Fisheries Research最新文献

{"title":"Effects of headline height on catches in southeastern Australian fish trawls","authors":"Matt K. Broadhurst ,&nbsp;Russell B. Millar","doi":"10.1016/j.fishres.2024.107219","DOIUrl":"10.1016/j.fishres.2024.107219","url":null,"abstract":"<div><div>Benthic fish trawls are used off southeastern Australia to target multiple species that have similar sizes and morphologies to non-target species. These characteristics mean there are limited options for improving selectivity via changes to meshes and/or bycatch reduction devices in the codend. Consequently, simple modifications to the anterior trawl body that potentially exploit behavioural differences to separate species before entry have been prioritised for testing. Optimising trawl headline height is recognized as important for refining selectivity, but causal effects can be difficult to isolate owing to variability among confounding operational or technical factors (such as variable spread ratios, ground gears, and/or towing speeds). Here we attempted to isolate the effects of headline height by alternately fishing a conventional trawl (mean headline height ± SE of 3.76 ± 0.07 m) with a design that was identical in key aspects, but had a ∼22 % reduction in fishing circumference at the mouth and therefore a similar lower average headline height (2.75 ± 0.07 m) across homogenous operational variables. There were no significant differences in the numbers and weights of retained and discarded species between the two trawls, although mean catches of the primary target, tiger flathead, <em>Platycephaus richardsoni</em> were ∼25 % lower in the low trawl, implying this species orientates across the range of conventionally fished heights. Regardless of the trawl, there was a significant, negative main effect of headline height on the weights of total discards and two abundant batoids (smooth stingray, <em>Bathytoshia brevicaudata</em> and greenback stingaree, <em>Urolophus viridis</em>) attributed to lower ground-gear contact pressure and/or an increased footrope height of both trawls, facilitating the escape of some individuals under the trawl. The only other species affected by headline height was velvet leatherjacket <em>Meuschenia scaber</em>, with catches increasing as headline increased; possibly owing to changes in netting panel angles at the trawl mouth that precluded escape. It should be possible to marginally reduce the circumference at the mouth of regional trawls and so reduce headline height and at least some drag while maintaining target catches. More broadly, it appears that regardless of the trawl-body circumference, headline height can indirectly affect species selectivity via concomitant effects on other gear components.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"281 ","pages":"Article 107219"},"PeriodicalIF":2.2,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142655480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mapping essential juvenile habitats of exploited marine fish: Complementary insights from a scientific survey-based model, fishers’ knowledge and fisheries-dependent data","authors":"Gabriel Lahellec ,&nbsp;Youen Vermard ,&nbsp;Olivier Le Pape","doi":"10.1016/j.fishres.2024.107217","DOIUrl":"10.1016/j.fishres.2024.107217","url":null,"abstract":"<div><div>In the Bay of Biscay (BoB, Northeast Atlantic), a preexisting habitat suitability model (HSM) fitted on ecological scientific trawl survey data with restricted partial coverage revealed the concentration of Young of the Year (YoY) common sole (<em>Solea solea</em>) on restricted coastal and estuarine nurseries. To extend the nursery map of sole in the BoB to zones where survey data are lacking and fit with the sole population and stock management extent, we crossed HSM, fishers’ ecological knowledge (FEK) and fisheries-based (FB) data. FB and FEK data also complemented knowledge on juvenile sole habitat and seasonal migration. Thirteen fishers with potential knowledge about the YoY sole distribution were directly interviewed. Direct interviews included both information about the location of juveniles and YoY distribution mapping. With good consensus among fishers, FEK allowed the identification of four new areas hosting essential juvenile habitat for the common sole, revealed the accuracy of the HSM model outside the spatial coverage of the ecological survey, and provided spatial refinement. The FB observation data confirmed the locations of the essential juvenile habitats given by FEK and the spatial distributions of YoY densities predicted from the scientific data. In addition, FB confirmed the seasonal migration of YoY sole, which was preliminarily hypothesized from a local and short-term survey-based study. Our results emphasized the local accuracy of FEK. These findings also underlined the interest in combining several sources of data and methods to map essential fish habitats outside areas well covered by ecological scientific surveys, on order to inform future spatial management measures.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"281 ","pages":"Article 107217"},"PeriodicalIF":2.2,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"The influence of fishing methods on catch size, catch rate, and size distribution of Octopus cyanea (Gray, 1849) in Zanzibar, Tanzania","authors":"Amini I. Hamad ,&nbsp;Christopher A. Muhando ,&nbsp;Batuli M. Yahya","doi":"10.1016/j.fishres.2024.107213","DOIUrl":"10.1016/j.fishres.2024.107213","url":null,"abstract":"<div><div><em>Octopus cyanea</em> (Gray, 1849) is a benthic and diurnally active species found in tropical and subtropical reefs. It is harvested for commercial and subsistence purposes, but some factors in Zanzibar challenge its catch. This study was conducted to determine variations in <em>O. cyanea</em> catch between on-foot and dive fishing methods in Zanzibar. Information from this study would help in the establishment of management plans, which are still challenging in Zanzibar. The catch size, catch rate, and individual size of octopuses from dive and on-foot fishing were determined. Results revealed that about 54.11 % of all octopuses were caught by on-foot fishing and 45.89 % by dive fishing. However, the average catch size (by weight and length) was lower for on-foot fishing than for dive fishing. Moreover, the catch size and catch rate per fisher were higher for dive fishers than for on-foot fishers. The proportion of octopuses weighing ≥ 1000 g constitutes 49 % and 26 % of the total catch by dive and on-foot fishing, respectively, indicating that dive fishing captures a significantly higher percentage of larger individuals than on-foot fishing. Therefore, the concentrated on-foot fishing in shallow water could affect more recruits and juveniles, while high fishing efforts in deep water by dive fishers could impact more spawners and brooders found in these areas. Given these observations, this study emphasizes the necessity of conducting long-term research to accurately identify the peak breeding, spawning, and recruitment seasons.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"281 ","pages":"Article 107213"},"PeriodicalIF":2.2,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bayesian modeling-based analysis on the shared habitat and species association between four Gobiidae in a marine bay ecosystem","authors":"Duqing Shen ,&nbsp;Jie Yin ,&nbsp;Yunlei Zhang ,&nbsp;Chongliang Zhang ,&nbsp;Binduo Xu ,&nbsp;Yupeng Ji ,&nbsp;Yiping Ren ,&nbsp;Ying Xue","doi":"10.1016/j.fishres.2024.107212","DOIUrl":"10.1016/j.fishres.2024.107212","url":null,"abstract":"<div><div>In recent years, with the decline in marine fishery resources, ecosystem-based fisheries management (EBFM) has emerged as an important paradigm in fisheries management, emphasizing the need for species distribution information. Selecting appropriate habitat models is crucial in species distribution studies. Bayesian models could reduce the reliance of species distribution on the data and are particularly suitable for small datasets in marine surveys. In this study, we constructed three Bayesian models to analyze the spatial distribution and shared suitable habitats of four Gobiidae (<em>Myersina filifer</em>, <em>Chaemrichthys stigmatias</em>, <em>Amblychaeturichthys hexanema</em>, and <em>Amoya pflaumi</em>) in Haizhou Bay, China. The interspecific associations of these species were also evaluated using Pearson correlation coefficient (r). Our analyses found that Bayesian regularized neural network (BRNN) model performed better than the other two Bayesian models, and the four Gobiidae species mainly coexisted in the central and southern coastal areas of Haizhou Bay, prey, sea bottom temperature and sediment were the main correlated factors on the habitat of Gobiidae. Furthermore, although the four species exhibited similar feeding habits, intense interspecific competition might not occur due to their considerable dietary breadth, with species associations reflecting the similarity of habitat preferences. For example, <em>M. filifer</em> and <em>A. hexanema</em> inhabited similar areas in spring, and their species association was also relatively high (0.64). This study will help to enhance our understanding of the habitat preferences and interspecific associations of Gobiidae, and provide a framework of spatial based fisheries management at multispecies level in marine bay ecosystems.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"281 ","pages":"Article 107212"},"PeriodicalIF":2.2,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population structure and feeding habits of Carcinoscorpius rotundicauda in the bay environment, Southern Gulf of Thailand","authors":"Sukree Hajisamae ,&nbsp;Kay Khine Soe ,&nbsp;Sofiyudin Maae ,&nbsp;Saweit Chaymongkol ,&nbsp;Akbar John","doi":"10.1016/j.fishres.2024.107216","DOIUrl":"10.1016/j.fishres.2024.107216","url":null,"abstract":"<div><div>This study presents the first comprehensive assessment of the population structure and feeding habits of <em>Carcinoscorpius rotundicauda</em> in Thailand. Sample collection was conducted using crab gill nets at seven sampling sites characterized by distinct ecosystem attributes in Pattani Bay between February 2019 and March 2020. Our findings indicate the presence of a single Asian horseshoe crab (HSC) species within the bay, with a sex ratio of approximately 1:1 (48.1 % males, 51.9 % females) that did not deviate significantly from parity. Habitat variation within the bay did not influence HSC abundance (P &gt; 0.05) whereas monthly abundance fluctuations were highly significant (P &lt; 0.001), peaking in March and reaching the lowest in September. Positive correlations were observed between HSC abundance and environmental factors including dissolved oxygen, temperature, water pH, water depth, and chlorophyll c concentrations. Linear regression analysis revealed a positive correlation between morphometric characteristics and body weight. However, multiple linear regression analysis indicated a negative relationship between body weight and telson length (TEL) and opisthosoma width (OW) of males, as well as TEL of females. The size at which 50 % of the HSC population reached maturity (L₅₀) was estimated to be 12.2 cm for males and 13.5 cm for females based on prosomal width (PW). The average PW measurements of HSC at different egg stages (1–4) from developing to mature females was 14.4 cm, with corresponding body weights ranging from 224 to 243 g. Females at egg of stages 3 and 4 were found throughout the year, indicating multiple spawning events, particularly prevalent in January-April, and predominantly abundant at stations 1, 2, 5 and 6. HSC primarily consumed bivalves (22.1±21.2 %), followed by fishes (5.9±13.0 %) and crustaceans (2.9±9.0 %) by volumetric contribution (%V). This comprehensive study provides novel insights into the population dynamics and feeding ecology of HSC within Thailand. The findings establish a foundational framework for future research endeavors and offer critical data to inform the management and conservation of their habitats.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"281 ","pages":"Article 107216"},"PeriodicalIF":2.2,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using fatty acids and stable isotope analyses to elucidate ontogenetic variations in diet of painted notothen Lepidonotothen larseni during winter at the South Georgia shelf, Antarctic","authors":"Zhi Cao ,&nbsp;Guoping Zhu","doi":"10.1016/j.fishres.2024.107218","DOIUrl":"10.1016/j.fishres.2024.107218","url":null,"abstract":"<div><div>Fish belonging to the Nototheniidae family are considered to be the most significant members of the Notothenioids family and are essential to the Antarctic marine ecology. However, the trophic dynamics of some unexploited species, including semi-pelagic painted notothen <em>Lepidonotothen larseni</em>, remains unknown. This study used fatty acids (FAs) and stable isotope indicators to examine the shift in diet from early juvenile to adult stages at South Georgia throughout winter in order to improve our understanding of the dietary diversity and trophic niche of <em>L. larseni</em>. Thirty different types of fatty acids were found in the muscular tissues of early juveniles (4.10–4.85 cm) and adults (8.7–14.9 cm), yet there was a notable variation in the composition of FAs between the two groups. FAs including C22:6n3, C22:2n6, C16:1n7, and C20:5n3 were found in high amounts in both early juveniles and adults. Both the δ¹⁵N and δ¹³C values of adults were significantly higher than those of early juveniles, suggesting an ontogenetic shift in <em>L. larseni</em>'s diet and trophic niche separation between the two stages of development. Significant separation in marker FAs was also observed between early juveniles and adults. Early juvenile <em>L. larseni</em> primarily fed on pelagic algae or copepods, whereas adults predominantly fed on Antarctic krill (<em>Euphausia superba</em>) on the seafloor and in the water column.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"281 ","pages":"Article 107218"},"PeriodicalIF":2.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population genetics of Macrognathus siamenis (Synbranchiformes: Mastacembelidae): Implications for non-migratory fishery resources in the Mekong River basin","authors":"Oanh Thi Truong ,&nbsp;Sang Quang Tran ,&nbsp;Kent E. Carpenter ,&nbsp;Quyen Dang Ha Vu ,&nbsp;Thuy-Yen Duong ,&nbsp;Mie Mie Kyaw ,&nbsp;Chaiwut Grudpan ,&nbsp;Van Ngo Thai Bich ,&nbsp;Binh Thuy Dang","doi":"10.1016/j.fishres.2024.107210","DOIUrl":"10.1016/j.fishres.2024.107210","url":null,"abstract":"<div><div>The spotted spiny eel, <em>Macrognathus siamensis</em> is an economically important freshwater fish in the Mekong River basin, which is undergoing dramatic biodiversity changes due to anthropogenic impacts. The species is non-migratory, with a moderate larval duration that facilitates downstream genetic connectivity. Restriction site-associated DNA sequence datasets that includes 3736 and 1244 single nucleotide polymorphisms representing putatively neutral loci, from all geographic sites and without the Tachileik site, indicate strong population structure in this sedentary fish, with a significant isolation-by-distance signature. This structure reflects isolation of tributary populations and downstream dispersal of these distinct populations to mix in the Mekong mainstem and contributes to increased genetic diversity in the lower reaches of the Mekong basin. Genetic data indicates that the dispersal of eggs and larvae downstream is not impeded by Khone Falls and that the falls prevent upstream dispersal of eggs and larvae. Despite this downstream connectivity, there is a strong population structure among above- and below-Khone Falls groups. An analysis of outlier loci putatively under selection provides evidence that the difference between connected metapopulations above and below the falls is due to the fundamental differences in environmental regimes. We hypothesize that instead of a physical barrier, the falls simply represents a demarcation between previously recognized upstream limited-floodplain environments and downstream extensive-floodplain environments. These findings emphasize the need to monitor genetic diversity of key sedentary fishery species to assess whether proposed dams along the river could affect genetic diversity downstream. This genetic diversity is particularly important for the resilience of downstream populations because of the many environmental impacts caused by dams, land use, and climate change. Early detection of reduced downstream genetic diversity could trigger remediation programs to ensure resilience and continued fisheries productivity of important non-migratory fish resources.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"281 ","pages":"Article 107210"},"PeriodicalIF":2.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The hovering pontoon trap: The tougher, younger sibling in the pontoon trap family","authors":"Peter Ljungberg ,&nbsp;Sven-Gunnar Lunneryd ,&nbsp;Lars Hillström ,&nbsp;Glenn Fridh ,&nbsp;Mikael Lundin","doi":"10.1016/j.fishres.2024.107214","DOIUrl":"10.1016/j.fishres.2024.107214","url":null,"abstract":"<div><div>Trap nets are a large, stationary, and fixed type of passive fishing gear that has traditionally been used for catching fish in shallow coastal environments. Despite their large size, catches are often retrieved using small boats, making them less energy demanding compared to active gear types. This, along with the stationary nature of the trap, allows for fishing with relatively low environmental impact due to minimal disturbance of the benthic community. The combination of minimal benthic impact, live catch, low fuel, and selectivity offers great potential for the development of sustainable coastal fisheries.</div><div>Here, we describe the development of the hovering pontoon trap, a fishing gear with a robust design to resist strong waves and currents, and usable in both shallow and deep waters to catch both pelagic and benthic species. We present results from early case studies targeting benthic Baltic Sea species, including perch (<em>Percha fluventaliis</em>), Atlantic cod (<em>Gadus morhua</em>) and vendace (<em>Coregonus albula</em>), showing similar or improved catches in relation to earlier studies. Further, we show that the hovering pontoon trap was able to withstand harsher conditions than previous bottom-set models, making it a possible solution for the targeting of benthic fish communities in coastal environments.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"281 ","pages":"Article 107214"},"PeriodicalIF":2.2,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Implementing a fishery improvement programme to manage the common cuttlefish (Sepia officinalis) in artisanal sea and lagoon fisheries: The case study of the Chioggia’s fleet","authors":"Emily Sepe ,&nbsp;Federica Poli ,&nbsp;Federico Calì ,&nbsp;Simone D’Acunto ,&nbsp;Carlotta Mazzoldi ,&nbsp;Matteo Barbato","doi":"10.1016/j.fishres.2024.107209","DOIUrl":"10.1016/j.fishres.2024.107209","url":null,"abstract":"<div><div>In the light of reducing the impact of fishery, artisanal fisheries hold great potential to achieve the sustainable use of marine resources if locally managed at sub-regional level (i.e., within the same province or fleet) and by implementing mitigation systems. The Chioggia small-scale fishing fleet represents a study case in an overexploited Mediterranean sub-region, operating both in the Venice Lagoon and the North Adriatic Sea. During the spawning period, this small-scale fishery targets the same target species, the common cuttlefish (<em>Sepia officinalis</em>), which, over the past thirty years, has shown a general decline in catch trends. Cuttlefish represent a high-value resource at all life stages, with both adults and juveniles considered targets of the artisanal fishery. Additionally, eggs are consistently laid on fishing gear during the breeding season and must be removed by fishers to prevent a reduction in fishing efficiency. These aspects contribute to the vulnerability of the common cuttlefish stocks, calling for a complementary management approach. We researched methods from the peer-reviewed literature, and adapted methods to reflect the environmental conditions of the sea and lagoon, and small-scale fishing methods. We combined into a complementary management approach: i) mitigation systems to reduce and collect eggs discarded during fishing operations, ii) semi-natural juvenile rearing diets to potentially release fishing pressure and support natural population, and iii) small-scale supply chain to both raise awareness about this resource vulnerability and promote the activity of fishers adopting virtuous behaviours. We tested these three functional management units in collaboration with lagoon and sea fishers and local stakeholders. We showed that the use of egg collectors, as an alternative spawning structure, performed well to limit the loss of the eggs laid upon the fishing gears. Second, we showed that Mixed and Natural diets contributed significantly to the growth rate of hatchlings compared to artificial diets. Finally, we demonstrated a shared interest in products derived from sustainable fisheries from the public, fishers and retailers. Therefore, the small-scale supply chain can represent a valid component to valorise the adoption of the whole management scheme. Overall, this complementary management approach can be adapted to and implemented in other local socio-economic communities of artisanal fishing in coastal environments worldwide. Complementary mitigation systems could work in synergy, overcoming the limitations of individual mitigation measures applied to diverse fishery resources.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"281 ","pages":"Article 107209"},"PeriodicalIF":2.2,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Predicting gear used in a multi-gear coastal fleet","authors":"P. Leitão ,&nbsp;A. Campos ,&nbsp;M. Castro","doi":"10.1016/j.fishres.2024.107199","DOIUrl":"10.1016/j.fishres.2024.107199","url":null,"abstract":"<div><div>Knowledge of the gear used in multi-gear fisheries is crucial for supporting fisheries management. Still, the high complexity and lack of data in the Portuguese multi-gear coastal fleet compromise this task. The present study developed a method to predict main fishing gear used in each fishing trip for the Portuguese multi-gear coastal fleet based on landing records (species caught, port, and month of landing). Landing records were used to predict gear (available for part of the fleet with electronic logbooks) using a machine learning model (random forest). This model was then applied to the remaining trips of the fleet, without electronic logbooks, to predict the gear used. A total of six gear types were considered: bivalve dredges, traps, gillnets, trammel nets, drifting longlines, and bottom longlines. The overall model prediction error was 14 %; bivalve dredges and longlines had the lowest errors, and trammel nets and gillnets were the highest. The study sheds new light on important aspects of the dynamics of this fleet, namely a decreasing trend in the use of longlines, poor electronic logbook coverage for some gear types, and greater diversity in the catches obtained with nets compared to other gear types.</div></div>","PeriodicalId":50443,"journal":{"name":"Fisheries Research","volume":"281 ","pages":"Article 107199"},"PeriodicalIF":2.2,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142528964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}