support the use of V-shaped channels for upstream migrating eel at fish passage facilities, particularly in scenarios where flow rates may be elevated and/or fluctuating, such as for gravity-fed passes.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138994956","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}
Grouper aquaculture is a rapidly growing and dynamic industry within the Taiwan aquaculture sector that serves as an important source of income generation. Farming fishes at a better location (FFABL) is a promising production strategy. This study evaluated the production and economic performance of grouper farming in Taiwan. This investigation employed two steps: (1) a cost–benefit analysis to determine the main component affecting profitability; and (2) multivariate statistics to clarify the relationship between biological and economic factors. The findings suggest that the best choice of species is hybrid giant grouper that generates and highlights a positive income, viable benefit–cost ratio and profit rate. The study found the feed management of hybrid giant groupers requires more consideration due to its low feed conversion ratio. The producers need to replace trash fish in commercial feed during the production cycle to ensure better feed management. Finally, this paper argues that feed is the main constraint for grouper farming, which is sensitive to any change in feed productivity, and this constraint must be solved to sustain the grouper industry in Taiwan.
{"title":"The Bioeconomic Analysis of Hybrid Giant Grouper (Epinephelus fuscoguttatus × Epinephelus lanceolatus) and Green Grouper (Epinephelus malabaricus): A Case Study in Taiwan","authors":"Po-Lin Huang, Farok Afero, Yao Chang, Bo-Ying Chen, Hsun-Yu Lan, Yen-Lung Hou, Cheng-Ting Huang","doi":"10.3390/fishes8120610","DOIUrl":"https://doi.org/10.3390/fishes8120610","url":null,"abstract":"Grouper aquaculture is a rapidly growing and dynamic industry within the Taiwan aquaculture sector that serves as an important source of income generation. Farming fishes at a better location (FFABL) is a promising production strategy. This study evaluated the production and economic performance of grouper farming in Taiwan. This investigation employed two steps: (1) a cost–benefit analysis to determine the main component affecting profitability; and (2) multivariate statistics to clarify the relationship between biological and economic factors. The findings suggest that the best choice of species is hybrid giant grouper that generates and highlights a positive income, viable benefit–cost ratio and profit rate. The study found the feed management of hybrid giant groupers requires more consideration due to its low feed conversion ratio. The producers need to replace trash fish in commercial feed during the production cycle to ensure better feed management. Finally, this paper argues that feed is the main constraint for grouper farming, which is sensitive to any change in feed productivity, and this constraint must be solved to sustain the grouper industry in Taiwan.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138966186","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}