scholarly journals Assessing Cephalopods Fisheries in the Strait of Sicily by Using Poor Data Modeling

2021 ◽  
Vol 8 ◽  
Author(s):  
Michele L. Geraci ◽  
Fabio Falsone ◽  
Vita Gancitano ◽  
Danilo Scannella ◽  
Fabio Fiorentino ◽  
...  
Keyword(s):  
Maximum Sustainable Yield ◽  
Life Cycles ◽  
Bottom Trawl ◽  
Production Model ◽  
Small Scale ◽  
Octopus Vulgaris ◽  
Economic Point ◽  
Surplus Production ◽  
Strait Of Sicily ◽  
The Mediterranean

Cephalopods, including octopuses, squids, and cuttlefishes, are exploited by both bottom trawl and small-scale fisheries (SSF) in most of the Mediterranean areas. Bottom trawl fisheries regard cephalopods as a valuable bycatch, whereas for SSF, they are among the main target species. Cephalopods account for a relatively small proportion of the total landings in the Mediterranean. However, from an economic point of view, four cephalopods, Eledone cirrhosa, Eledone moschata, Octopus vulgaris, and Sepia officinalis, account for approximately 15% of the total landing value. Despite their economic importance, there are very few stock assessments of cephalopods in the Mediterranean because it is difficult to assess them by classical age-based methods, given their short life-cycles, and highly variable growth and recruitment. The production of E. cirrhosa, E. moschata, Illex coindettii, Loligo vulgaris, O. vulgaris, S. officinalis, and Todaropsis eblanae in the waters off the south of Sicily accounts for approximately 8% of the total Mediterranean yield of cephalopods. This study presents the first attempt to assess the state of these cephalopods in the Strait of Sicily by using surplus production models. Since species-wise landing statistics may be unreliable because of their morphological similarity, some octopuses (E. cirrhosa and E. moschata) and ommastrephid squids (I. coindetii and T. eblanae) were assessed combined. Landing data and abundance indices from trawl surveys were used to describe cephalopod stock dynamics through the Bayesian State Space Schaefer model (BSM) and Surplus Production model in Continuous Time (SPiCT) models. As survey data were not considered reliable indicators of their abundance, O. vulgaris, S. officinalis, and L. vulgaris stocks were assessed using the Catch-Maximum Sustainable Yield (CMSY) model. Overall, squid and cuttlefish stocks were observed to be in healthy conditions. However, assessments of octopus stocks indicated that their condition was critical or recovering. Here, we discuss the different stock statuses in the light of evolving fisheries and environmental factors in the area over time. Although cephalopods are not a priority in the current management system of Mediterranean fisheries, the importance of these species in the food web and their relevance for SSF underline their importance and their exploitation status should be periodically evaluated.

On a saddled snake eel Pisodonophis semicinctus (Osteichthyes: Ophichthidae) trawled in the Strait of Sicily (Mediterranean Sea)

2000 ◽  
Vol 80 (5) ◽  
pp. 951-952 ◽  
Author(s):  
Sergio Ragonese ◽  
Giovan Battista Giusto
Keyword(s):  
Body Weight ◽  
Mediterranean Sea ◽  
Bottom Trawl ◽  
Northern Coast ◽  
Rare Finding ◽  
Strait Of Sicily ◽  
Total Length ◽  
The Mediterranean

The occurrence in the Strait of Sicily of the saddled snake eel, Pisodonophis semicinctus (Osteichthyes: Ophichthidae), a rare finding for the Mediterranean Sea, is confirmed on the basis of one specimen caught off the northern coast of Tunisia in 1991. The specimen, 800 mm in total length and 457 g in body weight (preserved condition), was captured during a commercial bottom trawl hauled at 30 m next to Cape Bon (north of Tunisia). This represents the second and fourth documented record of this Atlantic intruder within the Strait of Sicily and the Mediterranean Sea, respectively.

scholarly journals Fisheries Reference Point and Stock Status of Croaker Fishery (Sciaenidae) Exploited from the Bay of Bengal, Bangladesh

2022 ◽  
Vol 10 (1) ◽  
pp. 63
Author(s):  
Partho Protim Barman ◽  
Md. Mostafa Shamsuzzaman ◽  
Petra Schneider ◽  
Mohammad Mojibul Hoque Mozumder ◽  
Qun Liu
Keyword(s):  
Bay Of Bengal ◽  
Maximum Sustainable Yield ◽  
Reference Points ◽  
Production Model ◽  
Fishing Pressure ◽  
Surplus Production ◽  
Stock Status ◽  
Management Measures ◽  
Production Models ◽  
The Monte Carlo Method

This research evaluated fisheries reference points and stock status to assess the sustainability of the croaker fishery (Sciaenidae) from the Bay of Bengal (BoB), Bangladesh. Sixteen years (2001–2016) of catch-effort data were analyzed using two surplus production models (Schaefer and Fox), the Monte Carlo method (CMSY) and the Bayesian state-space Schaefer surplus production model (BSM) method. This research applies a Stock–Production Model Incorporating Covariates (ASPIC) software package to run the Schaefer and Fox model. The maximum sustainable yield (MSY) produced by all models ranged from 33,900 to 35,900 metric tons (mt), which is very close to last year’s catch (33,768 mt in 2016). The estimated B > BMSY and F < FMSY indicated the safe biomass and fishing status. The calculated F/FMSY was 0.89, 0.87, and 0.81, and B/BMSY was 1.05, 1.07, and 1.14 for Fox, Schaefer, and BSM, respectively, indicating the fully exploited status of croaker stock in the BoB, Bangladesh. The representation of the Kobe phase plot suggested that the exploitation of croaker stock started from the yellow (unsustainable) quadrant in 2001 and gradually moved to the green (sustainable) quadrant in 2016 because of the reduction in fishing efforts and safe fishing pressure after 2012. Thus, this research suggests that the current fishing pressure needs to be maintained so that the yearly catch does not exceed the MSY limit of croaker. Additionally, specific management measures should implement to guarantee croaker and other fisheries from the BoB.

scholarly journals Penentuan Status Pemanfaatan dan Pengelolaan Ikan Tongkol (Auxis rochei) yang Tertangkap di Perairan Bolaang-Mongondow Selatan dan Bolaang-Mongondow Timur Sulawesi Utara

d'CARTESIAN ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 1
Author(s):  
Ladi Beatriex Deeng ◽  
Hanny A H Komalig ◽  
John S Kekenusa
Keyword(s):  
Maximum Sustainable Yield ◽  
Production Model ◽  
Model Data ◽  
Biological Resource ◽  
Surplus Production ◽  
North Sulawesi ◽  
Surplus Production Model ◽  
The Status ◽  
Level Of Effort

LADI BEATRIEX DEENG. Determination of Utilization and Management Status of Bonito (Auxis Rochei) Caught in South Bolaang-Mongondow and East Bolaang-Mongondow Waters of North Sulawesi. Supervised by Mr. JOHN S. KEKENUSA as main supervisor, and Mr. HANNY A. H. KOMALIG as co-supervisor.Bonito (Auxis rochei), needs to be managed properly because even though it is a renewable biological resource, it can experience overfishing, depletion or extinction. One way to approach the management of fish resources is by modeling. The analysis was carried out aiming to determine the status of utilization and management of bonito and maximum sustainable yield (MSY) using the Surplus Production Model. Data on catching and efforts to catch bonito is collected from the Marine and Fisheries Service of South Bolaang-Mongondow Regency and East Bolaang-Mongondow of North Sulawesi. The surplus production model that can be used to determine the catch of bonito is the Schaefer model. The maximum sustainable catch of bonito is 869.556 tons per year, obtained at the level of catching effort of 933 trips. For 2017 the level of utilization is 64.95 % so that production can still be increased, with a level of effort of 73.74 % indicating the level of effort that is not optimal and can still be increased. Keywords : Bonito, Surplus Production Model, South Bolaang-Mongondow and   East Bolaang-Mongondow Regency

scholarly journals OVERFISHING AND OVERCAPACITY SMALL SCALE FISHERIES IN SEMARANG CITY

2019 ◽  
Vol 11 (2) ◽  
pp. 427-435
Author(s):  
Jamaludin Malik ◽  
Achmad Fahrudin ◽  
Dietriech Geoffrey Bengen ◽  
Taryono Khodiron
Keyword(s):  
Sustainable Management ◽  
Maximum Sustainable Yield ◽  
Utilization Rate ◽  
Small Scale ◽  
Fishing Gear ◽  
Catch Per Unit Effort ◽  
Small Scale Fisheries ◽  
Surplus Production ◽  
Capacity Level ◽  
The Status

Fisheries in Semarang City are dominated by small-scale fisheries. This is indicated by the use of the largest fishing fleet of 10 gross tons operating near the coast. This study aims to analyze the status of small-scale fisheries in Semarang City for sustainable management. Sustainable management is management that guarantees the availability of natural resources and environmental services for future generations. The study was conducted for three months, namely September-November 2018 in the coastal waters of Semarang City, which was part of the Fisheries Management Region (WPP) 712. The method used in this study is the analysis of time series surplus production, namely data from the catch (ton/year) and the number of fishing gear (unit) within 10 years (2007-2016), to calculate the catch per-unit effort (CPUE), maximum sustainable yield (MSY), optimum effort (fopt), utilization rate (TP) and capacity level (TK). This study was obtained results of a downward trend in CPUE; the existing fishery catch or production in 2016 has exceeded the MSY value is 479 tons/year (Schaefer) and 439.11 tons/year (Fox); utilization rate of more than 100% which is 108-127% (Schaefer) and 118-138% (Fox), so that small-scale fisheries in Semarang City are at the level of over-exploited. Based on the fopt analysis, the number of fishing gear used (fexisting) has exceeded the optimum effort with a fishing capacity exceeding 100%, so that small-scale fisheries in Semarang City have experienced overcapacity.

scholarly journals Application of Surplus Production Model to the Yellowfin Tuna Thunnus albacares in the northern and western parts of Aceh waters

2021 ◽  
Vol 869 (1) ◽  
pp. 012072
Author(s):  
A Rahmah ◽  
I Mardhatillah ◽  
A Damora ◽  
M Muhammad ◽  
N Nurfadillah
Keyword(s):  
Economic Value ◽  
Maximum Sustainable Yield ◽  
Yellowfin Tuna ◽  
Production Model ◽  
Purse Seine ◽  
Thunnus Albacares ◽  
Catch Per Unit Effort ◽  
Surplus Production ◽  
Surplus Production Model ◽  
Banda Aceh

Abstract Yellowfin tuna Thunnus albacares is one of pelagic fish that has high potential and economic value in Banda Aceh. Utilization of this resource in Banda Aceh is using purse seine units, with the number of purse seines continuously increasing. Therefore, management needs to be done so that optimal productivity can be maintained. This study discusses the estimation of catch and effort at maximum sustainable yield (MSY) of yellowfin tuna based on catch per unit effort (CPUE) and purse seine production in Banda Aceh during 2013-2018. Mathematical analysis was carried out using the equilibrium approach with the Schaefer model. The highest catch of yellowfin tuna reached 191 tons (July) and the average CPUE for yellowfin tuna was 0.796 tons/trip with CMSY of 2,482 tons/year and EMSY of 2,765 trips/year. From 2015 to 2018, the trend of biomass continued to decline and overfishing occurred during this period.

scholarly journals Determination of the optimum effort for small scale fisheries in Bulukumba regency

2021 ◽  
Vol 919 (1) ◽  
pp. 012014
Author(s):  
A Agus ◽  
Najamuddin ◽  
A R Jalil ◽  
A F Petrus Nelwan
Keyword(s):  
Time Series Data ◽  
Production Method ◽  
Maximum Sustainable Yield ◽  
Series Data ◽  
Small Scale ◽  
Production Data ◽  
Catch Per Unit Effort ◽  
Small Scale Fisheries ◽  
Surplus Production ◽  
Almost All

Abstract This study aims to determine the catch per unit effort (CPUE) or abundance, maximum sustainable yield (Cmsy), optimum effort (Emsy), catch quota, utilization level, and effort of yellowfin tuna (Thunnus albacarez) for small scale fisheries in Bulukumba Regency, using a surplus production method, as well as time-series data for 11 years. According to the results, the CPUE or abundance average, Cmsw, Emsw, and catch quota, were about 4.4284 tons/unit, 720 tons, 184 units of hand line, and 576 tons, respectively. Meanwhile, the sustainable production with actual production showed overfishing, except for 2010 and 2015, while the production data for 2016 – 2020 were unavailable. In addition, the average MSY utilization, catch quota, and average effort levels were 61.9512 %, 77.4397 %, and 86.8352%, respectively. Theoretically, the MSY utilization levels for all years were about 100%, except for 2010 (1.4449 %) and 2015 (23.7581%), as well as 2012, where the value exceeded 100% (364.7357%), while the catch quota for all years was above 100 %, except for 2010 (1.8062 %) and 2015 (29.6976 %). However, the two production data values were unavailable for 2016 – 2020. Also, the effort levels fluctuated while almost all the half values were below 100 %.

scholarly journals Fishery and estimation of Potential yield for Bombayduck Harpodon nehereus along Gujarat coast, India

2020 ◽  
Vol 67 (1) ◽  
Author(s):  
Vinaya Kumar Vase ◽  
Rajan Kumar ◽  
A. D. Nakwa ◽  
Shikha Rahangdale ◽  
J. Jayasankar ◽  
...  
Keyword(s):  
Maximum Sustainable Yield ◽  
Production Model ◽  
Optimum Level ◽  
Catch Per Unit Effort ◽  
Potential Yield ◽  
North West ◽  
Surplus Production ◽  
North East ◽  
The North ◽  
Surplus Production Model

Bombayduck Harpadon nehereus (Hamilton, 1822) is one of the key fishery resources landed along the Indian coast with uniqueness in distribution and exploitation. The resource is known for discontinuous distribution, majorly along the north-west and north-east coasts of India. Gujarat is the lead state to contribute nearly 64.72% (72,949 t) to the total national landings of the resource (11,2705 t) in 2018. Dolnet gear contributes nearly 95% of the total landings of the resource in the region. The landings and the corresponding catch per unit effort (CPUE) showed a fluctuating trend over the study period of 1994-2014. The catches fluctuated between 35,235 t (2016) and 92,188 t (2004), whereas the CPUE oscillated in the range of 15 to 20 kg h-1 (1998) and 30.76 kg h-1 (2003). The period of 1994-2000 was the most productive period with an average catch of 72,133 t, whereas the succeeding decade was the leanest phase with an average annual catch of 50,035 t. The estimated potential yield (= maximum sustainable yield, MSY) was estimated at 73,700 t and 70,108 t using the Bayesian surplus production model (CMSY & BSM) and basic Schaefer surplus production model respectively. The present catch and exploitation levels were found to be close to the optimum level and a further increase in effort for the resource is not recommended.

scholarly journals STATUS PEMANFAATAN IKAN CAKALANG (Katsuwonus pelamis) DI PERAIRAN KABUPATEN LUWU SULAWESI SELATAN

2019 ◽  
Vol 2 (2) ◽  
pp. 216-228
Author(s):  
Muhammad Jamal Alwi ◽  
Hasrun Abdullah ◽  
Ernaningsih Aras
Keyword(s):  
Fishing Effort ◽  
Maximum Sustainable Yield ◽  
Production Model ◽  
Sustainable Yield ◽  
Skipjack Tuna ◽  
Katsuwonus Pelamis ◽  
Surplus Production ◽  
Fish Resources ◽  
Yield Value ◽  
Surplus Production Model

Skipjack tuna (Katsuwonus pelamis), should be managed properly because even though it is renewable, natural resources can be depleted. One approach in managing fish resources is by modeling. The purpose of this study is to determine the maximum sustainable yield, the level of utilization and effort of skipjack tuna. Data on catches as well as catch efforts of skipjack tuna were collected from 9 fisheries year books of Luwu Kabupaten (District). The surplus production model used is the Schaefer, Fox, Walter & Hilborn model. Schaefer model obtained by MSY = 1541.08 tons and Fopt = 243 trips; Fox model obtained maximum sustainable yield value (YMSY) of 1602,244 tons, maximum sustainable fishing effort (fMSY) of 303 units and maximum sustainable CpUE value (UMSY) of 5.29 tons trip-1; the Walter & Hilborn model found potential stocks of sustainable reserves (Be) skipjack in Luwu district amounted to 935.72 tons year-1. Utilization rates of the skpjack tuina indicate the fish is still under exploitation.

scholarly journals Marine Sustainable Yield Analysis of Pelagic Fisheries in Sea Based on Catch Landing data From Tumumpa Fishery Harber, Manado North Sulawesi

2017 ◽  
Vol 6 (1) ◽  
pp. 21
Author(s):  
David Y Rumambi ◽  
Unstain N. W. J. Rembet ◽  
Joudy R. R. Sangari
Keyword(s):  
Fishing Effort ◽  
Maximum Sustainable Yield ◽  
Pelagic Fish ◽  
Production Model ◽  
Sustainable Yield ◽  
Research Activity ◽  
Fish Stocks ◽  
Surplus Production ◽  
North Sulawesi ◽  
Surplus Production Model

This research activity took place in Manado City, North Sulawesi Province with activities centered on the Tumumpa Fishery Harbor (PPP). The data were recorded from capture fisheries activity conducted in the Sulawesi Sea and its surroundings landed in the Tumumpa Fishery Harbor. The purpose of this study was to analyze the stock value and Maximum Sustainable Yield (MSY) of pelagic fish in the Sulawesi Sea based on the approach of the surplus production model (Model Schaefer). This research is expected to be used as a consideration in the management of pelagic fish stocks in the Sulawesi Sea, and can be used as a basis for further research. This research uses secondary data collection method in the form of statistical document and record available. The data taken, including fish catch and fishing effort or effort (trip), from 2012 to 2016 (5 years). The results show that production value is inversely proportional to the value of effort, where the value of production from 2012 to 2016 has decreased every year, while the value of effort from 2012 to 2016 has increased. This condition indicates that the presence of pelagic fish stocks in the Sulawesi Sea and surrounding areas has been and is experiencing a decline that impacts on the decrease of production every year with a large percentage and this condition also indicates the occurrence of potentially overfishing. The value of MSY utilization of capture fishery resources in the Sulawesi Sea based on Tumumpa Fishery Harbor data were 16,305.45 tons / year for HMSY and 1,664,59 trips / year for EMSY, with TAC of 13,044.36 tons / year.Keywords :  Capture fishery, MSY, Pelagic, Surplus Production Model, Tumumpa ABSTRAK Kegiatan penelitian ini berlangsung di Kota Manado, Provinsi Sulawesi Utara dengan kegiatan berpusat di Pelabuhan Perikanan Pantai (PPP) Tumumpa Manado. Aktivitas perikanan tangkap yang ditelaah berlangsung di kawasan perairan Laut Sulawesi dan sekitarnya berdasarkan data PPP Tumumpa Manado. Tujuan dari penelitian ini adalah untuk menganalisis nilai stok dan Maximum Sustainable Yield (MSY) ikan pelagis di Laut Sulawesi berdasarkan pendekatan model produksi surplus (Model Schaefer). Penelitan ini diharapkan dapat digunakan sebagai bahan pertimbangan dalam pengelolaan stok ikan pelagis di Laut Sulawesi dan sekitarnya, serta dapat digunakan sebagai dasar untuk penelitian selanjutnya. Penelitian ini menggunakan metode pengumpulan data sekunder berbentuk dokumen. Data yang diambil adalah data tangkapan ikan dan upaya penangkapan ikan atau effort (trip), dari tahun 2012 sampai dengan 2016 (5 Tahun). Hasil penelitian menunjukkan nilai produksi berbanding terbalik dengan nilai effort, di mana nilai produksi dari tahun 2012 sampai 2016 mengalami penurunan setiap tahunnya, sedangkan nilai effort dari tahun 2012 sampai tahun 2016 mengalami peningkatan. Kondisi yang terjadi ini mengindikasikan bahwa keberadaan stok ikan pelagis di Laut Sulawesi dan sekitarnya telah dan sedang mengalami penurunan yang berdampak pada penurunan produksi setiap tahun dengan persentase yang cukup besar di mana kondisi ini mengindikasikan terjadinya overfishing. Nilai MSY pemanfaatan sumber daya perikanan tangkap di Laut Sulawesi berdasarkan data PPP Tumumpa Manado sebesar 16.305,45 ton/tahun untuk HMSY, dan 1.664,59 trip/tahun untuk EMSY, dengan TAC sebesar 13.044,36 ton/tahun.Kata Kunci: Perikanan Tangkap, MSY, Pelagis, Model Produksi Surplus, Tumumpa

scholarly journals PENENTUAN STATUS PEMANFAATAN DAN SKENARIO PENGELOLAAN IKAN CAKALANG (Katsuwonus pelamis) YANG TERTANGKAP DI PERAIRAN BOLAANG-MONGONDOW SULAWESI UTARA

2014 ◽  
Vol 14 (1) ◽  
pp. 9 ◽  
Author(s):  
John S Kekenusa ◽  
Victor N.R Watung ◽  
Djoni Hatidja
Keyword(s):  
Maximum Sustainable Yield ◽  
Production Model ◽  
Sustainable Yield ◽  
Potential Yield ◽  
Katsuwonus Pelamis ◽  
Effort Level ◽  
Surplus Production ◽  
North Sulawesi ◽  
Surplus Production Model ◽  
The Status

PENENTUAN STATUS PEMANFAATAN DAN SKENARIO PENGELOLAANIKAN CAKALANG (Katsuwonus pelamis) YANG TERTANGKAP DI PERAIRANBOLAANG-MONGONDOW SULAWESI UTARAABSTRAKIkan Cakalang (Katsuwonus pelamis L.), perlu dikelola dengan baik sebagai sumber daya alam terbarukan, tetapi semakin habis atau punah. Salah satu pendekatan dalam pengelolaan sumberdaya ikan adalah dengan pemodelan. Analisis dilakukan, bertujuan untuk mendapatkan model terbaik untuk model surplus produksi adalah Maximum Sustainable Yield (MSY), dan untuk mendapatkan pemanfaatan cakalang dan tingkat usaha. Data yang digunakan untuk model produksi surplus dikumpulkan dari data hasil tangkapan cakalang yang disediakan oleh Dinas Kelautan Dan Perikanan Kabupaten Bolaang Mongondow Provinsi Sulawesi Utara. Model terbaik Surplus Produksi dapat digunakan untuk menilai potensi hasil cakalang adalah  model Fox. Upaya optimal per tahun secara biologi EMSY adalah 3.876 perjalanan. Hasil optimal secara biologi CMSY 1,505.00 ton per tahun. Tingkat pemanfaatan untuk tahun 2005 adalah 124,48%, dengan tingkat usaha 110,96%. Hasil tangkapan untuk tahun 2005 sudah di atas nilai MSY, yang menunjukkan overfishingKata kunci: ikan cakalang, Model surplus produksi, Maksimum Sustainable Yield,Bolaang MonogndowDETERMINATION OF THE STATUS OF UTILIZATION AND MANAGEMENTSCENARIOS SKIPJACK (Katsuwonus pelamis L.) CAUGHT IN THEBOLAANG MONGONDOW BEACH, NORTH SULAWESIABSTRACTSkipjack (Katsuwonus pelamis L.), needs to be managed well as a renewable natural resources, but vunerable to depletion or extinction. One approach in fish resource management is by modeling. Analysis were carried out, aimed to get the best model for surplus production model, to assess the Maximum Sustainable Yield (MSY), and to get the skipjack utilization and effort level. Data used for surplus production model were collected from skipjack landings data provided by Marine and Fisheries Service (Dinas Kelautan dan Perikanan) of Bolaang-Mongondow Regency and North Sulawesi Province. The best Surplus Production Model that can be used to assess the skipjack potential yield is the Fox model. The optimum effort per year biologically EMSY is 3,876 trips. The optimum yield biologically CMSY is 1,505.00 tons per year. Utilization level for 2005 was 124.48 %, with effort level 110.96 %. The catch for 2005 had already above the MSY value, which shows an overfishing.Keywords : Skipjack, Surplus Production Model, Maximum Sustainable Yield, Bolaang Mongondow

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