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1

Waldo, Staffan, and Anton Paulrud. "ITQs in Swedish demersal fisheries." ICES Journal of Marine Science 70, no. 1 (September 17, 2012): 68–77. http://dx.doi.org/10.1093/icesjms/fss141.

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Abstract Waldo, S., and Paulrud, A. 2013. ITQs in Swedish demersal fisheries. – ICES Journal of Marine Science, 70:68–77. Individual transferable quota (ITQ) is a management measure that is widely discussed, not least in the reform of the European Common Fisheries Policy. While the system is expected to reduce overcapacity and improve economic performance, questions are raised concerning the future of small-scale fisheries. This paper uses a model for Swedish fisheries (the Swedish Resource Rent Model for the Commercial Fisheries, SRRMCF) where the economics and fleet structure in a potential Swedish ITQ-system are analysed. The model is an optimization model based on linear programming and data from the European Union's data collection framework. The modelling approach can readily be used by other member states. Three main conclusions can be drawn on how ITQs will affect fisheries: The fishing fleet measured in number of vessels will decrease by approximately 30–50%.Profitability will increase so that the fishing industry will be able to provide competitive wages and make a financial contribution to fisheries management.The system can be designed so that small-scale fisheries are not disadvantaged.
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2

Dharmadi, Dharmadi, Fahmi Fahmi, and William White. "BIODIVERSITY OF SHARKS AND RAYS IN SOUTH EASTERN INDONESIA." Indonesian Fisheries Research Journal 15, no. 2 (May 24, 2017): 17. http://dx.doi.org/10.15578/ifrj.15.2.2009.17-28.

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Indonesia has a very diverse shark and ray fauna and is the largest chondrichthyan fisheries in the world. Most of the sharis are caught by longlines and gillnets and rays are caught both as target, e.g. in the tangle net and demersal gillnet fisheries, and as bycatch in other fisheries such as in demersal and drift gittnet, trammel net a-nd long line fisheries.
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3

Luasunaung, Alfret, Mariane M. Kayadoe, Frangky E. Kaparang, and Marvin Lestaluhu. "Analysis of CPUE and Fishing Capacity of demersal fisheries in Kema 2, North Sulawesi, Indonesia." International Journal of Advanced Engineering, Management and Science 8, no. 10 (2022): 22–28. http://dx.doi.org/10.22161/ijaems.810.4.

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Capture fisheries should be a sustainable economic activity aspect to provide good benefits to future resources. Sustainable marine fisheries resources exploitation requires a utilization rate lower than their availability. Therefore, the exploitation rate should not achieve the recovery ability of the resources in certain time. In fishing activities, for instance, there is a guideline not to catch fish over the Total Allowable Catch (TAC), 80% of the MSY. Information on the potency and the fishing capacity of tuna fisheries can be useful for the sustainable management of the resources. Also, this information can be used as a consideration for further management of the potency. There are two purposes of the study: (1) to analyze the CPUE (catch per unit effort) of demersal fisheries in Kema 2, North Sulawesi, for prediction of their potency, and (2) to analyze the efficiency of fishing capacity of the demersal fisheries in Kema 2, The study was done in two stages. The first was done by analyzing the potency using CPUE method (Shaefer models) to obtain the MSY, optimum effort and TAC (total allowable catch); and the second was done by analyzing the fishing capacity of demersal fisheries using DEA method to estimate the efficiency level of the fishing boats and devices in Kema 2. The result showed that the potency of demersal fisheries in Kema 2 was 71,700 tons per year and the optimum effort was 72,964 trips. Fishing capacity in demersal fisheries occurred in Kema 2 for the last 12 years was inefficient, especially for 2001. This may be caused by some factors such as trip operation, fishing duration, oil consumption, crew and operational cost. So, to manage the demersal resources in Kema 2, the TAC should be 57,520 tons per year. Based on the result, to increase the fishing efficiency, we should take into account of above factors. We suppose that the good means is reducing trip operation, fishing duration, oil consumption, crew and operational cost.
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4

Cohen, Daniel M., Nigel R. Merrett, and Richard L. Haedrich. "Deep-Sea Demersal Fish and Fisheries." Copeia 1999, no. 3 (August 2, 1999): 843. http://dx.doi.org/10.2307/1447628.

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5

Zahara, Asha Aulia, Audya Septria Ningrum, Baiq Kharisma Afrilia Putri Zain, Ivonne Siswanty, and Selamet Kurniawan Riandinata. "Identifikasi Jenis Ikan Demersal dan Pengelolaan Perikanan Tangkap Berkelanjutan di Pasar Ikan Anaiwoi Kabupaten Kolaka." Journal of Marine Research 12, no. 3 (May 23, 2023): 422–30. http://dx.doi.org/10.14710/jmr.v12i3.37074.

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Perikanan tangkap adalah sumber daya yang dapat diakses secara terbuka atau milik bersama yang penggunaannya dapat mengalami penangkapan berlebih atau penangkapan ikan yang merusak jika ditangani tanpa menggunakan konsep yang ramah lingkungan dan berkelanjutan. Penelitian ini bertujuan untuk mengidentifikasi jenis ikan demersal hasil tangkapan nelayan dan mengetahui pengelolaan perikanan tangkap di perairan Desa Anaiwoi. Penelitian dilakukan pada bulan September hingga Oktober 2022 di Pasar Ikan Anaiwoi, Kabupaten Kolaka. Metode yang digunakan adalah metode wawancara dan dokumentasi. Berdasarkan hasil penelitian, terdapat 31 spesies ikan demersal yang termasuk dalam 12 famili. Jenis ikan yang paling dominan ditemukan dari famili Lutjanidae dan Lethrinidae. Secara umum hasil identifikasi perikanan berkelanjutan cukup baik, seperti alat tangkap, jenis kapal ramah lingkungan, lokasi penangkapan dan jenis ikan serta ukuran ikan yang ditangkap. Jenis perahu yang paling banyak digunakan nelayan adalah perahu motor tempel. Alat tangkap yang paling umum digunakan adalah tali pancing.Capture fisheries are openly accessible resources or common property whose use may experience overfishing or destructive fishing if handled without using environmentally friendly and sustainable concepts. This study aims to identify the species of demersal fish caught by fishermen and to determine the management of capture fisheries in the waters of Anaiwoi Village. The research was conducted from September to October 2022 at the Anaiwoi Fish Market, Kolaka District. The method used is the interview and documentation method. Based on the results of the study, there were 31 species of demersal fish belonging to 12 families. The most dominant fish species were found from the Lutjanidae and Lethrinidae families. In general, the identification results of sustainable fisheries are quite good, such as fishing gear, types of environmentally friendly vessels, fishing locations and types of fish and size of fish caught. The type of boat most used by fishermen is the outboard motor. The most commonly used fishing gear is the fishing line.
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6

Zahara, Asha Aulia, Audya Septria Ningrum, Baiq Kharisma Afrilia Putri Zain, Ivonne Siswanty, and Selamet Kurniawan Riandinata. "Identifikasi Jenis Ikan Demersal dan Pengelolaan Perikanan Tangkap Berkelanjutan di Pasar Ikan Anaiwoi Kabupaten Kolaka." Journal of Marine Research 12, no. 3 (May 23, 2023): 422–30. http://dx.doi.org/10.14710/jmr.v12i3.37074.

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Анотація:
Perikanan tangkap adalah sumber daya yang dapat diakses secara terbuka atau milik bersama yang penggunaannya dapat mengalami penangkapan berlebih atau penangkapan ikan yang merusak jika ditangani tanpa menggunakan konsep yang ramah lingkungan dan berkelanjutan. Penelitian ini bertujuan untuk mengidentifikasi jenis ikan demersal hasil tangkapan nelayan dan mengetahui pengelolaan perikanan tangkap di perairan Desa Anaiwoi. Penelitian dilakukan pada bulan September hingga Oktober 2022 di Pasar Ikan Anaiwoi, Kabupaten Kolaka. Metode yang digunakan adalah metode wawancara dan dokumentasi. Berdasarkan hasil penelitian, terdapat 31 spesies ikan demersal yang termasuk dalam 12 famili. Jenis ikan yang paling dominan ditemukan dari famili Lutjanidae dan Lethrinidae. Secara umum hasil identifikasi perikanan berkelanjutan cukup baik, seperti alat tangkap, jenis kapal ramah lingkungan, lokasi penangkapan dan jenis ikan serta ukuran ikan yang ditangkap. Jenis perahu yang paling banyak digunakan nelayan adalah perahu motor tempel. Alat tangkap yang paling umum digunakan adalah tali pancing.Capture fisheries are openly accessible resources or common property whose use may experience overfishing or destructive fishing if handled without using environmentally friendly and sustainable concepts. This study aims to identify the species of demersal fish caught by fishermen and to determine the management of capture fisheries in the waters of Anaiwoi Village. The research was conducted from September to October 2022 at the Anaiwoi Fish Market, Kolaka District. The method used is the interview and documentation method. Based on the results of the study, there were 31 species of demersal fish belonging to 12 families. The most dominant fish species were found from the Lutjanidae and Lethrinidae families. In general, the identification results of sustainable fisheries are quite good, such as fishing gear, types of environmentally friendly vessels, fishing locations and types of fish and size of fish caught. The type of boat most used by fishermen is the outboard motor. The most commonly used fishing gear is the fishing line.
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7

Mason, James, A. W. Newton, D. W. McKay, and J. A. M. Kinnear. "Fisheries in the Orkney area." Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 87, no. 1-2 (1985): 65–81. http://dx.doi.org/10.1017/s0269727000004164.

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SynopsisFishing has long played an important part in the economy of Orkney. Local vessels are all small, and fish predominantly inshore for shellfish. Demersal and pelagic fish are abundant in the offshore waters around Orkney, but these exposed waters can be fished only by large vessels from more distant ports, so that few fish are landed in the islands.Gadoids, especially haddock, cod and whiting, form the bulk of the demersal fish caught at Orkney. Stocks of all three are giving cause for concern, with declining spawning stock biomass and reduced recruitment. With the coming of processing, more local landing of demersal fish might occur. The closure of the herring fishery in 1977 was followed by a great expansion of mackerel fishing, but with the lifting of the ban west of 4CW in 1981, herring catches have once again become valuable. Because of fishing pressure, landings of both species are subject to quota restrictions.In recent years, the traditional fisheries for lobsters and crabs have been supplemented by a new fishery for scallops. Lobster stocks are now under some pressure. Conditions around Orkney appear suited to farming filter-feeding bivalve molluscs, and culture and marketing of Pacific oysters has started.
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8

Howard, F. G., D. W. McKay, and A. W. Newton. "Fisheries of the Forth, Scotland." Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 93, no. 3-4 (1987): 479–94. http://dx.doi.org/10.1017/s0269727000006898.

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SynopsisHistorical aspects of the Firth of Forth fisheries are described, and the present state of the stocks of exploited species is reviewed. The once-substantial pelagic fisheries have declined and now constitute only a minor component of the firth fisheries. Herring fisheries were based on spring spawning herring but the herring now caught in the firth are from stocks of overwintering juveniles of autumn spawning herring. Recent conservation measures have closed many of the firth grounds to herring and sprat fishing. The main demersal species caught are cod, haddock, whiting, plaice and lemon sole. Most landings are from catches made in the middle and outer firths and the North Sea. The demersal pair trawl is now the most important gear used in directed demersal fishing. The most important shellfish fishery is that for the Norway lobster, current landings being valued at £2·4 million. Over-exploitation resulted in a decline in the stocks in the late 1970s. They are now recovering. Recent studies suggest that population characteristics of Norway lobsters are influenced by the physical environment. The firth today is one of the most intensively exploited areas in Scotland for lobster and crabs. Other exploited shellfish include squid, winkles and mussels.
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9

Apriliani, Izza Mahdiana, Asep Agus Handaka Suryana, Ine Maulina, and Rizka Zahra Utami. "Social and cultural characteristics in the development of small-scale fisheries: Case study of Cangkol Village, Cirebon, Indonesia." International Journal of Multidisciplinary Research and Growth Evaluation 4, no. 4 (2023): 842–46. http://dx.doi.org/10.54660/.ijmrge.2023.4.4.842-846.

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An overview of the condition of capture fisheries in an area is a tool for regional management parties in maintaining the sustainability of fishery resources in it. This research is focused on describing in general the area and conditions of capture fisheries in Kampung Cangkol, Cirebon. Residents in the Cangkol Village area have livelihoods as fishermen as much as 0.9% of the population. Within 5 years (2018–2022), the number of fishermen in Cangkol Village has tended to decrease. Nonetheless, the trend in numbers and production value of the catch of Cangkol Village fishermen tend to increase with the catch of demersal fish by the characteristics of sandy and muddy waters.
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10

Borges, Lisa, Alain F. Zuur, Emer Rogan, and Rick Officer. "Modelling discard ogives from Irish demersal fisheries." ICES Journal of Marine Science 63, no. 6 (January 1, 2006): 1086–95. http://dx.doi.org/10.1016/j.icesjms.2006.03.017.

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Abstract Annual discard ogives were estimated using generalized additive models (GAMs) for four demersal fish species: whiting, haddock, megrim, and plaice. The analysis was based on data collected on board commercial vessels and at Irish fishing ports from 1995 to 2003. For all species the most important factors influencing annual discard ogives were fleet (combination of gear, fishing ground, and targeted species), mean length of the catch and year, and, for megrim, also minimum landing size. The length at which fish are discarded has increased since 2000 for haddock, whiting, and plaice. In contrast, discarded length has decreased for megrim, accompanying a reduction in minimum landing size in 2000.
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11

Longdong, Florence Verra, Edwin L. A. Ngangi, and Djuwita R.R. Aling. "Distribution Patterns and Consumer Preferences on Demersal Fish in North Minahasa District." International Journal of Forest, Animal And Fisheries Research 6, no. 5 (2022): 17–24. http://dx.doi.org/10.22161/ijfaf.6.5.3.

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North Minahasa Regency is an area of North Sulawesi Province, which has the potential for capture fisheries that is growing significantly with the demand for raw materials for marine products, both for the consumption needs of the people of North Sulawesi in general and specifically in North Minahasa Regency itself, one of the sub-districts in North Minahasa Regency. which is the center of demersal fish capture fisheries production is Kema District. The success of marketing fish catch production is based on a well-targeted and efficient distribution pattern. This is strongly supported by interests and preferences, giving rise to a choice (preference) which one is desired. Culinary tourism in this area began to develop by showing an increasing trend. The number of restaurants or restaurants that offer grilled fish or seafood products has shown people's interest in fish consumption. The current high level of public interest in consuming fish automatically brightens the fisheries sector from upstream to downstream. The purpose of this study was to identify the marketing distribution pattern of demersal fish in North Minahasa Regency and analyze the attitudes of end consumers towards their preferences for demersal fish in North Minahasa Regency. The basic method in this research is a case study and the primary data source comes from fishermen and collectors as fish marketers, who are involved in marketing channels as well as final consumers who use the product. Respondents who are determined are producers, namely fishermen who catch Demersal fish, collectors or suppliers and final consumers in culinary centers who choose processed demersal fish products. Methods Data collection was carried out by sampling, namely: Purposive sampling for the types of producer and collector respondents, Accidental sampling for final consumers who apply their preferences to processed Demersal fish products in culinary centers located in North Minahasa district. Collecting data through interviews and direct observation as well as filling out a list of questions guided by the researcher. Primary and secondary data types, for primary data were analyzed descriptively qualitatively and descriptively quantitatively using data analysis techniques according to consumer attitude preferences. to the final consumer. The validity test was carried out on the snapper, chair, bobara, grouper, and escape variables, it was found that all the calculated r values were greater than r table, which means that all indicators in the questionnaire were declared valid with a moderately correlated to high category. The reliability test on snapper was 0.626, which means high reliability value, as well as for chariot fish the value was 0.669 , 0.721 passed and Goropa 0.600 which was categorized as sufficient for 5% and 1% error levels.
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12

Mardyani, Yeyen, Tahmat Kurnia, and Luky Adrianto. "PENGELOLAAN PERIKANAN SKALA KECIL DI PERAIRAN PESISIR KABUPATEN BANGKA DENGAN PENDEKATAN BIOEKONOMI." Jurnal Kebijakan Sosial Ekonomi Kelautan dan Perikanan 10, no. 2 (December 29, 2020): 91. http://dx.doi.org/10.15578/jksekp.v10i2.9305.

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Pengelolaan perikanan skala kecil di Kabupaten Bangka pada beberapa kurun waktu terakhir menunjukkan produktivitas yang semakin menurun. Hal ini disebabkan oleh pengelolaan ruang laut yang tidak hanya dimanfaatkan sebagai daerah penangkapan ikan, tetapi juga sebagai wilayah eksploitasi penambangan laut. Penelitian ini bertujuan untuk mengetahui status pemanfaatan perikanan skala kecil di perairan Kabupaten Bangka. Penelitian dilakukan dengan menggunakan data primer dan sekunder; analisis bioekonomi digunakan pada ketiga zona daerah penangkapan ikan (DPI) dengan memisahkan sumberdaya ikan pelagis dan demersal untuk melihat status pemanfaatan perikanan pada masing-masing zona. Ketiga zona daerah penangkapan ikan didasarkan pada kondisi eksisting menurut RZWP3K Provinsi Kepulauan Bangka Belitung, yaitu: Zona A (DPI dengan IUP), Zona A1 (DPI dengan IUP tanpa kegiatan), dan Zona B (DPI tanpa IUP). Hasil penelitian menunjukkan bahwa perikanan pelagis Zona A cenderung economical overfishing; sedangkan perikanan demersal sudah menunjukkan kondisi economical overfishing; Zona A1 berada pada kondisi underfishing; serta Zona B berada pada kondisi underfishing. Pemanfaatan perikanan Zona A dan A1 tidak mencapai 50% TAC; sedangkan pada Zona B hanya 15% TAC. Agar pemanfaatan perikanan baik pelagis ataupun demersal dapat berkelanjutan baik secara ekologi maupun ekonomi, pengelolaan perikanan skala kecil di perairan Kabupaten Bangka perlu dilakukan pengelolaan input pada upaya tangkap yang berbeda-beda pada tiap zona serta pengelolaan ekologi dan ekosistem.Title: Management of Small-Scale Fisheries in The Coastal Waters of Bangka Regency with Bioeconomic ApproachManagement of small-scale fisheries in Bangka Regency has recently shown decreased productivity. This is caused by the management of marine area which is not only used as a fishing ground, but also as an area of exploitation for off-shore mining. Based on these conditions, this study aims to determine the level of utilization of small-scale fisheries in the waters of Bangka Regency. This research uses primary and secondary data; bio-economic analysis was carried out in the three fishing ground zones by separating pelagic and demersal fish resources to see the utilization status of each zone. The three fishing ground zones are based on the existing fishing ground conditions according to RZWP3K Bangka Belitung Islands Province, namely: Zone A (fishing ground with IUP), Zone A1 (fishing ground with IUP without activities), and Zone B (fishing ground without IUP). The results showed that Pelagic Zone A fisheries tend to be economical, whereas demersal fisheries have shown economical overfishing; Zone A1 is under fishing; Zone B is under fishing. The utilization of fisheries in Zone A and A1 does not reach 50% TAC, while in Zone B it is only 15% TAC. For the utilization of pelagic and demersal fisheries to be sustainable both ecologically and economically, the management of small-scale fisheries in Bangka Regency waters needs to carry out input management for different fishing efforts in each zone as well as ecological and ecosystem management.
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13

Reniban, Lidya Elsye. "Sistem Informasi Inventarisasi Sumberdaya Perikanan Kabupaten Maluku Tenggara Dengan Metode Rapid Application Development Berbasis Web." Jurnal Teknik Komputer 5, no. 2 (August 1, 2019): 241–48. http://dx.doi.org/10.31294/jtk.v5i2.5463.

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- Southeast Moluccas Regency is a districts in Moluccas Province that is rich in marine fisheries resources, especially pelagic fish, seaweed, and demersal fish. Knowledge of information fisheries resources by fishermen and the community in general in the regions is still low, because the unavailability of easy information media to access information about fisheries resources in this area. The research aims to design an information system of fisheries resources inventory to improve the performance of the Southeast Moluccas Regency Government to inform and process data on fisheries resources. System design method uses RAD (Rapid Application Development). System design tools use UML (Unified Modeling Language), to make applications using the PHP(Hypertext Preprocessor) programming language, and MySQL as the database. Information System for Fisheries Resources has been tested using the blackbox method, the results show the system runs as expected. This system can display information on Southeast Moluccas Regency Fisheries Resources informally to the public and can be used as a tool for local governments to improve performance for presentation and processing of data and information in the marine and fisheries sector. Keywords: Information Systems,Inventory, Fisheries, RAD, UML
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Caddy, J. F. "OPTIONS FOR THE REGULATION OF MEDITERRANEAN DEMERSAL FISHERIES." Natural Resource Modeling 4, no. 4 (September 1990): 427–75. http://dx.doi.org/10.1111/j.1939-7445.1990.tb00219.x.

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15

van der Reijden, Karin J., Niels T. Hintzen, Laura L. Govers, Adriaan D. Rijnsdorp, and Han Olff. "North Sea demersal fisheries prefer specific benthic habitats." PLOS ONE 13, no. 12 (December 18, 2018): e0208338. http://dx.doi.org/10.1371/journal.pone.0208338.

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16

Engås, A. "A species-selective trawl for demersal gadoid fisheries." ICES Journal of Marine Science 55, no. 5 (October 1998): 835–45. http://dx.doi.org/10.1006/jmsc.1998.0352.

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17

Farriols, M. Teresa, Francesc Ordines, Pierluigi Carbonara, Loredana Casciaro, Manfredi Di Lorenzo, Antonio Esteban, Cristina Follesa, et al. "Spatio-temporal trends in diversity of demersal fish assemblages in the Mediterranean." Scientia Marina 83, S1 (January 9, 2020): 189. http://dx.doi.org/10.3989/scimar.04977.13a.

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The high species richness, coupled with high proportion of endemism, makes the Mediterranean one of the world’s ‘biodiversity hotspots’. However, the continuous increase in fisheries in the last few decades has led to the overexploitation of their main commercial stocks. Using fishery-independent data collected under the framework of the MEDITS trawl surveys carried out over the last 20 years, we study the demersal fish diversity pattern in the Mediterranean at a large spatial and temporal scale to determine whether it is being affected by the general fishing overexploitation of the demersal resources. The detected diversity trends are compared with the spatio-temporal variation in bottom trawl fishing effort in the Mediterranean. Our results show a stability and even recovery of demersal fish diversity in the Mediterranean together with higher diversity values on the continental shelves of the Balearic Islands, Sardinia, Sicily and the Aegean Sea. At large temporal and spatial scales, the high diversity of demersal assemblages in the Mediterranean is associated with a reduction in bottom trawl fishing effort. The inclusion of species other than target ones through diversity indices is important in the implementation of an ecosystem-based fisheries management.
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18

Werner, Timothy B., Simon Northridge, Kate McClellan Press, and Nina Young. "Mitigating bycatch and depredation of marine mammals in longline fisheries." ICES Journal of Marine Science 72, no. 5 (May 2015): 1576–86. http://dx.doi.org/10.1093/icesjms/fsv092.

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Abstract Demersal and pelagic longline fisheries involve frequent and geographically widespread interactions with many individuals, populations, and species of marine mammals. Animals sometimes suffer mortality and serious injury following these interactions, attracted mainly to longlines as a source of food. This depredating behaviour can have serious consequences for fishermen, especially when they lose valuable catch and face other associated operational and regulatory challenges. Using input from a group of international experts in the science, fishing industry, and government sectors, we produced a list of methods for mitigating depredation and bycatch of marine mammals in longline fisheries, collectively assessed their potential as a solution, and determined priorities for further research. The intention of this review is to help synthesize our current understanding about potential solutions, to provide an introduction to the articles that appear in this themed set of the ICES Journal of Marine Science, and to help fishermen, fisheries managers, and research scientists advance solutions to this global problem.
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19

Yahya, Reza, Arif Mahdiana, and Muslih Muslih. "Status Perikanan Tangkap di Kabupaten Kebumen." MAIYAH 2, no. 2 (June 1, 2023): 60. http://dx.doi.org/10.20884/1.maiyah.2023.2.2.8524.

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Capture fisheries in Kebumen Regency has a large potential of fish resources. The status of capture fisheries in Kebumen Regency includes the development of the number of fishermen/RTPs, fishing vessels, fishing gear, fishing production volume, fishery production value, types and catches of fish. The results showed that Kebumen fishermen are included in the category of small fishermen based on the use of boat types less than 5 GT and outboard motorboats. The number of growth of fishermen and the number of fishing boats in Kebumen Regency increased throughout 2016-2020. Types of fishing gear used by fishermen in Kebumen district include fixed gill nets, drift gill nets, trammel nets, fishing rods and hooks. The production volume and production value of the Kebumen capture fishery decreased in 2020 due to the COVID-19 pandemic. Potential species caught by Kebumen fishermen were demersal fish with high economic value such as white pomfret (Pampus argenteus), lobster (Panulirus homarus), jerebung shrimp (Penaeus merguiensis) and red snapper (Lutjanus campechanus).
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ellis, j. r., n. k. dulvy, s. jennings, m. parker-humphreys, and s. i. rogers. "assessing the status of demersal elasmobranchs in uk waters: a review." Journal of the Marine Biological Association of the United Kingdom 85, no. 5 (October 2005): 1025–47. http://dx.doi.org/10.1017/s0025315405012099.

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elasmobranch fish are susceptible to over-exploitation by commercial and recreational fisheries and an increasing focus of conservation initiatives. the lack of accurate species-specific landings data in many european fisheries and the paucity of biological data have restricted the types of stock assessment that can be undertaken. hence, other methods of determining the overall status of elasmobranch fish are required. for demersal elasmobranchs around the british isles, the most widely available biological data describe life histories and abundance from fishery-independent surveys. here, we examine the length-distribution of demersal elasmobranchs caught during groundfish surveys, to determine which life history stages are sampled effectively. for these stages, we report trends in abundance and relate the trends to knowledge of the species' biology and fisheries, and to the decline criteria that are used to assess species' status by nature conservation agencies. the analyses show that many large demersal elasmobranchs have been severely depleted in uk waters but that groundfish surveys still provide a good source of data for monitoring changes in status of the more abundant species. for rare and highly depleted species, groundfish surveys often provide good retrospective descriptions of declines, but the surveys have limited power to detect recent changes in status.
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21

Ulrich, Clara, Youen Vermard, Paul J. Dolder, Thomas Brunel, Ernesto Jardim, Steven J. Holmes, Alexander Kempf, Lars O. Mortensen, Jan-Jaap Poos, and Anna Rindorf. "Achieving maximum sustainable yield in mixed fisheries: a management approach for the North Sea demersal fisheries." ICES Journal of Marine Science 74, no. 2 (August 6, 2016): 566–75. http://dx.doi.org/10.1093/icesjms/fsw126.

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Achieving single species maximum sustainable yield (MSY) in complex and dynamic fisheries targeting multiple species (mixed fisheries) is challenging because achieving the objective for one species may mean missing the objective for another. The North Sea mixed fisheries are a representative example of an issue that is generic across most demersal fisheries worldwide, with the diversity of species and fisheries inducing numerous biological and technical interactions. Building on a rich knowledge base for the understanding and quantification of these interactions, new approaches have emerged. Recent paths towards operationalizing MSY at the regional scale have suggested the expansion of the concept into a desirable area of “pretty good yield”, implemented through a range around FMSY that would allow for more flexibility in management targets. This article investigates the potential of FMSY ranges to combine long-term single-stock targets with flexible, short-term, mixed-fisheries management requirements applied to the main North Sea demersal stocks. It is shown that sustained fishing at the upper bound of the range may lead to unacceptable risks when technical interactions occur. An objective method is suggested that provides an optimal set of fishing mortality within the range, minimizing the risk of total allowable catch mismatches among stocks captured within mixed fisheries, and addressing explicitly the trade-offs between the most and least productive stocks.
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22

Fahmi, Fahmi, Mohammad Adrim, and Dharmadi Dharmadi. "SIZE AT FIRST MATURITY OF THE BLUE SPOTTED MASKRAY, Neotrygon kuhli lN INDONESIAN, WATERS." Indonesian Fisheries Research Journal 15, no. 2 (May 24, 2017): 29. http://dx.doi.org/10.15578/ifrj.15.2.2009.29-35.

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23

Ulrich, Clara, Stuart A. Reeves, Youen Vermard, Steven J. Holmes, and Willy Vanhee. "Reconciling single-species TACs in the North Sea demersal fisheries using the Fcube mixed-fisheries advice framework." ICES Journal of Marine Science 68, no. 7 (May 9, 2011): 1535–47. http://dx.doi.org/10.1093/icesjms/fsr060.

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Abstract Ulrich, C., Reeves, S. A., Vermard, Y., Holmes, S. J., and Vanhee, W. 2011. Reconciling single-species TACs in the North Sea demersal fisheries using the Fcube mixed-fisheries advice framework. – ICES Journal of Marine Science, 68: 1535–1547. Single-species management is a cause of discarding in mixed fisheries, because individual management objectives may not be consistent with each other and the species are caught simultaneously in relatively unselective fishing operations. As such, the total allowable catch (TAC) of one species may be exhausted before the TAC of another, leading to catches of valuable fish that cannot be landed legally. This important issue is, however, usually not quantified and not accounted for in traditional management advice. A simple approach using traditional catch and effort information was developed, estimating catch potentials for distinct fleets (groups of vessels) and métiers (type of activity), and hence quantifying the risks of over- and underquota utilization for the various stocks. This method, named Fcube (Fleet and Fisheries Forecast), was applied successfully to international demersal fisheries in the North Sea and shaped into the advice framework. The substantial overquota catches of North Sea cod likely under the current fisheries regimes are quantified, and it is estimated that the single-species management targets for North Sea cod cannot be achieved unless substantial reductions in TACs of all other stocks and corresponding effort reductions are applied.
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24

Oktaviyani, Selvia, Mennofatria Boer, and Yonvitner. "ANALISIS DEGRADASI DAN DEPRESIASI SUMBERDAYA IKAN DEMERSAL PADA PERIKANAN DOGOL DI PERAIRAN SELAT SUNDA (Degradation and Depreciation Analysis of Demersal Fish Resources on Dogol Fisheries in Sunda Strait)." Marine Fisheries : Journal of Marine Fisheries Technology and Management 6, no. 2 (October 7, 2016): 119. http://dx.doi.org/10.29244/jmf.6.2.119-128.

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ABSTRACT<br /><br />Dogol is one type of fishing gear which is operated by fisherman in Sunda Strait with demersal fishes as dominant catches, such as goatfish, threadfin brean, ponyfish, Indian halibut and drums.The utilization was done throughout the year and without control can lead to overfishing. The aim of this research is to estimate degradation and the depreciation rate of demersal fish resources of dogol fisheries in Sunda Strait. This research was conducted on February until July 2014 in Coastal Fishing Port (PPP) Labuan, Pandeglang, Banten. Data was collected through interview and questionnaire methods to dogol fisherman and other stakeholders, as well as time series data from Ministry of Marine Affairs Pandeglang district. The results showed that the average value of degradation and depreciation rate of demersal fish resources were 0,26-0,42 and 0,26-0,43 respectively. Those values still below 0,5, it means that demersal fish resources on dogol fisheries in Sunda Strait has not been degraded and depreciation. But, the CPUE values tended to decrease, so was needed preventive action, such as restriction of fishing effort and increase the mesh size to preserve the sustainability of demersal fish resources.<br /><br />Keywords: Degradation, demersal fish, depreciation, dogol, Sunda Strait<br /><br />ABSTRAK<br /><br />Dogol merupakan salah satu jenis alat tangkap yang dioperasikan oleh nelayan di Perairan Selat Sunda dengan hasil tangkapan dominan yaitu ikan demersal seperti ikan biji nangka, kurisi, peperek, sebelah dan tigawaja. Kegiatan pemanfaatan yang dilakukan sepanjang tahun dengan tidak adanya pengontrolan dapat mengakibatkan tangkap lebih. Tujuan penelitian ini adalah untuk mengetahui laju degradasi dan laju depresiasi sumberdaya ikan demersal pada perikanan dogol di Perairan Selat Sunda. Penelitian dilaksanakan pada bulan Februari hingga Juli 2014 di Pelabuhan Perikanan Pantai (PPP) Labuan, Pandeglang, Banten. Pengumpulan data dilakukan melalui metode wawancara dan kuisioner terhadap nelayan dogol dan stakeholder lainnya serta data time series perikanan tangkap DKP Kabupaten Pandeglang. Hasil menunjukkan bahwa sumberdaya ikan demersal memiliki pola produksi yang berfluktuasi. Rata-rata nilai koefisien degradasi dan depresiasi sumberdaya ikan demersal adalah 0,26-0,42 dan 0,26-0,43 secara berurutan. Nilai-nilai tersebut masih dibawah 0,5, artinya sumberdaya ikan demersal pada perikanan dogol di Perairan Selat Sunda diduga belum mengalami degradasi dan depresiasi. Namun, nilai CPUE cenderung mengalami penurunan, sehingga diperlukan tindakan preventif seperti pembatasan upaya tangkap dan peningkatan ukuran mata jaring untuk menjaga kelestarian sumberdaya ikan demersal.<br /><br />Kata kunci: Degradasi, ikan demersal, depresiasi, dogol, Selat Sunda
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Zimmermann, Fabian, and Mikko Heino. "Is size-dependent pricing prevalent in fisheries? The case of Norwegian demersal and pelagic fisheries." ICES Journal of Marine Science 70, no. 7 (August 24, 2013): 1389–95. http://dx.doi.org/10.1093/icesjms/fst121.

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Abstract Zimmermann, F., and Heino, M. 2013. Is size-dependent pricing prevalent in fisheries? The case of Norwegian demersal and pelagic fisheries. – ICES Journal of Marine Science, 70: . It is commonly acknowledged that body weight of fish is a key factor in determining market value of landed catch, thus influencing optimal harvest strategies. However, in management strategy evaluations and bioeconomic modelling, body size is often an overlooked economic parameter, and there are no systematic studies on the prevalence of size-dependent pricing. Here we assess the presence and magnitude of size-dependent pricing in ex-vessel prices of fish in Norwegian fisheries. The data encompass landings of four pelagic and four demersal stocks in Norway in 2000–2010. Linear mixed models and generalized additive models were used to determine the dependence of unit price on weight class as well as on total yield and time (year). The results show a significant positive relationship between weight class and price for seven out of the eight examined fish stocks. The relative effect of body weight on price was the strongest for cod, Greenland halibut, Norwegian spring-spawning herring and mackerel, lesser for North Sea herring and saithe, and negligible for horse mackerel. These findings demonstrate that size-dependent pricing is common in Norwegian fisheries, and is therefore of high relevance for resource economics and fisheries management.
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Sari, Yesi Dewita, Yusman Syaukat, Tridoyo Kusumastanto, and Sri Hartoyo. "PENGELOLAAN PERIKANAN DEMERSAL DI LAUT ARAFURA: PENDEKATAN BIOEKONOMI." Jurnal Sosial Ekonomi Kelautan dan Perikanan 13, no. 1 (November 1, 2018): 43. http://dx.doi.org/10.15578/jsekp.v13i1.6858.

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ABSTRAKLaut Arafura merupakan salah satu perairan yang penting, sebesar 21% potensi ikan Indonesia terdapat di perairan Arafura yaitu 2,64 juta ton per tahun. Pemanfaatan sumber daya ikan demersal terutama udang di Laut Arafura telah dilakukan semenjak tahun 1970an oleh perusahaan dengan sistem joint venture. Penelitian ini bertujuan untuk mengetahui tingkat optimal pengelolaan sumber daya ikan demersal di Laut Arafura dan perubahan rente ekonomi setelah adanya kebijakan moratorium kapal asing di Indonesia yaitu pelarangan penggunaan kapal pukat dan kapal asing. Penelitian ini menggunakan data sekunder runtun waktu yang bersumber dari Kementerian Kelautan dan Perikanan, Badan PusatStatistik serta hasil-hasil penelitian yang relevan. Metode analisis data menggunakan model bioekonomi perikanan dengan model surplus produksi Walters dan Hilborn. Analisis kebijakan ekonomi meliputijumlah alat tangkap, jumlah investasi dan rente ekonomi maksimum. Jumlah produksi tertinggi terjadi ketika pengelolaan pada kondisi maksimum secara biologi; sedangkan jumlah alat tangkap tertinggiyang diperbolehkan ketika pengelolaan pada kondisi open akses menggunakan alat tangkap pancing rawai dasar, serta rente ekonomi tertinggi diperoleh ketika pengelolaan pada kondisi maksimum secara ekonomi menggunakan pancing rawai dasar. Kebijakan pemerintah terkait moratorium kapal perikanan asing, memberikan kesempatan lebih banyak untuk kapal perikanan Indonesia dalam melakukanpenangkapan ikan demersal di WPP 718. Jumlah kapal perikanan dengan menggunakan alat tangkap pancing rawai dasar dapat dikembangkan sampai 4 ribuan unit untuk memanfaatkan ikan demersal yangoptimal secara ekonomi, sehingga rente ekonomi maksimum dapat diperoleh sebesar 3,40 trilyun rupiah per tahun.Title: Management of Demersal Fishery in the Arafura Sea: A Bio-Economic ApproachABSTRACT Arafura sea is one of important fishing ground in Indonesia, contributing 21% of fisheries at about 2,64 million ton/year. Arafura’s demersal fishery has been exploited since 1970 by joint venture system. This study aims to determine the optimum level of demersal fish management in Arafura Sea as well as the fluctuations of economic rent after the foreign fishing vessel moratorium in Indonesia. The studycollected time series data from 2001-2014 from Ministry of Marine and Fisheries, Statistics Indonesia and relevant researches. The data were analyzed using bioeconomic model, particularly Walters and Hilborn Model. Analysis of economic policy includes fishing gears, investments and maximum economic rents. The results show that the maximum production occurs when fisheries management is on maximum yield. The highest number of permitted fishing gear is reached when the management is on open access condition using the set longline, while the maximum economic rents are obtained when the managementis on maximum economic yield using the set long line. Foreign fishing vessel moratorium gives more opportunity to Indonesian vessels to catch more demersal fish in WPP 718. The number of total optimum fishing vessel could be increased up to 4 thousand units in WPP 718 for demersal fishery in order reach optimum economic rent of 3.40 trillion rupiah per year.
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27

Meekan, Mark G., Conrad W. Speed, Robert D. McCauley, Rebecca Fisher, Matthew J. Birt, Leanne M. Currey-Randall, Jayson M. Semmens, et al. "A large-scale experiment finds no evidence that a seismic survey impacts a demersal fish fauna." Proceedings of the National Academy of Sciences 118, no. 30 (July 19, 2021): e2100869118. http://dx.doi.org/10.1073/pnas.2100869118.

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Seismic surveys are used to locate oil and gas reserves below the seabed and can be a major source of noise in marine environments. Their effects on commercial fisheries are a subject of debate, with experimental studies often producing results that are difficult to interpret. We overcame these issues in a large-scale experiment that quantified the impacts of exposure to a commercial seismic source on an assemblage of tropical demersal fishes targeted by commercial fisheries on the North West Shelf of Western Australia. We show that there were no short-term (days) or long-term (months) effects of exposure on the composition, abundance, size structure, behavior, or movement of this fauna. These multiple lines of evidence suggest that seismic surveys have little impact on demersal fishes in this environment.
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Sánchez Lizaso, José Luis, Ivan Sola, Elena Guijarro-García, José Maria Bellido, and Ramón Franquesa. "A new management framework for western Mediterranean demersal fisheries." Marine Policy 112 (February 2020): 103772. http://dx.doi.org/10.1016/j.marpol.2019.103772.

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Palder, O. Jonas, Jordan P. Feekings, Shaun Fraser, and Valentina Melli. "Approaching single-species exclusion in mixed demersal trawl fisheries." Ocean & Coastal Management 242 (August 2023): 106672. http://dx.doi.org/10.1016/j.ocecoaman.2023.106672.

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Mackinson, Steven, Barrie Deas, Doug Beveridge, and John Casey. "Mixed-fishery or ecosystem conundrum? Multispecies considerations inform thinking on long-term management of North Sea demersal stocks." Canadian Journal of Fisheries and Aquatic Sciences 66, no. 7 (July 2009): 1107–29. http://dx.doi.org/10.1139/f09-057.

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Signatories of the 2002 World Summit on Sustainable Development declaration committed to maintain or restore fish stocks to levels that can produce the maximum sustainable yield (MSY), a goal that has been challenged on a number of grounds. The European Commission has stated an objective to manage fisheries (independently) to achieve MSY by 2015, which has catalysed the Regional Advisory Councils’ (RACs) thinking on MSY and how it relates to their goal of developing long-term management plans. This study uses an ecosystem model of the North Sea to investigate questions relating to MSY in the context of mixed demersal fisheries for cod, haddock, and whiting. Results suggest that it is not possible to simultaneously achieve yields corresponding to MSYs predicted from single-species assessments and that the contradictory response of whiting is central to the trade-offs in yield and value for mixed demersal fisheries. Incompatibility between mixed-fishery and ecosystem-scale considerations exemplifies the difficult conceptual and practical challenges faced when moving toward an ecosystem approach.
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Arroyo, Nina-Larissa, Georges Safi, Pauline Vouriot, Lucía López-López, Nathalie Niquil, Francois Le Loc’h, Tarek Hattab, and Izaskun Preciado. "Towards coherent GES assessments at sub-regional level: signs of fisheries expansion processes in the Bay of Biscay using an OSPAR food web indicator, the mean trophic level." ICES Journal of Marine Science 76, no. 6 (March 4, 2019): 1543–53. http://dx.doi.org/10.1093/icesjms/fsz023.

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Abstract Using the Bay of Biscay (BoB) as a case study, we conducted a transnational assessment of the mean trophic level (MTL, Ospar FW4) indicator at sub-regional level, over the last three decades. Our results confirm the apparent recovery of BoB’s bentho-demersal system, as shown by trends in the MTL indicator based on survey data. However, they also point at a concomitant “fishing through” process where the apparent stability revealed by the MTL indicator based on landed catch data may be masking the expansion of demersal fisheries to deeper waters, and an over-exploitation of resources (particularly abundant pelagic species). Moreover, they show how the combined examination of independent surveys and fishery landings allows the identification of ecological trends in ecosystem studies. In addition, our results confirm that analysing MTL at various threshold levels helps discerning the causality of trends in this indicator, especially if analyses for pelagic and demersal species are run independently. Further studies, at smaller (i.e. local) spatial scales, need to be conducted to ascertain our results and suggest appropriate management strategies aimed at regulating fisheries expansions in the area.
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Rossetto, Marisa, Isabella Bitetto, Maria Teresa Spedicato, Giuseppe Lembo, Monica Gambino, Paolo Accadia, and Paco Melià. "Multi-criteria decision-making for fisheries management: A case study of Mediterranean demersal fisheries." Marine Policy 53 (March 2015): 83–93. http://dx.doi.org/10.1016/j.marpol.2014.11.006.

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33

Punzón, Antonio, Lucia Rueda, Augusto Rodríguez-Basalo, Manuel Hidalgo, Pere Oliver, José Castro, Juan Gil, Antonio Esteban, Luis Gil de Sola, and Enric Massutí. "History of the Spanish demersal fishery in the Atlantic and Mediterranean Seas." ICES Journal of Marine Science 77, no. 2 (December 10, 2019): 553–66. http://dx.doi.org/10.1093/icesjms/fsz231.

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Abstract Long fisheries time series allow the review of baselines and inform our knowledge of past events that have conditioned the recent history of the stocks. In this study, we investigated trends in fisheries landings data for the most representative Atlantic and Mediterranean demersal fisheries off the Spanish Iberian Peninsula and the Balearic Islands (1933–1986). The aim was to analyse the evolution of demersal species exploitation and detect changes in landings and fishing tactics. Ten species were selected, which included teleosts, crustaceans, and cephalopods. Results indicated a decrease in Landings Per Unit of Capacity (LPUC) in six of the species examined. While in the Atlantic the process of substitution or incorporation of new species to the fisheries occurs progressively, in the Mediterranean this incorporation occurs simultaneously for many of the species. Four main fishing tactics (landing pattern obtained from the classification analysis of landings per species) were identified. Geographically nearby and connected regions developed similar fishing tactics to each other, and also changed over time. While the fleets from isolated regions were more specialized, and only carrying out one fishing tactic during the study period. Improvements in LPUC with the implementation of new technology and legislative and management measures were not observed.
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Sokolova, Maria, Adrià Mompó Alepuz, Fletcher Thompson, Patrizio Mariani, Roberto Galeazzi, and Ludvig Ahm Krag. "A Deep Learning Approach to Assist Sustainability of Demersal Trawling Operations." Sustainability 13, no. 22 (November 9, 2021): 12362. http://dx.doi.org/10.3390/su132212362.

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Bycatch in demersal trawl fisheries challenges their sustainability despite the implementation of the various gear technical regulations. A step towards extended control over the catch process can be established through a real-time catch monitoring tool that will allow fishers to react to unwanted catch compositions. In this study, for the first time in the commercial demersal trawl fishery sector, we introduce an automated catch description that leverages state-of-the-art region based convolutional neural network (Mask R-CNN) architecture and builds upon an in-trawl novel image acquisition system. The system is optimized for applications in Nephrops fishery and enables the classification and count of catch items during fishing operation. The detector robustness was improved with augmentation techniques applied during training on a custom high-resolution dataset obtained during extensive demersal trawling. The resulting algorithms were tested on video footage representing both the normal towing process and haul-back conditions. The algorithm obtained an F-score of 0.79. The resulting automated catch description was compared with the manual catch count showing low absolute error during towing. Current practices in demersal trawl fisheries are carried out without any indications of catch composition nor whether the catch enters the fishing gear. Hence, the proposed solution provides a substantial technical contribution to making this type of fishery more targeted, paving the way to further optimization of fishing activities aiming at increasing target catch while reducing unwanted bycatch.
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Hakim, Abdul, Endah Susanti, and Lisa Puspitasari. "Analysis of the Blue Economy Concept in Improving the Living Standards of Fishermen Through the Existence of Village-Owned Enterprises in Tanjung Batu Village, Berau District." DiE: Jurnal Ilmu Ekonomi dan Manajemen 14, no. 1 (March 28, 2023): 54–65. http://dx.doi.org/10.30996/die.v14i1.8329.

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Berau District has potential for demersal fisheries such as grouper, snapper and octopus. Demersal fish are fish that usually live in a demersal zone, such as the bottom of a sea or lake. This fish is an important economical fish in Berau City. However, with so many requests, fish supplies are depleting over time, so firm efforts are needed to bridge the supply and demand issues with sustainable and eco-friendly blue economy activities. The aims of this study are (1) to analyze the implementation of the blue economy in the fishing village of Tanjung Batu, Berau district. (2) To see the income level of traditional fishermen from going to sea in the village of Tanjung Batu, Berau Regency, (2) to find out the comparison of the income level of traditional fishermen with the existence of BUMdes in Tanjung Batu village, Berau Regency. The results of the study show that as a form of implementing blue economy activities, the Regional Government of Berau Regency is active in socializing fishermen with regulations so that fishermen also have a role in protecting fishery resources in their fishing activities. The Regional Government of Berau Regency also provides subsidies for environmentally friendly nets as a form of fishing gear revitalization aimed at protecting the ecosystem as a form of zero waste implementation in the blue economy. The existence of BUMDes in the Tanjung Batu fishing village in terms of providing business capital to fishermen, is able to provide positive results by increasing the catch of fishermen. Fishermen are able to increase their income in one catch while sailing. Fishermen can afford to buy modern tools to help when sailing, such as technological tools in the form of GPS and fish finders to make it easier to find fish. Keywords: Blue Economy, Coastal Fishermen, BUMDes
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36

Salgado, Enrique J., Stephanie E. Nehasil, and Peter J. Etnoyer. "Distribution of deep-water corals, sponges, and demersal fisheries landings in Southern California, USA: implications for conservation priorities." PeerJ 6 (October 10, 2018): e5697. http://dx.doi.org/10.7717/peerj.5697.

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Deep-sea corals in Southern California are diverse and abundant but subject to multiple stressors, including bottom-contact fisheries using mobile and fixed gear. There is a need for more information on the distribution of these taxa in relation to the distribution of demersal fishing effort, and the distribution of marine protected areas, in order to improve spatial planning. There are many marine managed areas in Southern California, including essential fish habitat (EFH) areas, conservation areas, and a national marine sanctuary, but specific areas of overlap between bottom fishing and benthic epifauna are poorly known. Groundfish surveys were conducted by the National Marine Fisheries Service using a remotely operated vehicle throughout Southern California between 2003 and 2011 to document abundance and distribution of deep-water rockfish and flatfish to a depth of 500 m. Corals and sponges were also common in these images, providing an opportunity to examine these communities. Analyses of 34,792 still images revealed abundance and diversity of coral and sponge taxa, as well as frequency of fishing debris. The occurrence data were overlaid in a geographic information system with landings data for deep-water (>50 m) demersal fisheries to identify areas of spatial overlap. Corals or sponges were observed in 23% of images. A total of 15 coral genera and six sponge morphotypes were identified. A total of 70 species codes were targeted by deep-water demersal fisheries operating below 50 m for years 2007–2011. A novel priority-setting algorithm was developed to identify areas of high richness, abundance, and fishing intensity (RAFi). Several highly-ranked areas were already protected as EFH (Footprint, Piggy Bank). Other highly-ranked sites (West Catalina Island, San Clemente Island, 9-Mile Bank, Santa Rosa Flats) were encompassed by transient gear restrictions, such as Rockfish conservation areas, but are now recommended for permanent protection by the Pacific Fishery Management Council.
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Pereira, Inês, Ualerson Iran Peixoto, Wendell Medeiros-Leal, Morgan Casal-Ribeiro, and Régis Santos. "Multidimensional Indicators to Assess the Sustainability of Demersal Small-Scale Fishery in the Azores." Sustainability 14, no. 24 (December 11, 2022): 16585. http://dx.doi.org/10.3390/su142416585.

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The Azorean demersal fishery sector is one of the most important in the archipelago. As a small-scale fishery, it plays an important role in the livelihood of the community, being a source of employment and income, and contributing to poverty alleviation. Because fisheries are a complex system, a multidisciplinary approach that includes socioeconomic indicators is required for a broader assessment of fishery sustainability. This study analyzes the Azorean bottom longline fishery using the Fishery Performance Indicators tool, regarding its ecology, economy, and community indicators. The findings indicated that the fishery is mostly sustainable, although there is still opportunity for improvement. Its ecological indicators had a good performance, mainly due to the effort and work of the scientific community that makes continuous studies to examine the state of its stocks. The economic indicators are in good condition as well, but some obstacles stopped the indicator from obtaining a better performance; mainly the landing volatility and the fishery’s main source of capital (subsidies), which can make the fishery less competitive. Finally, its community indicator had a very good performance, which reflects the fishery's socioeconomic and cultural relevance for the Azores.
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Mahulette, Ralph Thomas, and Andrias Samu Samu. "PENGUATAN KELEMBAGAAN UNTUK MENDUKUNG PENGELOLAAN SUMBER DAYA PERIKANAN LAUT ARAFURA." Jurnal Kebijakan Perikanan Indonesia 6, no. 2 (November 1, 2014): 87. http://dx.doi.org/10.15578/jkpi.6.2.2014.87-96.

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<p>Perairan Arafura yang berada di bagian Tenggara Maluku memiliki sumber daya perikanan laut demersal maupun udang dan jika dikelola dengan baik, mampu mendatangkan pendapatan bagi pemerintah pusat, daerah dan masyarakat pesisir. Pengelolan sumber daya udang dan ikan demersal sudah berlansung cukup lama di perairan Arafura dan status pemanfaatannya sudah berada dalam tahapan yang lebih tangkap (over-exploited). Kondisi yang demikian terjadi karena belum adanya pengelolaan yang tepat akibat kurangnya kualitas kebijakan dan informasi hasil penelitian untuk mendasari kebijakan tersebut. Makalah ini dimaksudkan untuk mengkaji strategi penguatan kelembagaan pengelolaan perikanan di lokal. Data sekunder dan observasi lapangan digunakan dalam kajian ini. Analisis data dilakukan secara diskriftif kualitatif. Hasil kajian mengindikasi bahwa dari sisi peraturan perundangan belum dijumpai adanya peraturan perundangan yang dibuat oleh pemerintah daerah yang mampu merespon isu dan permasalahan lokal. Oleh sebab itu strategis penguatan kelembagaan pengelolaan perikanan dirumuskan dalam kajian ini.</p><p> </p><p>Arafura waters are located in the Southeast Maluku sea, demersal fisheries resources as well as shrimp and if managed properly, able to bring in revenue for the central government, regional and coastal communities. Resource management of shrimp and demersal fish has been taking place for a long time in the waters of the Arafura and utilization status already in the stage of more catch (over-exploited). Such conditions occur due to lack of proper management due to lack of quality policies and information research results to the policy underlying. This paper is intended to examine the institutional strengthening of fisheries management strategies in local. Secondary data and field observations used in this study. Data analysis was done qualitatively diskriftif. results of the study indicate that the legislation has not encountered any regulations made by the local government that is able to respond to local issues and concerns. Therefore, institutional strengthening strategic management fisheries formulated in this study.</p>
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39

Dietrich, Kimberly S., Julia K. Parrish, and Edward F. Melvin. "Understanding and addressing seabird bycatch in Alaska demersal longline fisheries." Biological Conservation 142, no. 11 (November 2009): 2642–56. http://dx.doi.org/10.1016/j.biocon.2009.06.013.

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40

Suprapto, Suprapto. "INDEKS KEANEKARAGAMAN JENIS IKAN DEMERSAL DI PERAIRAN TARAKAN." BAWAL Widya Riset Perikanan Tangkap 6, no. 1 (December 31, 2015): 47. http://dx.doi.org/10.15578/bawal.6.1.2014.47-53.

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Perairan Tarakan termasuk daerah penangkapan sumber daya ikan demersal dan udang cukup potensial di KalimantanUtara. Tingginya tingkat eksploitasi ikan demersal dengan menggunakan trawlmenyebabkan keragaman jenisnya rendah. Penelitian ikan demersal dilakukan di perairan Tarakan pada bulanMei,Agustus dan Nopember 2012. Tujuan penelitian adalah untuk memperoleh indeks keanekaragaman jenis ikan demersal. Data spesies ikan demersal dikumpulkan dari hasil tangkapan jaring trawl yang dioperasikan oleh kapal motor 20GT dengan metode sapuan area. Hasil penelitian menunjukkan bahwa jumlah taksa ikan demersal sebanyak 86 spesies yang tergolong kedalam45 famili. Komposisi jenis hasil tangkapan trawl didominasi oleh famili Leiognathidae (ikan petek), Sciaenidae (ikan gulama), Harpadontidae (ikan nomei),Apogonidae (ikan serinding) danMullidae (ikan bijinangka). Status keanekaragaman jenis termasuk dalamkategori sedang dengan indeks “Shanon-Wiener” (H’)berkisar antara 1,7-2,5 sedangkan indeks kekayaan “Margalef” (R1 ) berkisar antara 7-8. Penyebaran spesies ikan demersal bersifat sedang dengan indeks kemerataan jenis (E) rata-rata sebesra 0,5.Kelimpahan ikan demersal tidak ada yang dominan, ditunjukkan oleh nilai indeks kemerataan jenis “Pielou” (E) rata-rata sebesar 0,4.Tarakan and adjacent waters is one of potentially fishing ground of demersal fish resources in north Kalimantan. High exploitation by trawler tend to decreased of biodiversity of demersal fish in this area. Research has been conducted in the waters of Tarakan duringMay, August and November 2012. The aim of this research is to get species diversity indices of demersal fish, which is expected to be useful as one of the data capacity for sustainable fisheries management policy. Data obtained by using trawl fishing gear with a sweept area method.The results showed that demersal fish species richness 86 species, belonging to 45 families. Dominant family are Leiognathidae, Sciaenidae, Harpadontidae, Apogonidae andMullidae. Result of analysis indicate that species diversity in Tarakan waters in the medium category. Status of biodiversity consist of: range value diversityindices “Shanon-Wiener” (H’) was 1.7 to 2.5; species richness indices of “Margalef” (R1 ) are between 7-8; evenness indices of “Pielou” (E 1) was 0,5 and dominant indices “Pielou” (E) an average of 0.4.
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41

Wijayanto, Donny Orlando, Akhmad Fauzi, and Luky Adrianto. "SURPLUS PRODUSEN PERIKANAN DEMERSAL DI PROVINSI JAWA BARAT DENGAN BERBAGAI NILAI DISCOUNT RATE." Jurnal Sosial Ekonomi Kelautan dan Perikanan 16, no. 2 (December 28, 2021): 153. http://dx.doi.org/10.15578/jsekp.v16i2.9593.

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Terdapat pandangan secara global mengenai status sebagai nelayan yang diidentikkan dengan kemiskinan, suatu pandangan yang sejalan dengan beberapa hasil penelitian di Indonesia. Produksi perikanan tangkap laut di Provinsi Jawa Barat relatif besar secara nasional. Produksi perikanan demersal berkontribusi sebesar 34,52% dari total produksi pada tahun 2017. Hasil produksi ini diperoleh dari aktivitas nelayan Provinsi Jawa Barat yang berada di WPP-712 dan di WPP-573. Tujuan pengelolaan perikanan, baik dari sisi ekonomi maupun dari sisi pemerintahan adalah untuk menyejahterakan pelaku usahanya. Indikator yang saat ini digunakan untuk mengukur kesejahteraan nelayan adalah Nilai Tukar Nelayan (NTN). Nilai tersebut untuk Provinsi Jawa Barat adalah 105,06 pada tahun 2014, dan 113,02 pada tahun 2017. Besaran tersebut menunjukkan bahwa secara keseluruhan nelayan di Provinsi Jawa Barat adalah sejahtera. Di sisi lain, konsep NTN tidak menunjukkan bahwa biaya yang dikeluarkan adalah biaya korbanan (opportunity cost), dan tidak mengakomodir konsep time value of money. Melihat kondisi ini maka pertanyaan yang ditimbulkan adalah apakah nelayan di Provinsi Jawa Barat masih sejahtera apabila dilihat melalui indikator lain selain NTN. Tujuan penelitian ini adalah menganalisis kesejahteraan nelayan perikanan demersal di Provinsi Jawa Barat menggunakan Surplus Produsen sebagai alat ukurnya. Hasil penelitian menunjukkan bahwa secara rata – rata, Surplus Produsen terbesar yang dialami nelayan yang berada di Laut Jawa adalah sebesar Rp3.897.109.483.225,20 pada discount rate 10%, dan nelayan di Samudra Hindia sebesar Rp104.452.115.805,11 pada discount rate 20%. Besaran discount rate tidak seiring dengan peningkatan Surplus Produsen. Perbandingan besaran Surplus Produsen dengan Angka Kemiskinan menunjukkan bahwa nelayan di Laut Jawa tidak dapat dikategorikan sebagai miskin, namun mereka yang berada di Samudra Hindia masih berada tepat di atas garis kemiskinan. Hal ini suatu hasil yang sedikit berbeda dibandingkan dengan angka NTN. Penelitian ini merekomendasikan penggunaan variabel Surplus Produsen sebagai komplemen bagi Nilai Tukar Nelayan sebagai ukuran kesejahteraan nelayan.Title: Producer Surplus Of Demersal Fisheries in West Java Province With Various Discount Rate ValuesThere is a global view of status as a fishers who is identified with poverty, a view that is in line with several research results in Indonesia. Marine capture fisheries production in West Java Province is nationally relatively large. Demersal fisheries production contributed 34.52% of total production in 2017. This production result was obtained from the activities of fishers in West Java Province of WPP-712 and in WPP-573. The purpose of fisheries management, both from an economic perspective and from a government perspective, is the welfare of business actors. The indicator currently used to measure fishers’s welfare is in terms of fishers term of trade index (NTN). The value for West Java Province was 105.06 in 2014, and 113.02 in 2017. This figure shows that overall fishers in West Java Province are prosperous. On the other hand, the NTN concept does not indicate that the costs incurred are opportunity costs, and does not accommodate the time value of money concept. Seeing this condition, the question raised is whether fishers in West Java Province are still prosperous when viewed through other indicators other than NTN. The purpose of this study was to analyze the welfare of demersal fishers in West Java Province using Producer Surplus as a measuring tool. Results show that on average, the largest producer surplus experienced by fishers in the Java Sea is Rp. 3,897,109,483,225.20 at a discount rate of 10%, and fishers in the Indian Ocean are Rp. 104,452.115,805.11 at a discount. 20% rate. The discount rate is not in line with the increase in Producer Surplus. Comparison of the Producer Surplus with the Poverty Figure shows that fishers in the Java Sea cannot be categorized as poor, but those in the Indian Ocean are still just above the poverty line. This is a slightly different result compared to the NTN figure. This study recommends the use of the Producer Surplus variable as a complement to the Fishers Exchange Rate as a measure of fishers’s welfare.
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42

Angin, Robet Perangin, NFN Sulistiono, Rahmat Kurnia, Achmad Fahrudin, and Ali Suman. "Struktur komunitas sumber daya ikan demersal berdasarkan kedalaman perairan di Laut Cina Selatan (WPP-NRI 711) [Community structure of demersal fish resources based on the depth of the waters in the South China Sea (Indonesia Fisheries Management Zone 711)]." Jurnal Iktiologi Indonesia 17, no. 1 (August 22, 2017): 67. http://dx.doi.org/10.32491/jii.v17i1.305.

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Information on distribution and community structure of demersal fish resources are important to be known as an input to the management of demersal fisheries. This study aimed to analyze the diversity and distribution of demersal fish resources based on the differences in the depth of the waters and the linkages to the environment. Research conducted in the South China Sea in May to June 2015 by operating a trawl gear in the station preset. The method of analysis of demersal fish diversity use some ecological indices i.e Margalef species richness index, Shannon-Wiener diversity index, Pielou evenness index, and Simpson dominance index. The ecological index value then associated with environmental conditions, using principal component analysis. Distribution of the ecological index indicated the stability of communities demersal fish resources getting better with the increase of depth. The most affected to the level of species richness and distribution of demersal fish were the parameters of depth, temperature and salinity, while the abundance distribution of fishes were associated with dissolved oxygen, and water transparency. The implication, that the water environmental conditions greatly affected the distribution and abundance of demersal fish. AbstrakInformasi mengenai persebaran dan struktur komunitas sumber daya ikan demersal penting sebagai bahan masukan untuk pengelolaan perikanan demersal. Penelitian ini bertujuan untuk menganalisis tingkat keanekaragaman dan persebaran sumber daya ikan demersal berdasarkan perbedaan kedalaman perairan, serta keterkaitannya dengan lingkungan. Penelitian dilaksanakan di Laut Cina Selatan pada bulan Mei sampai Juni 2015 dengan mengoperasikan alat tangkap pukat ikan di stasiun yang telah ditetapkan. Metode analisis keanekaragaman hayati ikan demersal menggunakan beberapa indeks ekologi yaitu indeks kekayaan jenis Margalef, indeks keanekaragaman Shannon-Wiener, indeks keseragaman Pielou, dan indeks dominansi Simpson. Nilai indeks ekologi tersebut kemudian dikaitkan dengan kondisi lingkungan, menggunakan analisis komponen utama. Hasil penelitian menunjukkan tingkat kestabilan komunitas sumber daya ikan demersal semakin baik seiring dengan meningkatnya kedalaman. Kedalaman, suhu, dan salinitas merupakan parameter yang paling memengaruhi tingkat kekayaan jenis serta persebaran sumber daya ikan demersal, sedangkan persebaran kelimpahan ikan sangat terkait dengan oksigen terlarut dan kecerahan perairan. Implikasinya, kondisi lingkungan perairan sangat memengaruhi persebaran dan kelimpahan ikan demersal.
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43

Kambey, Alex Denny, Nego E. Bataragoa, and Adnan S. Wantasen. "Study On Artificial Reef Made of Bamboo “Bambooreef” In Malalayang Dua Waters, Malalayang District, Manado." JURNAL ILMIAH PLATAX 5, no. 1 (January 19, 2017): 1. http://dx.doi.org/10.35800/jip.5.1.2017.14967.

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Building and placing artificial reef “Bambooreef” around the natural coral reef in Malalayang Dua is a modified concept to innovate the commonly present reef model and create a new alternative model. The technical approach on consideration was type/structure of raw material, difficulty of finding the raw material, artificial reef model formation. Results showed that Bambooreef could be used as growing site of coral transplants and other epiphytic organisms, such as algae, mollusk, and etc. The occurrence of demersal reef fishes around the “Bambooreef” reflected that the artificial reef was good enough to develop for coral rehabilitation program in the degraded areas. And as fish house. Based on the age of bambooreef placed for 8 months on the sea bottom, it was found that this material could stand long enough on the sea bottom. Further studies are needed in relation with the use of bambooreef as fish house to support the fisheries sustainability, particularly demersal reef fisheries, and as fish stock supplying ground to the surrounding waters. Keywords: Artificial reef, bambooreef, bamboo, demersal. Abstrak Pembuatan dan peletakan terumbu buatan dari bahan bambu “Bambooreef” di daerah sekitar terumbu karang perairan Malalayang Dua merupakan konsep modifikasi yang diterapkan untuk melakukan inovasi terhadap model terumbu karang yang sudah pernah ada dan menghasilkan model alternative baru. Pendekatan teknis yang akan dijadikan pertimbangan seperti; jenis/struktur bahan baku, tingkat kesulitan mendapatkan bahan baku, formasi modul terumbu buatan. Hasil menunjukkan bahwa penempatan Terumbu buatan “Bambooreef” di perairan Malalayang Dua dapat dijadikan tempat bertumbuhnya jenis-jenis transplan karang dan organisme penempel lainnya seperti jenis Alga dan moluska, dll. Kehadiran jenis–jenis ikan demersal karang sekitar “Bambooreef” menunjukkan bahwa terumbu buatan tersebut cukup baik untuk dikembangkan dalam rangka rehabilitasi karang di daerah yang telah mengalami degradasi, dan menjadi rumah ikan. Berdasarkan umur terumbu buatan dari bahan bambu yang diletakkan di dasar perairan 8 bulan, maka ditemukan bahwa bahan bambu tersebut akan dapat bertahan cukup lama di dasar perairan. Penelitian lanjutan mengenai bambooreef perlu dilakukan untuk memanfaatkan terumbu buatan dari bahan bambu sebagai rumah ikan dalam rangka menunjang kegiatan keberlajutan perikanan khususnya perikanan demersal karang, dan sebagai daerah penyedia stok ikan bagi perairan sekitarnya. Kata kunci: Terumbu buatan, bambooreef, bambu, demersal.
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44

Mikuš, Ornella, Magdalena Zrakić, Tihana Kovačićek, and Mateja Jež Rogelj. "Common Fisheries Policy and its impact on the fisheries sector in Croatia." Croatian Journal of Fisheries 76, no. 1 (March 1, 2018): 41–50. http://dx.doi.org/10.2478/cjf-2018-0005.

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Abstract The aim of the paper is: 1) to determine the key changes in the evolution process of the EU Common Fisheries Policy (CFP) and the Croatia’s fisheries policy and 2) to describe the structure and dynamics of macroeconomic and budget performance related to Croatian fisheries in the period 2007-2016. Two methods were used: the historical method and the descriptive analysis of macroeconomic performance and budget structure. The CFP was officially introduced in 1983, bringing the management of fisheries in all EU member states under one system. Its aims were: to resolve sea conflicts between member states, to provide stability to the fisheries sector, to prevent a total collapse of fish stocks and to provide higher quality of life to the fishermen. However, the CFP has constantly been criticized for poor enforcement of environmental measures and scientific recommendations, and for the lack of a common language between the EU institutions and local stakeholders. Both the European and Croatian fisheries sector faced many problems, especially during the transition period in the 1990s. Some of them included a serious decrease of catches, outdated technology and fisheries fleet, depletion of demersal species, lack of developmental trends in mariculture, absence of measures of rational exploitation and protection of economically significant species. The negotiation period was an opportunity for the fisheries sector in Croatia to adapt its goals, measures and stakeholders in order to achieve a more sustainable and internationally competitive fisheries sector in the future. The membership facilitates trade in the EU area, along with providing significant funding and technical assistance. The budget support structure and the existing policy framework point out an increase in the implementation of structural measures which should assist in an overall improvement of social, economic and environmental aspects of fisheries.
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45

Tubino, Magda Fernandes de Andrade, and Melquíades Pinto Paiva. "LENGTH-WEIGHT RELATIONSHIP OF MARINE COMMERCIAL FISH SPECIES IN RIO DE JANEIRO STATE, BRAZIL." Arquivos de Ciências do Mar 40, no. 2 (December 1, 2007): 92–95. http://dx.doi.org/10.32360/acmar.v40i2.6117.

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Length-weight relationship parameters of thirteen species of demersal and pelagic fishes that are of economic and ecological relevance in the commercial fisheries of Rio de Janeiro State, southeastern of Brazil, are presented. These relationships indicate a positive allometry tendency for the regression slope, b in the sampled fish community.
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46

Jablonski, Silvio, Alexandre de Freitas Azevedo, and Luiz Henrique Arantes Moreira. "Fisheries and conflicts in Guanabara Bay, Rio de Janeiro, Brazil." Brazilian Archives of Biology and Technology 49, no. 1 (January 2006): 79–91. http://dx.doi.org/10.1590/s1516-89132006000100010.

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Despite the magnitude of domestic and industrial pollution, fishery yield registered in several landing points at Guanabara Bay, between April 2001 and March 2002 was slightly over 19,000 tons, corresponding to a value of US$ 4.8 million. When considered only the fish directed to the food market, the total catch amounted to about 6,300 tons and a value of US$ 3.7 million. Only a few fish species reached expressive densities compatible with commercial fisheries. Among small pelagic fish, Atlantic anchoveta and Brazilian sardinella were the dominant species, while in terms of demersal fish, croakers, mullets and catfishes comprised the main part of the catch. The absence of landing data previous to the spilling of 1.3 million liters of oil in January 2000 led to claims by fishermen representative organizations of values corresponding to about 50 years of fish harvest in the bay. Possibly, a data collection network could be established in a participative way with the main fishermen local associations. The relatively stabilized fisheries in the bay suggested that reasonable inferences could be made, without, necessarily having a complete coverage of all landing points.
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47

Vu, Ha Viet, and Thi Van Dang. "THE USE OF SWEPT-AREA METHOD IN ESTIMATION OF DEMERSAL FISH STOCK BIOMASS IN VIETNAM." Science and Technology Development Journal 12, no. 3 (February 15, 2009): 103–11. http://dx.doi.org/10.32508/stdj.v12i3.2225.

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Demersal and semi-demersal fishes were the important species which contributed a relatively high ration in the total marine catches. Research on standing stock omass of fishes are now considered as an urgent need to give advices for fisheries planning management and sustainable use of the marine resources. However, the accuracy and precise estimate have limitations and need to be improved. There are a number of methods used to estimate the stock size of fishes, swept-area method using bottom trawlnet is one of the most popular approaches used in the world. This paper reviews the use of this method in estimation of fish stock size in Vietnam.
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48

Ba, Kamarel, Modou Thiaw, Massal Fall, Ndiaga Thiam, Beyah Meissa, Didier Jouffre, Omar Thiom Thiaw, and Didier Gascuel. "Long-term fishing impact on the Senegalese coastal demersal resources: diagnosing from stock assessment models." Aquatic Living Resources 31 (2018): 8. http://dx.doi.org/10.1051/alr/2017046.

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For the first time in Senegal, assessments based on both stochastic and deterministic production models were used to draw a global diagnosis of the fishing impact on coastal demersal stocks. Based one national fisheries databases and scientific trawl surveys data: (i) trends in landings since 1971 were examined, (ii) abundance indices of 10 stocks were estimated using linear models fitted to surveys data and commercial catch per unit efforts, and (iii) stock assessments were carried out using pseudo-equilibrium Fox and Pella-Tomlinson models and a Biomass dynamic production model fitted in a Bayesian framework to abundance indices. Most stocks have seen their abundance sharply declining over time. All stocks combined, results of stock assessments suggest a 63% reduction compared to virgin state. Three fifth of demersal stocks are overexploited and excess in fishing effort was estimated until 75% for the worst case. We conclude by suggesting that the fishing of such species must be regulated and an ecosystem approach to fisheries management should be implemented in order to monitor the whole ecosystem.
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49

Wardani, Firdha Iresta, N. Nadiarti, Alfa FP Nelwan, and Muhammad Jamal. "Vulnerability analysis of pelagic and demersal fisheries in the Indian Ocean, Fisheries Management Area 572, Indonesia." IOP Conference Series: Earth and Environmental Science 763, no. 1 (May 1, 2021): 012040. http://dx.doi.org/10.1088/1755-1315/763/1/012040.

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50

Dunning, M., S. McKinnon, CC Lu, J. Yeatman, and D. Cameron. "Demersal cephalopods of the Gulf of Carpentaria, Australia." Marine and Freshwater Research 45, no. 3 (1994): 351. http://dx.doi.org/10.1071/mf9940351.

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Demersal trawl and dredge surveys of the Gulf of Carpentaria in the early summers of 1990 and 1991 provided the first comprehensive assessment of the cephalopod fauna of this shallow, tropical basin off northern Australia. Twenty-one taxa (comprising five loliginid squids, seven cuttlefishes, seven octopuses and two dumpling squids) were recorded. In addition to hosting species distributed broadly in the Indo-West Pacific (e.g. loliginid squids Sepioteuthis lessoniana, Photololigo cf. chinensis and P. cf. edulis; cuttlefishes Sepia eiliptica and Sepia pharaonis), the Gulf of Carpentaria represents the most northwesterly extent of the range of some eastern Australian species (e.g. Loliolus noctiluca and Sepia whitieyana). Squid catches were lower in the north-western gulf in 1990 and higher in shallower water during the more geographically restricted survey in 1991, whereas cuttlefish were more evenly distributed throughout the different sampling areas in both years. Broad size ranges of both sexes of the four most abundant species (P. cf. chinensis (northern form), P. cf. eduiis, S. eiliptica and S. pharaonis) are indicative of extended spawning seasons, and fully mature individuals of these species were evident throughout the gulf. Cephalopods are a minor component in reported domestic fisheries catches from the Gulf of Carpentaria, where penaeid prawns are targeted. High (though seasonal) squid catch rates were reported annually by Taiwanese trawlers targeting butterfish and squid from certain areas prior to 1979. With the observed population structure of the abundant cephalopod species and relatively high catch rates in some localities during these recent surveys, it is suggested that the cephalopod resources of the Gulf of Carpentaria could support increased commercial fisheries exploitation.
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