Journal of fish biology最新文献

{"title":"Novel use of deep neural networks on photographic identification of epaulette sharks (Hemiscyllium ocellatum) across life stages.","authors":"Martina Lonati, Mohammad Jahanbakht, Danielle Atkins, Stacy L Bierwagen, Andrew Chin, Adam Barnett, Jodie L Rummer","doi":"10.1111/jfb.15887","DOIUrl":"https://doi.org/10.1111/jfb.15887","url":null,"abstract":"<p><p>Photographic identification (photo ID) is an established method that is used to count animals and track individuals' movements. This method performs well with some species of elasmobranchs (i.e., sharks, skates, and rays) where individuals have distinctive skin patterns. However, the unique skin patterns used for ID must be stable through time to allow re-identification of individuals in future sampling events. More recently, artificial intelligence (AI) models have substantially decreased the labor-intensive process of matching photos in extensive photo ID libraries and increased the reliability of photo ID. Here, photo ID and AI are used for the first time to identify epaulette sharks (Hemiscyllium ocellatum) at different life stages for approximately 2 years. An AI model was developed to assess and compare the reliability of human-classified ID patterns in juvenile and neonate sharks. The model also tested the persistence of unique patterns in adult sharks. Results indicate that immature life stages are unreliable for pattern identification, using both human and AI approaches, due to the plasticity of these subadult growth forms. Mature sharks maintain their patterns through time and can be identified by AI models with approximately 86% accuracy. The approach outlined in this study has the potential of validating the stability of ID patterns through time; however, testing on wild populations and long-term datasets is needed. This study's novel deep neural network development strategy offers a streamlined and accessible framework for generating a reliable model from a small data set, without requiring high-performance computing. Since many photo ID studies commence with limited datasets and resources, this AI model presents practical solutions to such constraints. Overall, this approach has the potential to address challenges associated with long-term photo ID data sets and the application of AI for shark identification.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141912906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Size-selective harvesting drives genomic shifts in a harvested population.","authors":"Daniel E Sadler, Tiina Sävilammi, Stephan N van Dijk, Phillip C Watts, Silva Uusi-Heikkilä","doi":"10.1111/jfb.15901","DOIUrl":"https://doi.org/10.1111/jfb.15901","url":null,"abstract":"<p><p>Overfishing not only drastically reduces the number of fish in an exploited population but is also often selective for body size by removing the largest individuals from a population. Here, we study experimentally the evolutionary effects of size-selective harvesting using whole-genome sequencing on a model organism, the zebrafish (Danio rerio). We demonstrate genomic shifts in the populations exposed to size-selective harvesting for five generations and show reduced genetic diversity in all harvested lines, including the control line (non-size-selected). We also determine differences in groups of genes related to certain gene ontology annotations between size-selectively harvested lines, with enrichment in nervous system related genes in the large-selected lines. Our results illuminate the biological processes underlying fisheries-induced genetic changes and hence contribute toward the understanding of the changes potentially associated with the vulnerability of an exploited population to future stressors.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141901937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fish habitat ecology in a changing climate","authors":"Eoin J. O'Gorman,&nbsp;Rui P. Vieira,&nbsp;Anna M. Sturrock","doi":"10.1111/jfb.15881","DOIUrl":"10.1111/jfb.15881","url":null,"abstract":"<p>Understanding the factors driving fish behavior, physiology, and survival is increasingly important during this period of unprecedented global change, given their implications for fisheries stability and ecosystem health. Habitat quality and quantity shape fish population dynamics and eco-evolutionary trajectories. Quantifying the habitat needs of fish across all life stages (and of their predators and prey) is challenging, however, and relies on diverse approaches such as field observations, laboratory experiments, genomics, chemical tracers, telemetry, and modeling. Successful integration of these data into management and policy requires open and constructive knowledge exchange between natural and social scientists, stakeholders, managers, and policymakers, and new tools to analyse and visualize these complex datasets. Building this social-ecological connectivity is particularly important in dynamic boundary systems (e.g., estuaries) and for protecting species characterized by trans-boundary movements (e.g., between rivers and seas, or across jurisdictional borders) if we are to maximize the benefits for nature and humans alike.</p><p>Here, we present a collection of papers that deal with these topics in a Special Issue born from the Fisheries Society of the British Isles (FSBI) 2023 Symposium, “Fish Habitat Ecology in a Changing Climate” (see Figure 1), held at the University of Essex and co-convened by the Centre for Environment, Fisheries and Aquaculture Science (Cefas). The overarching theme was inspired by a previous Jack Jones Lecture by Jonathan Rice, “Understanding fish habitat ecology to achieve conservation” (Rice, <span>2005</span>), where he argues that “habitat science can provide the unifying concepts to bring together ecological studies of physiological tolerances, predator avoidance, foraging and feeding, reproduction and life histories.” Here, we broaden that definition to include the downstream effects of habitat (and habitat loss or restoration) on ecosystem services such as human food supply and nutrient requirements, and how humans and habitats interact in the space of fisheries and ecosystem management.</p><p>The papers in this FSBI 2023 Symposium Issue fall under five major themes, which all have clear links to UN Sustainable Development Goals (e.g., Climate Action, Life Below Water), and the critical roles and services that fish provide (see Figure 2). Sustainable management of fish populations first requires an appreciation that they are not static entities and can move between different habitats that could provide key resources or shelter in different seasons or life stages. Quantifying fish movement and connectivity (Theme 1) is thus a key empirical and analytical challenge that needs to be overcome. Fish also do not exist in isolation, so managing a target stock requires understanding of how changes to ecosystems, particularly in their predators or prey, may underpin unexpected declines in the species of interest.","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jfb.15881","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141901935","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}

{"title":"Patterns of persistence: Genetic and behavioral population complexity of winter flounder amid population declines","authors":"Tara E. Dolan,&nbsp;Kevin A. Feldheim,&nbsp;Shannon J. O'Leary,&nbsp;Catherine M. Fede,&nbsp;Anne E. McElroy,&nbsp;Michael G. Frisk","doi":"10.1111/jfb.15890","DOIUrl":"10.1111/jfb.15890","url":null,"abstract":"<p>Winter flounder <i>Pseudopleuronectes americanus</i> (Walbaum 1792) are a coastal flatfish species of economic and cultural importance that have dwindled to &lt;15, % of their historic abundance in the southern New England/Mid-Atlantic region of the United States, with evidence indicating near-extirpation of certain local populations. This species exhibits intricate behaviors in spawning and migration that contribute to population complexity and resilience. These behaviors encompass full or partial philopatry to natal estuaries, the generation of multiple pulses of larval delivery, and partial migration. The patterns of genetic diversity within and among estuaries and cohorts presented here carry important implications in understanding the susceptibility to demographic shocks, even if the full extent of genetic diversity within and among winter flounder stocks on the US East Coast remains unresolved. Our findings reveal connectivity between estuaries in Long Island, New York, suggesting the potential for genetic rescue of depleted subpopulations. Family reconstruction and relatedness analysis indicate that split cohorts and migration contingents are not the result of genetically distinct lineages. We found no evidence for genetic structure separating these groups, and in some instances, we were able to detect closely related individuals that belonged to different migratory contingents or cohorts. Characterizing the spatial and behavioral organization of this species at the population level is crucial for comprehending its potential for recovery, not only in terms of biomass but also in reinstating the complex population structure that supports resilience. The search for generality in winter flounder spawning and migration behavior remains elusive, but perhaps the lack of generalities within this species is what has allowed it to persist in the face of decades of environmental and anthropogenic stressors.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141897610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New report of the rare Sciadonus alphacrucis Melo et al., 2022 (Teleostei, Ophidiiformes, Bythitidae), DNA barcoding, and range extension in the western South Atlantic","authors":"Marcos Roberto dos Reis Júnior,&nbsp;Heloisa De Cia Caixeta,&nbsp;Claudio Oliveira,&nbsp;Marcelo Roberto Souto de Melo","doi":"10.1111/jfb.15896","DOIUrl":"10.1111/jfb.15896","url":null,"abstract":"<p><i>Sciadonus alphacrucis</i> Melo, Gomes, Møller &amp; Nielsen, 2022 is a rare deep-sea species, previously known from only two specimens collected off São Paulo State, southeastern Brazil, in the western South Atlantic. Herein, we report a new specimen of <i>S. alphacrucis</i> collected on the continental slope off Santa Catarina State, southern Brazil, thereby extending its known distribution by 420 km. Additionally, we provide the new meristic and morphometric data, the molecular identification using sequences of the cytochrome c oxidase subunit I (<i>COI</i>), an updated distribution map, and a discussion of troglomorphic traits.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141897609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reproductive morphophysiology of an iteroparous batch spawner fish: from early follicle development to ovulation","authors":"Omar Domínguez-Castanedo,&nbsp;Cyndi G. Hernandez-Coronado,&nbsp;David A. Martínez-Espinosa,&nbsp;Ana María Rosales-Torres","doi":"10.1111/jfb.15891","DOIUrl":"10.1111/jfb.15891","url":null,"abstract":"<p>Batch spawner fishes develop successive clutches of oocytes which allows them to participate in many reproductive cycles during their adult life (iteroparous) and spawn in multiple events within each breeding cycle. Here, ovarian follicular development was morpho-functionally analyzed in females of the iteroparous batch spawner fish <i>Gymnocorymbus ternetzi</i>. To obtain better insights into the reproductive morpho-physiology in batch spawners, the objective of this research was to analyze the dynamics of the follicular development, with its hormonal regulation between two active reproduction events. We found that over 16 days, follicles progressed asynchronously to chromatin nucleolus, Primary and Secondary growth stages of oogenesis with progressive secretion of 17β-estradiol (E₂). During the end of secondary growth, the increase in 17α,20β-dihydroxy-4-pregnen-3-one (17,20β-p) was measured relative to the maturation process of the ovarian follicles (e.g., nuclear migration and its rupture during the resumption of meiosis). Interestingly, an additional increase in E₂ was observed after fish reproduction, probably related to the recruitment of new batch follicles for secondary growth. We also measured the high values of multiple condition factor post-reproduction measurements, reflecting more energy invested during the pre-reproductive process. We also quantified high concentrations of 17,20β-p, probably related to the recruitment of a new batch of oogonia to meiosis, presumably secreted by post-ovulatory follicles, after fish reproduction. We finally found that fish without exposure to reproductive stimulus developed a regression phase at day 24, characterized by massive follicle atresia, that allow them to recycle energy and constitutive materials of the follicles invested during oogenesis for another reproductive cycle.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141901936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Barramundi (Lates calcarifer) rare coloration patterns: a multiomics approach to understand the “panda” phenotype","authors":"Roberta Marcoli,&nbsp;David B. Jones,&nbsp;Cecile Massault,&nbsp;Paul J. Harrison,&nbsp;Holly S. Cate,&nbsp;Dean R. Jerry","doi":"10.1111/jfb.15892","DOIUrl":"10.1111/jfb.15892","url":null,"abstract":"<p>The barramundi (<i>Lates calcarifer</i>), a significant aquaculture species, typically displays silver to bronze coloration. However, attention is now drawn to rare variants like the “panda” phenotype, characterized by blotch-like patterns of black (PB) and golden (PG) patches. This phenotype presents an opportunity to explore the molecular mechanisms underlying color variations in teleosts. Unlike stable color patterns in many fish, the “panda” variant demonstrates phenotypic plasticity, responding dynamically to unknown cues. We propose a complex interplay of genetic factors and epigenetic modifications, focusing on DNA methylation. Through a multiomics approach, we analyze transcriptomic and methylation patterns between PB and PG patches. Our study reveals differential gene expression related to melanosome trafficking and chromatophore differentiation. Although the specific gene responsible for the PB–PG difference remains elusive, candidate genes like <i>asip1</i>, <i>asip2</i>, <i>mlph</i>, and <i>mreg</i> have been identified. Methylation emerges as a potential contributor to the “panda” phenotype, with changes in gene promoters like <i>hand2</i> and <i>dynamin</i> possibly influencing coloration. This research lays the groundwork for further exploration into rare barramundi color patterns, enhancing our understanding of color diversity in teleosts. Additionally, it underscores the “panda” phenotype's potential as a model for studying adult skin coloration.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jfb.15892","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141875018","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}

{"title":"Errors in estimating reproductive parameters with macroscopic methods: a case study on the protogynous blacktip grouper Epinephelus fasciatus (Forsskål 1775)","authors":"Ken Longenecker,&nbsp;Ross Langston,&nbsp;Juliaeta Mamesah,&nbsp;Yuliana Natan,&nbsp;Maureen Pattinasarany,&nbsp;Abdul W. Radjab,&nbsp;Ahmad Romdon,&nbsp;Fismatman Ruli,&nbsp;Prandito Simanjuntak,&nbsp;Febby L. Sinaga,&nbsp;Gino V. Limmon,&nbsp;Erik C. Franklin","doi":"10.1111/jfb.15893","DOIUrl":"10.1111/jfb.15893","url":null,"abstract":"<p>A size-based, histological analysis of the reproductive life history of the blacktip grouper, <i>Epinephelus fasciatus</i> (Forsskål 1775), was conducted in Indonesia to evaluate the error rate associated with macroscopic reproductive analysis. Histological results indicated that <i>E. fasciatus</i> was protogynous with female <i>L</i>₅₀ at 13.4 cm total length (L_T) and a size at sexual transition of 22.0 cm L_T. The weight–length relationship for the species was <i>W</i> = 0.011 <i>L</i>^3.13. Overall sex ratios were significantly female biased, operational sex ratios were significantly male biased, and sex ratios of mature individuals varied predictably with length from female to male dominance as size increased. No significant relationship between length and batch fecundity was found. The population has a spawning period from February to August. Overall, 54.4% of macroscopic evaluations were incorrect compared to histological results. Of the errors, 14.8% were a failure to detect ovotestes, 12.7% were classifying non-gonadal tissue as ovary or testis, 12.2% were misclassifying sex, and 12.7% were misclassifying maturity status. However, the largest source of error (47.7%) was from misclassifying both sex and maturity status. Of these, 92.9% were macroscopically classified as immature females, but were histologically confirmed to be mature males. Compared to histological results, the only accurate macroscopic results were the absence of a sex-based difference in weight–length relationship and spawning seasonality estimated by a gonadosomatic index (February–June). The use of macroscopic methods to estimate reproductive life-history parameters for sex-changing reefes fish may introduce significant inaccuracies and misinterpretations. Of the parameters estimated by histological methods, size at maturity, size-specific sex ratios, and spawning seasonality have the greatest potential to inform local fishery management policy.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141860012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Schistura sonarengaensis, a new species of cave-dwelling loach (Teleostei: Nemacheilidae) from Meghalaya, northeast India","authors":"Dran Khlur B. Mukhim,&nbsp;Kangkan Sarma,&nbsp;Hrishikesh Choudhury,&nbsp;Rejani Chandran,&nbsp;Rajdeep Das,&nbsp;Rajeev K. Singh,&nbsp;Deisakee P. Warbah,&nbsp;Uttam Kumar Sarkar,&nbsp;Dandadhar Sarma","doi":"10.1111/jfb.15856","DOIUrl":"10.1111/jfb.15856","url":null,"abstract":"<p>A new species of nemacheilid loach, <i>Schistura sonarengaensis</i> sp. nov., is described from three cave-dwelling populations (Barak–Surma–Meghna drainage) in the South Garo Hills district of Meghalaya, India. The new species possesses prominent eyes but is easily distinguished from all the congeners of the genus <i>Schistura</i> from Barak–Surma–Meghna and adjacent rivers drainages of northeast Indian (except <i>S. syngkai</i>) in having 13–26 vertically elongated to circular mid-lateral black blotches (brownish in life) overlayered on a grayish-black mid-lateral stripe on a dull white or pale-beige (golden brown in life) body. However, it can be easily distinguished from <i>S. syngkai</i> in having a complete (vs. incomplete) lateral line with more 72–89 (vs. 19–42) lateral-line pored scales, greater pre-dorsal length (48.5–53.1 vs. 41.9–44.1 %SL), a wider body at dorsal-fin origin (11.3–16.7 vs. 9.4–10.3 %SL), greater dorsal (18.1–21.1 vs. 15.1–17.0 %SL) and lateral (20.9–24.1 vs. 17.4–18.9 %SL) head length, a wider head (14.5–18.5 vs. 11.6–13.3 %SL), and moderately forked (vs. emarginated) caudal fin. Further, molecular analysis confirms the distinctiveness of <i>S</i>. <i>sonarengaensis</i> sp. nov. from its congeners found in northeast India by significant divergences with uncorrected genetic distance ranging from 3.7% to 17.3% in the mitochondrial cytochrome <i>c</i> oxidase subunit I (COI) gene dataset. The phylogenetic position of the new species with its sister species was evaluated using maximum likelihood and Bayesian analysis. The species delimitation approaches assemble species by automatic partitioning (ASAP) and Poisson tree processes (PTP) utilized for testing species assignments consistently identified our test group as a distinct species from its sister species. Although the new species lacks typical morphological adaptations usually associated with a subterranean life, such as complete absence (or vestigial presence) of eyes and pigmentation, it exhibits a reduction of pigmentation when compared to the epigean congeners.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141855654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ex-post evaluation of fishery management policies on wild fisheries production in northern Cabo Verde: An example of mackerel scad (Decapterus macarellus, Carangidae)","authors":"Katelene da Cruz Delgado,&nbsp;Isimemen Osemwegie,&nbsp;Anibal Delgado Medina,&nbsp;Alciany Nascimento da Luz,&nbsp;Zaneta Kubik,&nbsp;Essetchi Paul Kouamelan","doi":"10.1111/jfb.15861","DOIUrl":"10.1111/jfb.15861","url":null,"abstract":"<p>Government policies for marine fisheries have been implemented in Cabo Verde since its independence in 1975, with the aim to prevent overexploitation of wild fish species and promote sustainable fishing practices. Nonetheless, only minor amendments have been made to the legal harvesting size, considering biological sciences. This study, therefore, adopted a transdisciplinary approach to assess the political, ecological, and social dimensions of current fishery policy interventions applicable to the commercially valuable pelagic species <i>Decapterus macarellus</i> (mackerel scad). An ex-post analysis of relevant fishery management policies targeting <i>D. macarellus</i> was conducted. This was supplemented by strengths, weaknesses, opportunities, and threats (SWOT) analysis conducted by key fisheries stakeholders. Stocks assessment was conducted on catch data before (2003–2007) and after (2017–2021) the policy interventions. This was followed by a survey of 175 fishery sector actors to understand their perception of the policies, compliance challenges, and recommendations for reforms. Results showed that although the mackerel scad landing size comparably increased, landing catches were on the decline. Most fisheries stakeholders are aware of the policies implemented and acknowledge their favorable developmental outcomes. However, certain gaps exist in the national marine fisheries policies. For example, there is an absence of follow-up research on implemented fishing policies and a lack of monitoring data on the ecology and distribution of the mackerel scad, which hinders our understanding of the exact causes of the reported continual decrease in catches. There is, therefore, a need for regular monitoring of the environmental health of coastal and marine habitats to inform prioritization and/or reformulation of policy intervention measures to achieve intended conservation outcomes.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jfb.15861","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141855652","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}