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The Sea of Marmara (SoM) holds significant importance for both local and regional fisheries due to its characteristic as a semi-enclosed sea on the migratory route of small and medium pelagic fish. While this area sees active fishing with numerous small-scale vessels and approximately 150 purse seiners, there has been a noticeable absence of research on the spatial and temporal distribution of intense fishing pressure in this relatively small sea. Concerns regarding the sustainability of purse seining in the region, specifically in relation to its potential interaction with the seafloor, have emerged over time. This study aimed to assess the spatial and temporal distribution of purse seine fishing effort in the Sea of Marmara (SoM) from 2012 to 2022. The objectives were to identify the locations of concentrated purse seine fishing effort, determine if these clusters were statistically significant hotspots, and uncover any spatio-temporal variations in fishing activity. To address these issues, this study assessed the apparent fishing effort of purse seiners from 2012 to 2022 using data from Global Fishing Watch. Various statistical tools of geographic information systems (ArcGIS and QGIS) were applied to achieve the following. identify the locations where apparent clusters of purse seine fishing effort were concentrated in the SoM; determine if these identified clusters were statistically significant hotspots; and uncover any spatio-temporal variations in fishing activity. The analyses revealed persistent and intensifying purse seine fishing efforts concentrated in the eastern sector of the SoM. This area includes ecologically sensitive habitats and serves as a habitat for vulnerable species, such as Posidonia meadows, Pinna nobilis, and Octocorals. Additionally, it was found that 50% of the fishing effort occurred in areas shallower than 50 m, raising public concerns about the protection of these specific zones. The findings indicate significant and increasing fishing pressure in the eastern sector of the SoM, posing potential risks to sensitive marine habitats and vulnerable species. These results underscore the need for targeted management strategies to ensure the sustainability of purse seine fishing and the protection of critical habitats in the SoM. [ABSTRACT FROM AUTHOR]

Objective: Little Tunny Euthynnus alletteratus is a commercially viable species, and its research has been prioritized by the International Commission for the Conservation of Atlantic Tunas. This study aimed to evaluate the stock status of Little Tunny in the Northeast Atlantic Ocean, the effectiveness of the life history priors, and the sensitivity of the model's predicted reference points to prior misspecification. The findings could help reduce uncertainties regarding the state of Little Tunny in the region. Methods: We used empirically estimated life history parameters and purse‐seine fish aggregating device (FAD) and free school fishing length‐frequency data from 2000 to 2021, available in the International Commission for the Conservation of Atlantic Tunas database. We applied the length‐based Bayesian biomass (LBB) and length‐based spawning potential ratio assessment methods. Result: The LBB's outputs indicate that Little Tunny was grossly overfished at the exerted fishing pressure. This was corroborated by length‐based spawning potential ratio estimates of low spawning per recruit for the stock exploited by purse seines under FAD and free school sets. The reference points of both models were most sensitive to asymptotic length (L∞) prior misspecification, and including life history priors in LBB produced a narrower confidence interval of the estimated reference points. Conclusion: The Northeast Atlantic Ocean Little Tunny fishery exploited by purse‐seine fisheries under FAD and free school sets may be unsustainable. We maintain that user priors could reduce uncertainty in LBB, whereas accurate specification of priors, particularly L∞, is required to have less biased results using the models. We recommend catch limits through, for instance, spatial closures, but caution is advised due to uncertainty in this study's life history priors. Impact statementThe Little Tunny, a species with high research priority in the Atlantic Ocean, has significant tuna purse‐seine fishing grounds in the Northeast Atlantic Ocean waters of West African states. Because these countries are developing, there may not be as much research capacity available. The current findings may therefore be helpful to these states and pertinent international commissions in creating a fisheries management framework that is anticipated to eventually have a wider impact on sustainable production, ideally through regulatory and enhancement measures that support the social and economic well‐being of the coastal states and the industries that rely on the production. [ABSTRACT FROM AUTHOR]

Flying fish (Decapterus spp) is a type of catch with high financial value for the people of East Flores. Based on production data obtained in the 2017-2022 period, flying fish were recorded as the largest catch by purse seine fishermen when compared to other types of small pelagic fish. So research was carried out on the use of flying fish in Larantuka waters with the aim of finding out the value of using natural resources using the Gordon-Schaefer model of bioeconomic studies. The research technique used is descriptive analysis involving information on management of flying fish for 2017- 2022 by obtaining information such as effort and catch of flying fish as well as important information such as sales costs and functional costs. The results of bioeconomic testing of the Gordon-Schaefer model on flying fish show a CMSY value of 705.826 kg/year and a fishing effort of 1,278 trips/fishing gear, a CMEY value of 686.875 kg/year and a fishing effort of 1.069. trips/fishing gear and COAE worth 386.817 kg/year with a fishing effort of 2.137 trips/fishing gear, while the level of utilization of flying fish (Decapterus spp) in Larantuka waters has reached 103% with the classification of excessive utilization and the level of effort at 41%. Based on exploration results, there are three types of flying fish in Larantuka waters, namely bluefin flying fish (Decapterus macarellus), yellowfin flying fish (Decapterus macrosoma), and redfin flying fish (Decapterus akaadsi) [ABSTRACT FROM AUTHOR]

Every fishing operation cannot be separated from the management process which is carried out in stages starting from planning, organizing, implementing and controlling so that fishing achievements can be met. Purse seine is a fishing tool that produces the highest fishery production at the Nizam Zachman PPS, Jakarta. Studies regarding the management process of fishing operations are still limited, so it is necessary to conduct studies regarding the management of fishing operations at KM. Mekar Kencana 03 at PPS Nizam Zachman Jakarta. Data collection was carried out by observing fishing activities in KM. Mekar Kencana 03 and interview. The data analysis used is qualitative descriptive analysis. Departure preparations are made 30 minutes before departure. The minimum number of crew members on a ship when fishing at sea is 32 people, including the captain. Supplies are prepared according to the number of crew members. The condition of the ship must be monitored, such as the main engine and axle engine. Ship permit documents must be prepared, fishing gear and ship navigation equipment must also be checked. Supervision of fishing operations is carried out directly by the ship owner who acts as the ship's captain. [ABSTRACT FROM AUTHOR]

I recount my personal history, beginning as a young fisherman, becoming an academic fisheries biologist, and ultimately a leader of institutions dedicated to marine and polar research, higher education, and advising policymakers. After my dissertation in the early 1990s, I embarked on an active research career at the Institute of Marine Research (IMR) in Bergen, Norway, developing a sonar method to estimate the abundance of schooling, pelagic fish. My career then transitioned to middle leadership—15 years as Section Leader and Research Director at IMR—followed by >10 years as a top leader for The University Centre in Svalbard, the National Institute of Nutrition and Seafood Research, and finally the Norwegian Polar Institute. I describe the major challenges, opportunities, and processes these leadership roles have entailed. I hope to send a positive message about the influential role of science, and the necessity of clear communication of results and advice at a time when there is a sense of urgency. [ABSTRACT FROM AUTHOR]

Fish catch data is crucial for analyzing policy decisions aimed at conserving available fish resources. The lack of quality data and information on fishing gear catches is a significant obstacle in fisheries management in almost all regions of Indonesia. This research aims to analyze the production, fish species composition, and productivity of purse seine fishing gear at Idi Fishing Port, using a case study approach. To achieve the research objectives, we analyzed catch data to determine the production and species composition of the fish caught using purse seine from 2018 to 2022. This study also compared the amount of catch production with fishing effort to determine fishing productivity. The study revealed that the purse seine method caught 14 distinct fish species, of which seven were target fish (pelagic fish) and seven were bycatch. Tuna, skipjack, and mackerel were the most commonly caught species, accounting for 95% of the total catch. Mackerel was the primary target fish species, with the highest production from a total catch of 31,611,140 kg. Pomfret had the highest bycatch production of 254,690 kg.

Muncar is the largest fish landing which produced Bali Sardinella (Sardinella lemuru) in Banyuwangi. Sardinella was caught by purse seine. During fishing by purse seine, target species was Bali Sardinella while another catch was called bycatch. Some researchers indicated that bycatch was one factor affecting fish stock depletion. The aim of this research was to investigate catch composition and size distribution of dominant fish caught by purse seine. Result of observation at 10 fishing trip indicated that catch of purse seine was dominated by Bali Sardinella (Sardinella lemuru) which total account of 3.360 fishes or 77,83 % as a target catch, and the bycatch is layang (Decapterus ruselli) about 596 fishes or 13,77%, and slengseng (Scomber australasicus) about 363 fishes or 8,40%. The size of lemuru who caught in this research is between 12-21 cm. Dominant caught at size 14-15 cm about 2.032 fishes (46,97%), and a least caught at >18 cm about seven fishes (0,16%). The size of layang who caught in this research is between 13-25 cm. Dominant caught at size 19-20,5 cm about 255 fishes (5,20%), and a least caught at size 23,5-25 cm about one fishes (0,02%). The size of slengseng who caught in this research is between 13-28 cm. Dominant caught at size 23-25 cm about 143 fishes (3,30%) and least caught at size 27-28 cm only two fishes (0,04%). [ABSTRACT FROM AUTHOR]

The regulations imposing sanctions for violations of provisions regarding the conformity of fishing grounds and areas for catching fish have not been fully complied with by fishing vessels based at the Sibolga Archypelago Fishing Port. The number of violations committed by purse seine vessels, categorized by size, is as follows: 34 violations for vessels sized 30-100 GT and 23 violations for vessels sized 100-200 GT. The purpose of this research is to analyze the status and conformity of purse seine fishing grounds at PPN Sibolga with fisheries management regulations. This research was conducted at the Sibolga Archypelago Fishing Port from January to March 2024. The research is quantitative in nature, using a descriptive method. Respondents are skippers and boat masters of purse seine vessels. Sample determination in the research was done through incidental sampling. Data analysis was conducted using scoring, weighting, and comparison. The results indicate that the potential status and conformity of Fishing Ground are as follows: Fishing grounds within <12 miles for small pelagic purse seine fishermen with vessel sizes of 30-100 GT are classified as potential but not in conformity with Ministerial Regulation No. 58 of 2020. Meanwhile, potential FGAs for small pelagic purse seine fishermen targeting skipjack tuna with vessel sizes of 30-100 GT and for large pelagic purse seine fishermen targeting skipjack tuna with vessel sizes of 100-300 GT are in conformity with Ministerial Regulation No. 58 of 2020. [ABSTRACT FROM AUTHOR]

An unmanned surface vehicle (USV) with a fish attraction lamp was developed to assist in the nighttime operations of a Japanese purse seine fishery. The USV weighs about 15 kg, is equipped with a 200 W underwater light-emitting diode (LED), and can be radio-controlled to move on the sea surface. The purse seiner shoots a net to surround the lighting boat to catch fish gathered by fish attraction lamps. The USV was deployed on the sea surface from the purse seiner during the net-hauling operation and replaced the lighting boat to continue fish attraction after shooting the net. The time required for each operation using the USV and conventional lighting boat operations was compared, and it was found that the time required for the lighting boat for fish attraction after shooting the net was reduced by about 10 min per haul when the USV was used. On the other hand, the time required by the purse seiner to shoot and haul the net and the catch amount did not change. The USV can contribute to time savings in operation and safety improvements in the purse seine fishery. [ABSTRACT FROM AUTHOR]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The incidental capture of non-target species (bycatch) in tuna fisheries impacts some marine vertebrates, particularly species with vulnerable life histories such as manta and devil rays (mobulids). There is broad interest in reducing mobulid bycatch in tuna purse seine fisheries, with existing efforts mainly focusing on reducing post-capture mortality rates. We explore a novel potential pre-capture mobulid bycatch avoidance strategy for the tuna purse seine fishery using communication between fishing vessels and associated spotter helicopters. We conducted a survey of tuna purse seine helicopter pilots, spotters, and fishers operating in the eastern Pacific Ocean (n = 33) to ascertain the ability of helicopter crew to detect mobulids prior to capture and communicate bycatch avoidance with vessel crew. Results indicate over half of the helicopter crew report being “always” or “sometimes” able to sight and identify mobulids and that helicopter crew regularly communicate mobulid sightings to the vessel already. Given that an average of 63% of class-6 vessel trips between 2017 to 2022 carried onboard helicopters, our results suggest that helicopter-vessel communication could be feasible and scalable for mobulid bycatch detection, enabling potential bycatch avoidance and early alerts for proper handling protocols. We also identify the potential use of helicopter detection to improve research efforts for mobulid conservation (e.g., data collection of population and habitat observations). This study is the first to investigate the utility of helicopter-vessel communication as a bycatch mitigation strategy for elasmobranchs and identifies research and management directions that could be further investigated to avoid bycatch of mobulids. [ABSTRACT FROM AUTHOR]

The incidental capture of non-target species (bycatch) in tuna fisheries impacts some marine vertebrates, particularly species with vulnerable life histories such as manta and devil rays (mobulids). There is broad interest in reducing mobulid bycatch in tuna purse seine fisheries, with existing efforts mainly focusing on reducing post-capture mortality rates. We explore a novel potential pre-capture mobulid bycatch avoidance strategy for the tuna purse seine fishery using communication between fishing vessels and associated spotter helicopters. We conducted a survey of tuna purse seine helicopter pilots, spotters, and fishers operating in the eastern Pacific Ocean (n = 33) to ascertain the ability of helicopter crew to detect mobulids prior to capture and communicate bycatch avoidance with vessel crew. Results indicate over half of the helicopter crew report being “always” or “sometimes” able to sight and identify mobulids and that helicopter crew regularly communicate mobulid sightings to the vessel already. Given that an average of 63% of class-6 vessel trips between 2017 to 2022 carried onboard helicopters, our results suggest that helicopter-vessel communication could be feasible and scalable for mobulid bycatch detection, enabling potential bycatch avoidance and early alerts for proper handling protocols. We also identify the potential use of helicopter detection to improve research efforts for mobulid conservation (e.g., data collection of population and habitat observations). This study is the first to investigate the utility of helicopter-vessel communication as a bycatch mitigation strategy for elasmobranchs and identifies research and management directions that could be further investigated to avoid bycatch of mobulids.

Tegal is one of the regencies in Central Java that possesses a considerable wealth of fisheries resources. The waters of Karang Jeruk are strategically important for the development of fishing in Tegal Regency, as they directly border the Java Sea, offering significant potential for abundant fishery resources. The use of portable FAD is expected to enhance the catch of fishermen, providing a solution to the declining catch experienced by purse seine fishermen in the waters of Karang Jeruk, Tegal. The aim ofthis research is to determine the composition of the catch and calculate the productivity of purse seine catches on portable fish aggregating devices. The research method employed is experimental fishing. Descriptive analysis was used to identify the composition of catch types and the quantity of each captured fish species. Catch productivity was determined by comparing the quantity of the catch with the duration of the catch operation. The results show that the main catch of purse seine consists of bullettuna, scads, anchovies, mackerel tuna, and squid. The composition of the catch indicates the presence of fish in the area where purse seine operations are conducted. The catch productivity values havean average of 900.8 kg/setting. [ABSTRACT FROM AUTHOR]

The aim of this research is to evaluate the purse seine operating technique on KM. Sumber Rezeki based on regulation of the minister of maritime affairs and fisheries no. 18 of 2021. This research was carried out using KM. Sumber Rezeki belongs to PT. HLS in 2022. The data collection methods used are observation and interviews. The result is the purse seine used by KM. Sumber Rezeki is a type of small pelagic purse seine with the regional name pukat langgar. The construction consists of 450 m top ris rope, 450 m lower rise rope, 450 m buoy rope, 450 m ballast rope, 450 m skid, 450 m ring rope, 1500 buoys, 700 ballast, 105 rings. Fishing aids of purse seine are permanent FADs and lights. The ship used is a motor ship measuring 168 GT. Fishing was carried out on line III and WPP 711. Based on the evaluation of the purse seine operation technique, seven aspects were declared appropriate, namely the mesh size and length of the line of rise were appropriate, the size of the vessel and the fishing line were appropriate. One aspect that is not appropriate is that the operation of the langar trawl is not equipped with a radar reflector as a fishing aid. [ABSTRACT FROM AUTHOR]

In the Mediterranean, one of the most prized small pelagic species is the European anchovy (Engraulis encrasicolus). This species has long been targeted by fishermen in the southern Alboran Sea and the Mediterranean Sea. The objective of this research was to identify any linkages that may exist between environmental changes in the southern Alboran Sea and the reported drop in anchovy landings between 1983 and 2020. The method of forward stepwise regression was used, taking into account environmental indicators, such as sea surface salinity (SSS), sea surface temperature (SST), surface chlorophyll a (Chl-a), U and V wind components, NAO index, and Atlantic jet velocity. To select the best prediction models, generalized linear models (GLMs) were created and organized based on their corrected akaike information criteria (AICc) values. Trended time data were used to create six top models, which explained 60 to 79% of the variation in anchovy landings. Temperature, salinity, and the U wind component all displayed a negative association with anchovy landings. On the other hand, the Atlantic jets' velocity as they traveled through the Strait of Gibraltar was positively correlated with anchovy landings. When the trend component was taken out; however, none of the environmental variables could explain the variations in anchovy landings. This may imply that while environmental influences have an effect over the long term, they have little effect on the inter-annual time scale. Hence, the decline in landings of this species may be due to factors other than environmental change. Overfishing may have played a substantial role in the long-term decline in landings since this species was the most targeted of the small pelagic species in the study area. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Social & Technology / Jurnal Sosial dan Teknologi (SOSTECH) is the property of Green Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Blacktip Sea Catfish (Plicofollis dussumieri) is one of the most abundant species of fish caught in all kinds of commercial nets, including gillnets and purse seiners, along the coast of the Oman Sea. To study the biological parameters of Blacktip Sea Catfish caught in commercial gillnet and purse seine and to compare them, 818 samples from gillnet and 300 sample from purse seine were collected from January to March 2020. The fork length range of P. dussumieri was 22.10-62.10 cm and 17.30-10.37 cm in gillnet and purse seine, respectively. The Asymptotic length (L∞) of P. dussumieri was 64.41 cm. Length at maturity (Lm50) of P. dussumieri was 32.5 cm. The results show, 40% of the fish in the gillnet and 92% of the fish in the purse seine were immature. The results of study show that in order to preserve the stocks of P. dussumieri, the mesh size of both fishing methods, especially the purse seine, should be revised. [ABSTRACT FROM AUTHOR]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Drifting fish aggregating devices (dFADs) are human‐made floating objects widely used by tropical tuna purse seine (PS) fisheries to increase catch of target species. However, dFAD use has several negative impacts, including increased potential for overfishing, higher juvenile tuna catch, higher bycatch compared to other PS fishing modes, ghost‐fishing, and generation of marine litter. Based on these impacts, some stakeholders, especially environmental non‐governmental organizations and other competing fishing industries, suggest that dFADs should be completely banned. We list the pros and cons of dFAD fishing; address how to improve current management; and suggest solutions for the sustainability of dFAD fishing in the long term. A dFAD ban would lead to major changes in the availability and sourcing of tuna for human consumption and decrease the licensing revenue received by many developing states. Most importantly, we argue that tools exist today to manage for, reduce or eliminate most of the negative impacts of dFADs (e.g., bans on discards, limits on active dFADs, biodegradable non‐entangling constructions, time‐area deployment closures, recovery programs, and full data transparency, among others). Management decisions based on sound scientific reasoning are needed to address the legitimate concerns surrounding dFAD use and ensure the sustainability of both pelagic and coastal ecosystems and tropical tuna PS fisheries. [ABSTRACT FROM AUTHOR]

As an ocean fishing port in practice, the management of Nizam Zachman has taken action to regulate fishing vessels and large pelagic purse seine fishing gear (a form of control on the application of fishing vessel seaworthiness) in an effort to ensure compliance with provisions on safety practices and the seaworthiness of fishing activities and to realize sustainable capture fishery management. This study aimed to examine and determine the priority strategy of PPS Nizam Zachman in implementing the seaworthiness of large pelagic purse seine vessels. The analytical method used is descriptive statistics using SWOT and AHP analysis. The results showed that the SWOT analysis based on the internal and external factors in the IFAS and EFAS matrices obtained factor values of 0.36 and −0.1, which were located in quadrant IV or the S-T strategy. By strengthening the role of PPS Nizam Zachman in complying with the rules for large pelagic purse seine fishing owners, with good supervision, the sustainability of fishery resources can be supported. The results of the AHP analysis of prioritizing the four implementation aspects of the fishing vessel seaworthiness policy are as follows: communication (0.346) by holding regular outreach; disposition (0.242) by systematically assessing the seaworthiness and need for evaluation; resource (0.234) by increasing the number and capacity of fishing vessel seaworthiness inspectors; and bureaucracy (0.177) by applying the rules of supervision with prevention via assistance to large pelagic purse seine owners. [ABSTRACT FROM AUTHOR]

One example of a purse seine with one boat and using lamps is currently employed at the Mayangan Coastal Fisheries Port (PPP Mayangan). Based on monitoring data from the PPP Mayangan, there has been a 13.9% increase in the use of purse seine fishing gear, rising from 216 units in 2020 to 246 units in 2021. Considering this data, a review of the purse seine fishing enterprise is conducted to evaluate its financial viability. The review includes financial analysis to determine whether the fishing operation is profitable or not. The purposive sampling method was used to collect data for the review, involving several field visits with interviews and observations of selected respondents. In total, 20 respondents representing purse seine fishermen at PPP Mayangan were chosen for the study. The findings of this study indicate that the purse seine fishing operations at PPP Mayangan generated a profit of Rp.28,310,000 over four trips, with a revenue cost ratio of 2.23, which suggests a profitable enterprise. The payback period for this business is 33 months, indicating a relatively quick return on investment. Based on the review results, it can be concluded that the purse seine fishing business at PPP Mayangan is a successful fishing enterprise with a fast return on investment, making it viable for maintenance and improvement. [ABSTRACT FROM AUTHOR]

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The thread herring Opisthonema oglinum (Lesueur, 1818) is a small pelagic fish distributed in the western margin of the Atlantic Ocean from the United States to Argentina. It is a target species for diverse commercial fisheries, including the Brazilian industrial purse seine fleets that operate in the Southeastern Brazilian Bight. To investigate the geographic variation in the thread herring populations in this fishing ground, sagittal otoliths were collected from two areas: Rio de Janeiro (RJ: 23°04′ S, 44°03′ W) and Santa Catarina (SC: 26°05′ S, 48°18′ W). Otolith shape analyses and multi-elemental signatures were statistically evaluated using elliptical Fourier descriptors and elemental/Ca ratios. Remarkable differences in the thread herring otoliths between the two areas were found. The previous scenario in which the thread herring constitutes a single panmictic population in the Atlantic Ocean is now debatable. The implications of these results in terms of rational fisheries management for this species are highlighted. [ABSTRACT FROM AUTHOR]

Fishery inspector logbooks were used to estimate fishing gear interaction rates for humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries for herring from 2011 to 2020. Estimated rates were applied to fisheries data to estimate fleet‐wide totals. Estimates showed that in a 10‐year period, a total of 78 humpback whales, 95% CI [41, 145] and 100 killer whales, 95% CI [63, 176] were entrapped in purse seines. Most whales were disentangled alive, with an estimated mortality of 5%, CV 0.69, 95% CI [0.0, 11.8] and 6%, CV 0.48, 95% CI [0.3, 11.9], respectively. The average yearly mortality over the study period was thus approximately 0.60 killer whales and 0.39 humpback whales corresponding to 0.008% and 0.007% of the respective abundance estimates for these whale species in Norwegian waters. Given the Potential Biological Removal sustainability limits of 98 humpbacks and 161 killer whales per year, it may be concluded that, by itself, the average yearly mortality incurred by these whale populations by Norwegian fisheries does not constitute a significant risk to either of these species, but bycatch in Norwegian purse seine fisheries may not be the only source of anthropogenic mortality. [ABSTRACT FROM AUTHOR]

Context: The growing demand for global food security has resulted in rising fishing intensity, sometimes leading to overexploitation of fish resources, including tuna. Increasingly, fishers are using anchored fish aggregating devices (aFADs) to improve efficiencies and reduce costs. Aims: To identify locations and use patterns of FADs and characterise aFAD usage in Indonesia and beyond. Methods: We identified general patterns of aFAD usage by tuna purse-seine, pole and line, hand-line and troll-line vessels operating in Indonesian waters through reviewing relevant literature and focal-group discussions. Key results: aFADs usage can be characterised by gear type and fishing strategy; vessel behaviour; equipment and spare parts for aFADs installation; association with light; trip duration, catch per unit effort (CPUE), ratio of live bait to catch, fuel consumption; existence of aFAD floats on board vessels and by-catch composition. Conclusions: aFAD usage has been widely adopted by both industrial and small-scale tuna fishers to efficiency. However, this efficiency comes at the cost of significant increases in catches of juveniles and non-target species, which raises sustainability concerns for Indonesian officials. Implications: Ultimately, quantifying the numbers, types and locations of aFADs is key to fisheries management to avoid overfishing, overcrowding and limit by-catch and fishing-associated waste. The growing demand for global food security has resulted in a rise in fishing intensity and the overexploitation of fish resources, including tuna. Increasingly, fishers are using different methods to improve efficiencies and reduce costs. However, some approaches may have unintended consequences for fishing sustainability. We identified several indicators that can be used to detect the use of anchored fish-aggregating devices and we discuss these with an eye to improving fisheries management and long-term sustainability. [ABSTRACT FROM AUTHOR]

Along with the development of the tropical tuna purse-seine fishery from the 1960s in the Atlantic Ocean and from the 1980s in the Indian Ocean, many projects and studies have been conducted to improve knowledge about the biology, migrations and dynamics of the stocks of target and non-target (i.e. bycatch) species taken in these fisheries. Since the 2000s, the European Union (EU) has been supporting Member States in the collection of biological data on species caught by their purse seine and pole and line fisheries, thus making it possible to have a long-term series of data. Biological data have never been saved by the different tuna commissions, unlike the catches by species and sizes by areas and periods. However, these data are essential to monitor the status of the fisheries and fuel the assessment models used by the tuna Regional Fisheries Management Organisations (tRFMOs) for the sustainable management and conservation of the fish stocks under their mandate.We combined historical (1974-1999) and current (2003-2020) datasets on the biology of tropical tunas and bycatch fish caught by large-scale purse seiners in the Eastern Atlantic Ocean (EAO) and Western Indian Ocean (WIO). The resulting Tunabio database is presented in the present data paper and contains all available morphometric and biological data collected on more than 80,000 fish individuals.

Usaha perikanan di Pelabuhan Perikanan Pantai (PPP) Larangan Kabupaten Tegal merupakan salah satu penunjang utama perekonomian masyarakat pesisir Tegal dan menjadi penyuplai bahan baku pengolahan ikan teri (Stolephorus sp.) nasi di daerah Pemalang dan Kendal. Hasil tangkapan utama kegiatan penangkapan ikan di PPP Larangan adalah komoditas ikan teri. Alat tangkap yang digunakan nelayan di PPP Larangan adalah payang dan purse seine. Kajian ini bertujuan untuk mendeskripsikan perikanan payang dan purse seine di PPP Larangan, menghitung nilai produktivitas hasil tangkapan payang dan purse seine pada penangkapan pagi dan malam, serta membandingkan tingkat efektivitas hasil tangkapan purse seine pada penangkapan pagi dan malam. Alat tangkap payang dan purse seine yang dioperasikan di PPP Larangan bersifat one day fishing serta terdapat dua waktu penangkapan yaitu penangkapan pagi dan penangkapan malam. Nilai produktivitas payang dan purse seine pada penangkapan pagi lebih besar dibandingkan dengan penangkapan malam. Tingkat efektivitasnya penangkapan pagi lebih efektif berdasarkan nilai produktivitas dibandingkan dengan penangkapan malam baik untuk alat tangkap payang maupun purse seine.

The main problem with purse seine operations is the erratic purse line pull time. This greatly affects the total catch obtained in each trip. Therefore, this study aims to analyze the correlation value of purse line pull time and total catch, then analyze the effect between the two. The research method used is experimental fishing for 3 months. The implementation time was carried out in March-June 2020. The data analysis used was correlation analysis, ANOVA and regression. The correlation value (r) between purse line pulling time and total catch is 0.72 (strong). Based on the ANOVA value, which resulted in significantly different values, the purse line pull time significantly affected the total catch. The purse line pull time factor affects the total catch by 52% and 48% is influenced by other factors. The linear regression equation is y = 6261.2 - 2.3102x. The value of constant b has a negative value, so each additional purse line pull time will reduce the total catch. The results of this study can be used as the basis for the development of purse seine puller technology to improve the effectiveness and efficiency of purse seine operations. [ABSTRACT FROM AUTHOR]

Lemuru fisheries in Bali strait has great potential especially for Pengambengan Fishing Port fishermen to exploit the fish massively. One of actions we can do is to prevent the sustainability of fish resources by using fishing gear for lemuru in length at maturity. The fishing gear who is used by fishermen in Pengambengan Fishing Port to catch lemuru is purse seine. Based on the data of lemuru average length is small size (14,9 cm), medium size (15,7 cm) and big size (16,4 cm). Based on literature, length at maturity of lemuru in Bali strait is 17,3 cm. This matter become the reason that it needs an improvement in mesh size and rope length customized to Ministerial Regulation of Marine and Fisheries No. 59 Year 2020. The head rope length that is used is 400 m, mesh size 0.75 inch. Based on the calculation of lemuru length at maturity, it must use mesh size 1.5 inch. The picture of modification purse seine net design made 100 times smaller than its real specification. [ABSTRACT FROM AUTHOR]

Purse seiners generally try to maximize their revenues by targeting multiple species, starting with the most valuable ones available. The technology and capacity of purse seiners can be exceptionally high for the stocks found in the Marmara Sea, Turkey's only inland sea, due to its small size and nearly totally enclosed nature. Due to their large capabilities, they are responsible for the majority of catches and hence declines from this sea and thus should be held responsible for the poor state of marine stocks in the region. This study examines the catch compositions, expenses, and revenue sharing of purse seiners by using one representative vessel class for each of the four vessel length categories in the Marmara Sea. Surveys were also conducted with purse seine fishers to assess their perceptions related to fisheries management strategies along with their ideas for transitioning towards sustainable fisheries. As purse seiners are prominent stakeholders in the Marmara Sea fisheries, they should be incorporated into management guidance for effectiveness, along with other stakeholders. This study provides novel socio-economic data along with their perspectives, which may assist in improving policy decisions and capabilities. Our results demonstrate that purse seiners do not consider that their actions are a contributing factor to the current state of the fisheries, they trust in their amassed historical local knowledge, and seem to want to rebuild the resources, however only with minimal rules imposed on their sector. [ABSTRACT FROM AUTHOR]

This study aims to describe the relationship between the upwelling area and the ZPPI area of ​​skipjack tuna using the Generalized Additive Model (GAM) method and to map out the distribution pattern of skipjack in Barru waters, Makassar Strait. The research was conducted in November and December 2020, located in Barru waters, Makassar Strait. The research method used two methods by collecting primary data in the form of catches by following the purse seine fishing operation in Barru and secondary data in the form of satellite imagery data on sea surface temperature and chlorophyll-a. The data were analyzed using the GAM and upwelling area analysis. The upwelling area was obtained from the combination of the referred values of the two parameters. The results showed that sea surface temperature parameters had a significant effect on the catch of skipjack tuna with favored range of 28.5 - 29.7 oC. Preferred chlorophyll-a ranged from 0.15 to 0.23 mg m-3. We found that the upwelling event in the Flores sea does not have a direct effect on the distribution pattern of skipjack tuna, there is probably a time lag required after upwelling in which in turn has an impact on the distribution of skipjack tuna in the southern Malassar Strait. Keywords: skipjack distribution, Makassar Strait, upwelling area, Flores Sea, potential fishing zone area

This research focuses on the relationships between fishing success and various influential factors by using a statistical model based on observed data. The potential factors that significantly impact fishing success results were determined using in situ dataset collected with geographic coordinates in 126 fishing operations by three purse seines. A generalized additive model (GAM) for catch variables of Atlantic bluefin tuna Thunnus thynnus (presence–absence) was used to analyse fishing success under different variables: fishing operation (shooting duration, closing the racing duration, setting speed, sinking speed), gear design (length–height ratio), geophysical coordinates (latitude and longitude) and environmental conditions (sea surface temperature, depth, current speed at 10 m). The best fit model results showed that sea surface temperature makes a major contribution to the successful fishing of T. thynnus, as evidenced in previous work. In addition, some other factors (depth, shooting duration, closing the lacing duration, current speed at 10 m, setting speed, sinking speed, and length–height ratio) also affect the success of T. thynnus fishing in the Eastern Mediterranean Sea. These results help to indicate several fishing strategies that will be adopted to encourage fishers to increase their efforts. [ABSTRACT FROM AUTHOR]

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Research on comparing value of variable multiplier coefficient V in determining Gross Tonage (GT) value using equation 3 according to provisions of the Minister of Transportation Number 8 year 2013 was carried out at Larangan Beach Fishing Port, Tegal, Central Java. N = 42 samples were taken of various sizes of purse fishing boats with a GT of 6-20. The research is focused on comparing the multiplier coefficient V according to equation 3 of 0.25. The results showed that the coefficient multiplier V for purse seine ships in Larangan was 76% (Coefficient = 0.23-0.25), the value is close to the standard coefficient value of 0.25. Consists of 19% = standard coefficient of 0.25; 57% below the standard coefficient value (0.23-0.24) < 0.25. [ABSTRACT FROM AUTHOR]

Abstract Fishing ensures necessary food for humans and is inextricably linked with the environment because coastal communities developed special fishing procedures to achieve better exploitation of the aquatic resources. Lake Trichonis, Greece’s largest natural lake, is a freshwater ecosystem in which a marine species (Atherina boyeri) has entered and dominate the ichthyofauna. This species is exploited by purse seine fishing with the use of light, and previous studies revealed that the fishing lights create a particular food chain reaction, which promotes predation among the attracted fish species, one of which is Scardinius acarnanicus that preys upon A. boyeri. The purse seine fishers typically return to the lake alive S. acarnanicus, due to its low market demand, although it is the main predator of their catch. This custom, apart from causing income losses, promotes instability in the fish populations, while eventually altered the foraging behaviour of S. acarnanicus and made it a fish-predator instead of a typical omnivorous species. Based on data from official fish landing recordings, interviews with local fishers, and responses to questionnaires completed by residents of villages around Lake Trichonis, the present study investigates how changes in the dietary habits of the lakeside communities over time have led to the low market demand for S. acarnanicus. The present findings revealed an interesting relation between the dietary preferences of the local population and their ecological consequences for the fish community of this lake. This will eventually lead to the increase in the top predator (S. acarnanicus) and an inevitable decrease in the main catch (A. boyeri), affecting not only the ecological status of the lake, but also the socioeconomic characteristics of the human populations in this area. From another perspective, the results demonstrate a paradigm of adapted evolution by a wild fish under the pressure of human activities.

The catches of the Spanish purse seine fleet targeting tropical tunas in the Indian Ocean have been systematically sampled in port and at sea by scientific research centres since the fleet began to operate in the 1980s. During these samplings, some silky shark (Carcharhinus falciformis) specimens were found in the wells of these vessels which had not previously been recorded by at-sea scientific observers. To quantify the occurrence of these undetected incidental catches of silky sharks, this study compared two sets of data: on-board data collected by scientific observers and port sampling data. The European Union's long-term data collection program (PNDB), coordinated by the Spanish Fisheries Secretariat, provides on-board data collected by scientific observers as well as port sampling data which is collected while a vessel arrives to the port to begin unloading. The sampling focused on target species up until January 2021, when sampling started including non-target species as well. The datasets examined in this study are from January 2021 to December 2022. The results show significant differences between silky shark sizes observed on-board and those measured in port. A logistic model indicates a significant probability of observing silky sharks in wells, with a strong goodness of fit and high discrimination capacity as a function of the total catch of the fishing operation. Further analysis reveals differences in average sizes and weights of silky sharks caught in free-schools compared with those caught with tuna schools aggregated beneath Fish Aggregating Devices or FADs. The presence of unnoticed silky sharks suggests unreported captures, indicating that rates of mortality of the species are underestimated. In conclusion, the research emphasizes the need to address undetected silky shark bycatch in the purse seine fishery in the Indian Ocean. Obtaining accurate data and understanding the magnitude of this bycatch are crucial for developing management strategies that mitigate the impact and promote the sustainability of silky shark populations in the region. • Since 2021, a fraction of silky shark catch has been sampled in Spanish tropical tuna purse seine vessels in the Indian Ocean. • The average size of the sharks found in the wells is smaller than those discarded, which likely accounts for their oversight. • The study found unreported catch of silky sharks, causing underestimation of mortality rates not fully accounted for in reports. [ABSTRACT FROM AUTHOR]

Background Along with the development of the tropical tuna purse-seine fishery from the 1960s in the Atlantic Ocean and from the 1980s in the Indian Ocean, many projects and studies have been conducted to improve knowledge about the biology, migrations and dynamics of the stocks of target and non-target (i.e. bycatch) species taken in these fisheries. Since the 2000s, the European Union (EU) has been supporting Member States in the collection of biological data on species caught by their purse seine and pole and line fisheries, thus making it possible to have a long-term series of data. Biological data have never been saved by the different tuna commissions, unlike the catches by species and sizes by areas and periods. However, these data are essential to monitor the status of the fisheries and fuel the assessment models used by the tuna Regional Fisheries Management Organisations (tRFMOs) for the sustainable management and conservation of the fish stocks under their mandate. [ABSTRACT FROM AUTHOR]

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purse seine fishery in the Mediterranean represents about 60% of the international catch for Atlantic Bluefin Tuna (Thunnus thynnus). Yet, tagging operations from this segment of the fisheries remain rare and despite its potential importance for management, several aspects related to the migratory behavior of Atlantic Bluefin Tuna from these areas remain unaddressed. In the present manuscript, we report the results of two tagging operations carried out on a commercial purse seiner during two consecutive years in the spawning ground around the Maltese islands in the Central Mediterranean Sea. During these operations, eight individuals were tagged and the results showed that the larger fish (> 200 cm) undertook large-scale migrations outside the Mediterranean, whereas smaller individuals did not. This study suggests that size might affect the migratory behavior of Atlantic Bluefin Tuna, and underlines the potential of large-scale tagging operations from spawning grounds to address scientific questions having significant management implications. [ABSTRACT FROM AUTHOR]

The observer programme onboard the Spanish tropical tuna purse seine fleet recorded the incidental catch of one adult megamouth shark Megachasma pelagios in December 2005 and two juvenile megamouth sharks in the eastern Atlantic in July 2016 and August 2018, respectively. The same fleet also bycaught an adult individual in December 2005 in the western Indian Ocean. The juveniles were caught relatively near to the coast, while the adult was caught in oceanic waters. The companion species in the fishing sets were elasmobranchs, tuna and billfish. [ABSTRACT FROM AUTHOR]

Pelagic fisheries in the area of the eastern part of the Adriatic Sea, more precisely in the Croatian fishing grounds, are one of the most important types of fisheries in Croatia. In this paper, the quantitative and qualitative structure of catches obtained by the „ciplara“ purse seine in the Croatian part of the Adriatic Sea was analysed between 2013 and 2018. According to the data collected, the largest catches by this fishing gear were made in the coastal area, precisely in the fishing zones/sub-zones A/A4, E/E2, F/F2, C/C4 and G/G1. 70% of the catches consisted of targeted species, which indicates that the studied „ciplara“ purse seine is a selective fishing gear. Biological analyses are given for four target species.

Excluding the jellyfish from the bunt-end is a common slipping process used in the Sea of Marmara purse seine fishery. For this aim, a sheet of netting piece, larger mesh size and thicker diameter, is rigged on the bunt-end of the purse seine net. The jellyfish mass on the netting piece are slipped by rolling over the headline (floating line) after partially hauling or drying-up the net while it is still in the water. In this study, the catch amount of this slipping was roughly estimated with the introduction of the slipping process only used by the purse seiners in the Sea of Marmara. There were eight successful purse seine operations conducted between 8 and 11 September 2018 in depth ranged 77 to 677 m. The percentage of landed species versus to jellyfish varied between 23% and 85%. The mean landed anchovy amount is 4379 (3756.6) kg for per operation. The mean slipped amount of jellyfish is 3812.5 (2404.4) kg. However, both anchovy (99.8%) and jellyfish (96.3%) are the vast majority species that landed and slipped, respectively. In the operations totally 100 boxes of anchovy (1180 kg) unintentionally was slipped with the jellyfish. In addition, two sharks with larger size were slipped to the sea as alive over the floating line of the net. Although slipping practised rarely in Turkey, all the purse seiner in the Sea of Marmara have to use the adapted slipped process to get rid of jellyfish. However, there are no records and scientific findings regarding slipped amount of the jellyfish. For this reason, this study is important to presented preliminary results regarding amount of the jellyfish. In conclusion, this study is extended completely the Sea of Marmara practised to understand the dimensions of jellyfish amount and slipping process.

Penanganan hasil tangkapan merupakan salah satu faktor yang mempengaruhi kesegaran serta kualitas ikan hasil tangkapan. Upaya yang dilakukan pemerintah dalam menjaga mutu produk perikanan adalah dengan mengeluarkan KEPMEN-KP 52A/2013 tentang Persyaratan Jaminan Mutu dan Keamanan Hasil Perikanan pada Proses Produksi, Pengolahan, dan Distribusi. Keberpihakan pemerintah dengan mengeluarkan KEPMEN-KP 52A/2013 diharapkan dapat menghasilkan produk perikanan yang baik, aman, dan sehat. Tujuan dari penelitian ini adalah mengetahui kegiatan penanganan hasil tangkapan dan mengetahui kesesuaian kegiatan penanganan di KM Bina Maju dengan KEPMEN KP 52A/2013. Metode penelitian yang digunakan adalah studi kasus. Objek atau lokasi kegiatan penanganan ikan di KM Bina Maju yang telah menerapkan prinsip 3C1Q Clean, Carefull, Cold, dan Quick. Kesesuaian kegiatan penanganan di atas KM Bina Maju dengan KEPMEN KP 52A/2013, adalah ketersediaan palka yang digunakan untuk penyimpanan hasil tangkapan yang terpisah dari ruang mesin dan ruang ABK. Hanya saja dalam palka belum dilengkapi dengan mesin pendingin air laut dan pengatur otomatis suhu udara. Kesesuaian SDM dengan KEPMEN KP 52A/2013 adalah kondisi ABK yang sehat, tidak merokok, dan tidak meludah di area penyimpanan. Ketidaksesuaiannya adalah kurangnya kesadaran dalam penggunaan pakaian kerja dan kegiatan mencuci tangan sebelum kegiatan penanganan hasil tangkapan.