Danish Seine Research Articles

Fishing tactics and fish quality: The case of the coastal fishery for Atlantic cod in Norway

This study examined the effects of key fishing tactics such as the choice of fishing gear and catch size, an indicator of swift and intense fishing, on the quality of landed fish. The effects of changes in yearly TACs, and thus catch shares, vessel size (length) and vessel age on fish quality were also investigated. A data set consisting of objective quality assessments of Atlantic cod in 432 catches from the coastal cod fishery in Norway, combined with details about the same catches was analyzed. The statistical analysis showed that fishing gear affected fish quality, but to a variable degree, with gillnets and Danish seines, the preferred methods in this fishery, providing the poorest-quality fish. It was also found that catch size had a negative impact on fish quality for gillnets, handlines, and Danish seines, but not for longlines. The results indicate that fishers’ tactical decisions regarding what fishing gear to use, and how swiftly and intensely to fish, may lead to poor-quality fish being landed. Although this may be economically rational for fishers in a fishery with no restrictions on the choice of fishing gear and catch sizes, and where quality-based pricing is largely absent, it may lead to a substantial reduction in value-adding opportunities in downstream processing and marketing.

Morphology character and length-weight relationship of Goblinfish (Neovespicula depressifrons) Tetraogidae in Percut Sei Tuan Coastal, North Sumatera, Indonesia

The research was conducted in Percut Sei Tuan Aquatic with goblinfish (Neovespicula depressifrons) as the main object. Goblinfish was caught at a brackish aquatic which is mangroves are grown. This study aimed to analyse the relationship between weight-length, growth pattern, length-frequency distribution, and condition factors of goblin fish. Danish seines with mesh size net of 1 inch, ½ inch, and ¼ inch was used for fishing. After the fish caught, then measured the total length and weighed, measurements were conducted in the laboratory. The total length of fish caught is in the range of 24-65 mm and a weight of 0.2 - 3 g. The resulting group size consisted of 7 groups with class intervals of 42-47 mm is the mode group size. From the analysis of the length-weight relationship, the constant value of b = 0.972 and the value of the condition factor ranges from 0.90 to 1.37 with an average value of CF > 1.

Bioeconomic Model of Threadfin Bream Fish Resources in Banten Bay Waters

Threadfin bream or Nemipterus sp. becomes one of the fish resources utilized in Banten Bay waters. The catch of threadfin bream decreased from year to year. Therefore, threadfin bream resources in the Banten Bay waters have alleged over-exploited. This study aims to analyze the optimum utilization of threadfin bream fish resources, seen from three management positions namely maximum sustainable yield (MSY), maximum economic yield (MEY) and open access equilibrium (OAE). Bio-economic analysis was carried out using the Gordon Schaefer model. Economic parameters that used in this research are price and fishing cost. Biological parameters are estimated using the Schaefer model. The set gillnet, Danish seine, and trammel net are the fishing gear for catching the threadfin bream in this research. The result shows that the maximum sustainable yield of threadfin bream is 1,344 tons/year and the optimum effort is 2,298 units/year. The productions rate of threadfin bream from 2007 continued to decrease until 2016. The highest economic profit was obtained in MEY of IDR 12.9 billion. The actual condition of threadfin bream fisheries is still under the condition of MEY management. The utilization of threadfin bream can still be optimized, but it needs to be done carefully and wisely so as not to cause damage to fish resources and the environment. The decrease in catch and CPUE needs to be aware of symptoms of overfishing.

Modern specialized fishery of sea fish in the western Bering Sea

The shelf and continental slope of the western Bering Sea, being among the most productive areas of the Far-Eastern Seas of Russia, became exploited by commercial fishery half a century ago, after introduction of 200-mile exclusive economic zones in 1977 and relocation of the Russian fishing fleet from the eastern Bering Sea to its western part. In 2010-2019, about 20 % of the total catch of sea fish in the Far-Eastern basin (excluding pacific salmons) were caught in the West Bering Sea fishery zone. Among the fishery districts of the Russian Far East, this area is currently the 1st one by annual catch of pacific cod, grenadiers, sculpins and sablefish, 2nd— by catch of walleye pollock, halibuts and skates, 3rd— by catch of rockfishes, and 4th— by catch of pacific herring and flounders. Features of specialized fishery in the West Bering Sea fishery zone in 2010-2019 are clarified. Now 48 types of the specialized fishery can be distinguished here, while 96.3 % of the average annual landing is provided by the following 8 most important types: walleye pollock midwater trawl fishery (77.8 % of mean annual catch); pacific herring midwater trawl fishery (6.1 %); pacific cod bottom longline fishery (4.7 %); walleye pollock Danish seine fishery (2.7 %); grenadiers bottom longline fishery (2.4 %), pacific cod Danish seine fishery (0.9 %); squids bottom trawl fishery (0.9 %); and pacific cod bottom trawl fishery (0.8 %). All these types of fishery are highly specialized and portion of the target objects in the catches ranges from 76 to 96 % (according to official statistics), while the by-catch accounted as 4-24 %. The is no specialized fishery on such objects as rockfishes, arrowtooth and kamchatka flounders, and sablefish in the West Bering Sea fishery zone, but they are landed as by-catch. The fishery statistics with the data sorting to specialized fishery and by-catch can be used quite effectively for the stocks assessment and determining acceptable level of their exploitation, with recommendations for fishery regulation, including evaluation the possible level of non-specialized by-catch.

Some peculiarities of saffron cod <i>Eleginus gracilis</i> (Tilesius) biology and distribution on South-East Kamchatka

Analysis of Danish seine catches from the coastal waters of South-East Kamchatka has revealed all seasonal distribution of saffron cod connected to the sites of the continental sandbanks influenced by aquatic vortexes with increased benthic biomass, where the catches could reach 2.5 t/fishing operation. Based on the data of the trawl and Danish seine surveying, the stock abundance, the occurence frequency, the catches of saffron cod and the contribution into the total catch in the area mentioned increased in the fall-winter period, but could not be characterized as significant. In the period of the research (2003–2018) the Danish seine catches of saffron cod varied as 1–189 t, averaged 31.8 t. The fish in the Danish seine catches had the body length from 11 to 56 cm and the body weight from 20 to 750 г. The mean length and weight of saffron cod in summer was 30.8 cm and 241.7 g and in winter – 31.2 cm and 301.6 g respectively. Occurrence of independent reproductive groups of saffron cod in the coastal bays and on the shelf of South-East Kamchatka can be suggested based on the data of stock abundance distribution, differences in the size composition and the time of maturity.

Состояние техники и организации снюрреводного лова в прикамчатских водах

As a result of systematic monitoring of the parameters of the of Danish type danish seine equipped with sensors of ScanMar catch control system for the first time, the actual (working) vertical and horizontal openings of Danish type danish seine are instrumentally determined, as well as the working form of the danish seine in the process of running down and hauling wires. It has been shown that the horizontal opening of the Danish-type danish seine at the moment of the end of the running down wires is on average 21.2 m, the vertical one — 5.3 m, which suggests that in the process of further towing of the snurrevod its working form makes it possible to successfully catch aquatic organisms. The state of modern danish seine fishing, the qualitative and quantitative changes of the fleet structure on a danish seine fishing are analyzed. A sharp increase in the use of Danish-type danish seine structures with shortened wings and large vertical opening was recorded on the Kamchatka shelf. 2005 to 2018 the number of vessels involved in the danish seine fishing decreased by 53%, of which the small small fleet decreased by 120 units, the small class fleet — by 33 units, while the number of middle class vessels, on the contrary, increased by 8 units.

Does cantrang trawl fishing become more efficient after the partial trawl ban? a case study of technical efficiency of cantrang fishery in the Java Sea – Indonesia

Cantrang- a modified Danish seine that targets demersal fish and squid in the Java Sea- has been banned partially in all Indonesian waters since 2015. The policy goal was to limit the ecological impact by reducing the number of the fleet. This study compares the technical efficiency (T.E.) of cantrang fishing before and after the ban and identifies input technology that affects fleet efficiency. A Data Envelopment Analysis (DEA) was used to calculate the Technical Efficiency of the cantrang. In this case, the T.E. measures the ability of cantrang to maximize catch using a given set of production inputs such as Goss Tonnage (G.T.), fishing duration, and the number of skippers using the time series daily landing data from 2007 to 2017. The results show pure and scale efficiency of the fleet increases considerably during the after-ban period compared to the before-ban period. This relatively high technical efficiency at post-ban occurred due to the meaningful reduction of fishing days while optimizing the number of onboard skippers per vessel. Although the portion of skippers per vessel increases substantially at post-ban, this growth minimizes the onboard fishshorting, packaging, and grading works. Therefore, these tasks can be done faster than before.

Condition of shrimp commodity capture fisheries in pangandaran regency, West Java

The high potential of capture fisheries makes Pangandaran have abundant fishery resources. One of the excellent commodities in Pangandaran is shrimp and is an economic source for fishermen. This research was conducted to see the condition of shrimp commodity capture fisheries in Pangandaran Regency. The research was carried out in August-October 2019 at Pangandaran Regency Waters with the main focus on shrimp. The method used in this research is the case study method. Data used consists of primary data and secondary data obtained from the local department. The research results shows that the fishing gear used by Pangandaran fishermen to catch shrimp is 459 units of bottom gill nets, 315 units of trammel nets, 25 units of danish seine, and 27 units of beach seine. The fishing vessels which are mostly operated by fishermen in Pangandaran Regency is 1919 types of fishing vessels with a size of

Fishers\u2019 responses to the Danish seiner ban and the history of fisheries governance on the Java north coast

In 2015, the Indonesian government announced that it would prohibit the operation of the so-called cantrang (Danish Seine). The stated purpose of the cantrang ban was to make marine fisheries more environmentally sustainable. In response, cantrang fishers along the north coast of Java staged mass protests, and after 3 years of negotiations and uncertainty, the government exempted the cantrang fleets on the Java north coast from the policy. This paper analyses fishers’ responses to the ban from a historical and ethnographic perspective. Specifically, it compares the cantrang ban to two earlier government interventions in the fisheries on the Java north coast, one in 1905, the second 1980/81. With each intervention, a new governance principle was introduced to small-scale fisheries, established elites transferred their capital elsewhere, and new elites emerged who supported the new principle locally. Since 2015, however, only very few members of the established elites have exited the cantrang fishery, and no members of a new local elite have emerged yet who would support sustainability as a governance principle for fisheries. The paper aims to clarify why this was the case. More generally, it suggests that understanding the history of fisheries governance on the Java north coast requires attention to the role of local elites, and therefore to social differentiations among fishers.

Competition in a fish auction: The case of Atlantic cod in Northern Norway

This study investigates the role of bidder numbers in fish auctions, a neglected area of past research and one that is of key importance for optimal use of limited marine resources. The study of a Norwegian auction for Atlantic cod shows that prices increase when two or more bidders participate in the auction. Holding other variables such as lot size, quality grade, and seasonality constant, price increases of 4.51 %, 6.47 %, 7.18 %, and 9.88 % in auctions with two, three, four, and five plus bidders were found, compared to auctions with only one bidder. The increasing prices following from higher bidder numbers also indicate that fishers should be incentivized to provide high-quality fish at the right time of importance for optimal resource use. Increased competition also means that, over time, winning bids will be placed by the buyers that are the most capable of adding value and earning profits, which also contributes to optimal resource use. Findings also show to what extent factors such as lot size, quality grade, fishing method (bottom trawl, longline, Danish seine), and seasonality influence the probability of two or more participating bidders in auctions, which should be highly relevant information for fishers and policy makers.

Seafood certification schemes in Japan: Examples of challenges and opportunities from three Marine Stewardship Council (MSC) applicants

While there has been a global proliferation of marine certification schemes aiming to incentivize sustainable fishing in the last decade, the uptake has been comparatively slow in Japan. Suggested reasons include difficulties assessing Japanese fisheries co-management institutions, and reduced profitability from complex seafood distribution networks and mismatched consumer preferences. However, a few Japanese fisheries have been awarded the international Marine Stewardship Council (MSC) certification. This paper investigates the motivations and experiences of three such MSC applicants: the Kyoto Danish Seine Fisheries Federation offshore fishery, Ishihara Marine Products skipjack and albacore pole and line fishery, and Maruto Suisan rope grown Pacific oyster fishery. Semi-structured interviews were conducted with key informants from each case study and coded into motivations, problems and impacts. It was found that although there were economic motivations to apply for the certification, this mainly involved increasing domestic distribution channels rather than gaining or retaining access to premium-paying foreign markets. The co-management system that governs the Kyoto fisheries hampered the re-certification process of the fishery due to the difficulty of influencing the higher levels of management within the system. It also became clear that the type of applicant was important to consider: the two more recent MSC clients – both seafood processors – are better placed in the value chain to utilize the certification and its logo, and therefore more likely to financially sustain the certification. The study provides an important insight into the applicant experience of certification schemes in countries with lower consumer demand for them, such as Japan.

Catch composition and relative biomass of fishes caught by danish seine in Lingayen gulf

The Lingayen Gulf is one of the major fishing grounds in the Philippines. The main clients of the fishing ground are the fishermen in the province of Pangasinan. The bulk of the catch of these fishermen are caught mainly using Danish Seine. Though there have been study conducted, related or succeeding studies were not undertaken so far. In the absence of updated studies, weundertaken a study to assess the catch composition and relative biomass of fishes caught by Danish seine. Two Sampling sites were selected, namely, Sector I (western Coast) and Sector III (eastern Coast). Two 45 HP commercial fishing vessels were utilized in the study in two sectors of the Gulf. Each vessel utilized modified Danish seine net and sampling was done every 15 days for a period of two months. The landed catch volume of every species were obtained from the fishing vessel’s logbook. Results showed that there were 38 species of finfishes belonging to 22 families identified in the two sectors (25 species in Sector I and 29 species in Sector III). Decapterus macrosoma yielded the highest catch for the whole sampling periods and the most dominant catch in Sector I, while Saurida tumbil in Sector III. Catch landings were higher in Sector I with 6,448.6 kg as compared to Sector III has 2,525.8 kg. Out of the 22 families identified, 14 of these were demersal while the remaining were pelagic. Two new families were identified in this study which not mentioned in the early studies. Due to the limitations of this study, further studies related on the growth by sexes and other important growth parameters of different species is recommended for better management of the Lingayen Gulf.

Length-weight relationships of marine fishes caught by danish seine in Lingayen gulf

The length-weight relationship were analysed for each marine fishes caught by Danish Seine, using specimens collected from the Magsaysay Market, Dagupan City, Pangasinan. Two Sampling sites were selected, namely, Sector I (western Coast) and Sector III (eastern Coast). Two commercial fishing vessels were utilized in the study; one each in Sector I and Sector III. Sampling was done every 15 days for a period of two months. The length-weight relationship, determined by the regression analysis were evaluated for each major fishes. In Sector I, the length and weight relationship for Decapterus macrosoma, Sphyraena barracuda, Rastrelliger kanagurta, Decapterus kurroides and Nemipterus bathybius was growing in a negative allometric way except of the Rastrelliger kanagurta that grows in positive allometric way. In Sector III species of Saurida tumbil, Rastrelliger brachysoma, Trichiurus lepturus, Nemipterus bathybius and Sphyraena barracuda) Sector III grows in negative allometric way. In addition, most of the species shows a strong positive correlation this indicates that as the length increases, weight also increases.

Development and Impact of the Marine Stewardship Council (MSC) Certification on Japanese Fisheries A Case Study of the Kyoto Danish Seine Fishery Federation (KDSFF)

Development and Impact of the Marine Stewardship Council (MSC) Certification on Japanese Fisheries A Case Study of the Kyoto Danish Seine Fishery Federation (KDSFF)

Fishing methods for Atlantic cod and haddock: Quality and price versus costs

This study explores trade-offs between fish quality, fishing efficiency, costs and profitability across three different vessel groups in the Norwegian groundfish fishery, that is, vessels fishing with bottom trawls, longlines and Danish seines. The results of hedonic price analysis at the ex-vessel level of the value chain indicate substantial differences in fish quality as Atlantic cod caught with longlines obtain price premiums of 15.0 % and 12.6 % compared with bottom trawling and Danish seining, respectively, holding other variables constant. For haddock, longlining obtains a price premium of 20.0 % compared with Danish seining and 13.3 % compared with bottom trawling. However, despite better quality and prices, the costs of fishing are substantially higher for longliners than for bottom trawlers and Danish seiners, which explains the differences in profitability favoring the more technically efficient bottom trawlers and Danish seiners. Policy implications are discussed considering trade-offs between fish quality, ex-vessel prices and vessel profitability. In a highly regulated fishery such as the Norwegian groundfish fishery, with individual vessel and vessel group quotas based on historical fishing rights, policy intervention is important for optimal use of limited fish stocks but is not necessarily straightforward.

Bycatch sea cucumber Holothuria scabra processing and the quality characteristics

Sea cucumbers are marine invertebrate animals that have high economic value. Indonesia is the main exporter of trepang over the world; however, this trepang export has not yet contributed to the improvement of community welfare. The low quality of trepang produced by Indonesia makes the economic value of trepang was still low. The low quality was caused by changes in processing stages due to decreasing the wild catch. Since the ban of the mini trawl use (cantrang), fishermen only process the bycatch sea cucumbers Holothuria scabra or sandfish. Trepang produce from sandfish is the most expensive one; the price can reach 3-5 million per kg. The study aims to analyze the quality and analyze the potential of developing the quality of trepang produce using sandfish. The decrease in sandfish catch volume after the Danish seine ban prohibits the stage changes in sandfish processing. Elimination of fumigation stage, the addition of storage in the refrigerator, addition of boiling, overcooking, and using excessive papaya leaves, were the main causes of less than the minimum value specified in SNI for appearance and odor characteristic. Although water, ash, protein, total plate count, Salmonella content, Lead, and Cadmium are in the decent range, the exporters still buy trepang at lower prices because exporters have to do reprocessing to improve the quality.

The local effects of an innovation: Evidence from the French fish market

In this paper, we investigate the effects of the Danish seine which was introduced for a subsample of vessels on a single wholesale fish market in France. The goal was to mitigate the decrease in vessel profits due to the rise of gasoline prices. Estimations are conducted from transaction data over the 2009–2011 period during which the innovation was introduced. Using a difference-in-differences approach around the discontinuity, we find that the innovation has a large positive effect on quality, prices and profit of treated vessels. However, a shift in caught fish species is observed and new targeted species are fished very intensively. This suggests that quota management is needed to ensure the sustainability of fishing practices involving the new technology in the long run.

Biology characteristic, abundance index and fishing aspect of donkey croaker (Pennahia aneaBloch, 1793) in the Tangerang Waters

Pennahia aneain Tangerang waters have a fork length between 9.4 and 23 cm, with an average of 18.9 cm and modus 18-18.5 cm. Growth type is isometric with correlation R2= 0.7266 and b = 3.2251. The sex ratio of female: male = 1: 0.9. Level and index maturity of gonad are highest in February and lowest in March.The length first maturity of donkey croaker at 15.8 cmFL. The length of the first capture (Lc) by danish seine net at 16,76 cmFL and by gill net at 17.60 cmFL. Asymptotic length (L∞) at 23.89 cmFL and growth rate (K) = 0.84 per year. Mortality rate; total (Z) = 4.01, natural (M) = 1.73/year and by fishing (F) = 2.28/year. Exploitation rate (E) of donkey croaker fish is 0.57. CPUE the smallest in July was 0.41 kg/trip/day, the largest was in June 9 kg/trip/day, averaging 3.3 kg/trip/day. The fishing season from July to January with its peak in November and the famine season occurs in February-June with a peak in February. The main fishing gear for catching donkey croaker fish in the Tangerang waters is the danish seine net. The highest production of donkey croaker fish in June.

Performance analysis of small pelagic fishing unit in Tawang fishing port, Kendal Regency

Kendal Regency holds relatively large potential, especially small pelagic fisheries. One of the main bases of the capture small pelagic fisheries industry is Tawang fishing port (PPP). However, many fishermen still use mini trawl that can cause problems related to fish resources, social and environmental. The purpose of this research was to determine the best type of small pelagic fishing unit from technical, environmental, socio-economic and financial aspects in PPP Tawang, Kendal Regency. The research method used was a survey method using descriptive and scoring analysis. The sampling method used was purposive and snowball sampling. Based on the analysis, it was found that the purse seine gets priority I with a value of 12.27, priority II pelagic danish seine with a value of 11.87 and priority III of gillnet with value of 9.67. In conclusion, purse seine is the best small pelagic fishing unit in PPP Kendal.

Bio-economic model of Danish seine and purse seine fisheries in Rembang Regency, Indonesia

The fisheries in Indonesia is multi-gears fisheries, including in Rembang Regency. Rembang Regency had fishery production of 36,243 tons in 2017 and very dependent on purse seine and Danish seine fisheries. Although they have different fishing operation, but types of fish caught by purse seine and Danish seine are partly of the same species. The interrelation of fish species caught shows the risk of interrelation between purse seine and Danish seine (negative externalities) which can encourage overfishing. The purpose of this research was to make the model of relationship between Danish seine and purse seine fisheries in Rembang Regency with a bio-economic approach. We have modified Gordon-Schaefer model (single gear) to be a multi-gears model that can explain the reciprocal relationship between Danish seine and purse seine fisheries, and also we did optimization of production and profit. This research has proven that Danish seine fishing efforts have a negative impact on the production of purse seine fisheries, and vice versa. The combination of 328 units of purse seine and 304 units of Danish seine will produce optimal aggregate production (62,286 tons per year). While the combination of 176 units of Danish seine and 348 units of purse seine will generate an aggregate profit of IDR 510 billion per year as the win–win solution for both Danish seine and purse seine fisheries. The highest aggregate profit will occur at 370 units of purse seine fisheries and 0 units of Danish seine, which will generate a profit of IDR 535 billion per year.