THE BIOLOGICAL OPTIMAL LEVEL OF THE ARAFURA SHRIMP FISHERY

From recent and historical data the natural mortality rate of adult harp seals (Pagophilus groenlandicus) is estimated to be 0.10 which is within the range of previous estimates (0.08–0.11). New estimates of bedlamer and 0-group natural mortality rates were not significantly different from those of adult seals. Pup production estimates from survival indices agreed well with those from sequential population analyses and indicated a decline from about 350 000 animals in the early 1950s to about 310 000 animals in the early 1970s. Over the same period the 1+ population size declined from 2.5 to 1.1 million animals but has been increasing at the rate of 3%/yr since the introduction of quotas in 1972. The relative contribution of the "Front" production to total ("Front" plus Gulf) production during the past decade has fluctuated from 49 to 87%, the average of 64% being very similar to the 61% obtained previously. These fluctuations suggest some interchange between "Front" and Gulf adults and it is concluded that homing in the breeding areas is a facultative rather than obligatory aspect of seal behavior. Thus the heavier exploitation of the "Front" production is probably sufficiently diffused into the total population to avoid serious effects on "Front" production. The maximum sustainable yield of Northwest Atlantic seals harvested according to recent patterns is estimated to be 290 000 animals (80% pups) from a 1+ population size of 1.8 million animals producing 460 000 pups annually. The sustainable yield at present levels of pup production (335 000 animals) is calculated to be 220 000 animals which is substantially above the present TAC of 180 000 animals and coincides with present harvesting strategies designed to enable the seal hunt to increase slowly towards the MSY level. Key words: mortality, production, sustainable yield, population dynamics, marine mammal

Download Full-text

Sustainable Potential of Tuna Fishery Around the Waters of North Sulawesi Province Based on Data from the Bitung Ocean Fisheries Port (PPS)

JURNAL PERIKANAN DAN KELAUTAN TROPIS ◽

10.35800/jpkt.10.1.2019.24414 ◽

2019 ◽

Vol 10 (1) ◽

pp. 18

Author(s):

Donald H. Simanjuntak ◽

Lawrence J. L. Lumingas ◽

Joudy R. R. Sangari

Keyword(s):

Secondary Data ◽

Fishing Effort ◽

Maximum Sustainable Yield ◽

Production Model ◽

Utilization Rate ◽

Sustainable Yield ◽

North Sulawesi ◽

Surplus Production Model ◽

Tuna Fishing ◽

Tuna Fisheries

This research was conducted in the city of Bitung, North Sulawesi Province with activities centered on the Bitung Ocean Fisheries Port (PPS), which began from mid March to April 2019. The fishing activities studied are using the fishing areas around the waters of North Sulawesi Province namely the Sulawesi Sea and The Maluku Sea which are included in WPP 715 and 716 based on tuna catch landed data on PPS Bitung. The purpose of this study was to analyze the value of sustainable potential by looking at the level of utilization and Maximum Sustainable Yield (MSY) of tuna in the waters around North Sulawesi Province based on a surplus production model approach (Schaefer Model). This research is expected to be used as a consideration in the management of tuna stocks around the waters of North Sulawesi Province, and can be used as a basis for further research. This study uses a secondary data collection method in the form of fishery statistics documents. The data used are data from tuna fishing and fishing (effort), from 2014 to 2018 (5 years). The results showed that the sustainable potential of tuna fisheries around the waters of North Sulawesi Province based on North Sulawesi PPS data indicated that, the sustainable potential value of tuna that could be caught was 14,173.51 tons / year which is counted as 80% of the value of tuna resources around the waters of North Sulawesi Province. PPS Bitung data which amounted to 17,716.15 tons / year for Hmsy, 1,200.15 trips / year for Emsy, with an average CPUE value of 2014-2018 of 19 tons / trip. The level of tuna utilization around the waters of North Sulawesi Province is based on data from PPS Bitung in 2014, 2017 and 2018 which indicate that there were indications of overfishing with the largest utilization rate in 2014 which reached a value of 155.09%.Keywords: tuna, Bitung, Bitung PPS, sustainable potential, MSY. ABSTRAKKegiatan penelitian ini berlangsung di Kota Bitung, Provinsi Sulawesi Utara dengan kegiatan berpusat di Pelabuhan Perikanan Samudera (PPS) Bitung, yang dimulai dari pertengahan bulan Maret hingga bulan April 2019. Aktivitas perikanan tangkap yang ditelaah berlangsung di sekitar perairan Provinsi Sulawesi Utara yaitu Laut Sulawesi dan Laut Maluku yang masuk ke dalam WPP 715 dan 716 berdasarkan data tangkapan tuna yang didaratkan di PPS Bitung. Tujuan dari penelitian ini adalah untuk menganalisis nilai potensi lestari dengan melihat tingkat pemanfaatan dan maximum sustainable yield (MSY) ikan tuna di sekitar perairan Provinsi Sulawesi Utara berdasarkan pendekatan model produksi surplus (Model Schaefer). Penelitan ini diharapkan dapat digunakan sebagai bahan pertimbangan dalam pengelolaan stok ikan tuna di sekitar perairan Provinsi Sulawesi Utara, serta dapat digunakan sebagai dasar untuk penelitian selanjutnya. Penelitian ini menggunakan metode pengumpulan data sekunder berbentuk dokumen. Data yang diambil adalah data tangkapan ikan tuna dan upaya penangkapan ikan atau effort (trip), dari tahun 2014 sampai dengan 2018 (5 Tahun). Hasil penelitian menunjukkan potensi lestari perikanan tuna di sekitar perairan Provinsi Sulawesi Utara berdasarkan data PPS Bitung Sulawesi Utara nilai potensi lestari tuna yang bisa ditangkap adalah 14.173,51 ton/tahun 80% dari nilai pemanfaatan sumber daya perikanan tangkap tuna di sekitar perairan Provinsi Sulawesi Utara berdasarkan data PPS Bitung yang sebesar 17.716,15 ton/tahun untuk Hmsy, 1.200,15 trip/tahun untuk Emsy, dengan nilai CPUE rata-rata tahun 2014-2018 sebesar 19 ton/trip. Tingkat pemanfaatan tuna di sekitar perairan Provinsi Sulawesi Utara berdasarkan data PPS Bitung Sulawesi Utara di tahun 2014,2017 dan 2018 sudah yang menandakan adanya indikasi overfishing dengan tingkat pemanfaatan terbesar di tahun 2014 yang mencapai nilai 155,09%.Kata Kunci: ikan tuna, Bitung, PPS Bitung, potensi lestari, MSY.

Download Full-text

Estimation of the Maximum Sustainable Yield and the Optimal Fishing Effort of the Blue Crab (Callinectes sapidus, Rathbun 1896) of Laguna Madre, Tamaulipas, Mexico

Crustacea ◽

10.5772/intechopen.90065 ◽

2020 ◽

Author(s):

Jorge Homero Rodriguez Castro ◽

Sandra Edith Olmeda de la Fuente ◽

Wanda Ortiz Baez ◽

Alfonso Correa Sandoval ◽

Jose Alberto Ramirez de León

Keyword(s):

Blue Crab ◽

Callinectes Sapidus ◽

Fishing Effort ◽

Maximum Sustainable Yield ◽

Sustainable Yield ◽

Laguna Madre

Download Full-text

Evaluating management strategies to implement the recovery plan for Iberian hake (Merluccius merluccius); the impact of censored catch information

ICES Journal of Marine Science ◽

10.1093/icesjms/fsp233 ◽

2009 ◽

Vol 67 (2) ◽

pp. 258-269 ◽

Cited By ~ 7

Author(s):

Ernesto Jardim ◽

Santiago Cerviño ◽

Manuela Azevedo

Keyword(s):

Management Strategies ◽

Maximum Sustainable Yield ◽

Sustainable Yield ◽

Fishing Mortality ◽

Merluccius Merluccius ◽

Total Allowable Catch ◽

Recovery Plan ◽

Stock Biomass ◽

Spawning Stock ◽

The Impact

Abstract Jardim, E., Cerviño, S., and Azevedo, M. 2010. Evaluating management strategies to implement the recovery plan for Iberian hake (Merluccius merluccius); the impact of censored catch information. – ICES Journal of Marine Science, 67: 258–269. Iberian hake assessment revealed an increase in fishing mortality (F) despite enforcement of a recovery plan. Recent landings exceeded the total allowable catch and discarding rates were high. Alternative management strategies based on F control were evaluated with respect to the probability of recovering spawning-stock biomass (SSB), expected profits, and robustness to uncertainty on catch information and stock dynamics. Results showed that the use of censored catch data, i.e. excluding the Gulf of Cádiz or discards, may lead to inappropriate conclusions. Reducing fishing mortality was necessary for SSB to recover. An Fmax strategy with discard reduction showed the highest probability of rebuilding SSB and led the fishery to sustainable exploitation, with an expected %SPR of 30–40% in 2025, mean individual weight in the landings of 450 g in 2015, and yield increasing by >20%. Because of uncertainty in the estimates of maximum sustainable yield, management strategies based on FMSY were least robust, but all strategies were robust to alternative stock–recruit models.

Download Full-text

ANGKA ACUAN SASARAN UNTUK PENGELOLAAN PERIKANAN UDANG LAUT ARAFURA DENGAN TUJUAN BERAGAM

Jurnal Kebijakan Perikanan Indonesia ◽

10.15578/jkpi.5.2.2013.73-85 ◽

2013 ◽

Vol 5 (2) ◽

pp. 73

Author(s):

Purwanto Purwanto

Keyword(s):

Fisheries Management ◽

Programming Model ◽

National Development ◽

Fishing Effort ◽

Optimal Number ◽

Reference Points ◽

Shrimp Fishery ◽

Fishing Vessels ◽

Conflicting Objectives ◽

Arafura Sea

Kriteria pengelolaan perikanan dalam kerangka pembangunan nasional, yaitu pro-growth, pro-poor, pro-job dan pro-environment, mengarahkan pengelolaan perikanan udang di Laut Arafura untuk mengoptimumkan produksi lestari dan keuntungan perikanan, serta meningkatkan keuntungan per kapal dan peluang kerja sebagai nelayan. Masing-masing tujuan tersebut perlu ditetapkan angka acuan sasarannya yang diharapkan dicapai dalam pengelolaan perikanan. Mengingat tujuan tersebut saling bertentangan, sehingga tidak dapat dicapai bersamaan, perlu ditentukan tingkat kompromi optimal diantara tujuan tersebut dan angka acuan sasarannya. Tulisan ini menyajikan model pemrograman matematika untuk optimisasi dengan empat tujuan pengelolaan, serta menggunakannya untuk mengestimasi angka acuan sasaran dan jumlah optimal kapal penangkap. Hasil optimisasi dengan pemberian bobot prioritas yang sama terhadap empat tujuan pengelolaan perikanan dalam kerangka pembangunan nasional menunjukkan bahwa angka acuan sasaran pada tingkat kompromi optimal dicapai dengan pengendalian upaya penangkapan pada tingkat yang setara dengan daya tangkap 512 kapal pukat udang 130 GT. Angka acuan sasaran yang sama dihasilkan dari optimisasi dengan pemberian bobot prioritas yang lebih tinggi terhadap dua tujuan pengelolaan perikanan sesuai dengan Pasal 6 Undang Undang Perikanan tahun 2004.The criteria of fisheries management undertaken in a framework of national development, particularly pro-growth, pro-poor, pro-job and pro-environment, guide the management of shrimp fishery in the Arafura Sea to optimising shrimp production and fishery profit, and increasing per vessel profit and job opportunity as fishers. As those objectives were conflicting that could not be achieved simultaneously, it is necessary to seek an optimal compromise amongst several conflicting objectives and to estimate their target reference points. This paper presents a mathematical programming model accommodating four objectives of fisheries management, and the utilisation of this for estimating the target reference points and the optimal number of fishing vessels. The result of optimisation shows that target reference points at the optimal compromise levels for the four conflicting objectives, with equal priority, of fisheries management supporting the national development could be achieved by controlling fishing effort at the level equal to fishing power of 512 shrimp trawlers of 130 GT. The same target reference points resulted from the analysis providing higher priority to the objectives of fisheries management stated in Article 6 of Fisheries Act of 2004.

Download Full-text

POTENSI LESTARI IKAN SELAR KUNING (Selaroides leptolepis) DI PERAIRAN SELAT SUNDA (Population Dynamics of Yellowstripe Scad (Selaroides leptolepis) in Sunda Strait)

Marine Fisheries Journal of Marine Fisheries Technology and Management ◽

10.29244/jmf.5.1.101-108 ◽

2016 ◽

Vol 5 (1) ◽

pp. 101 ◽

Cited By ~ 2

Author(s):

Maizan Sharfina ◽

Mennofatria Boer ◽

Yunizar Ernawati

Keyword(s):

Economic Value ◽

Fishing Effort ◽

Maximum Sustainable Yield ◽

Growth Patterns ◽

Purse Seine ◽

Sustainable Yield ◽

Market Demand ◽

Salted Fish ◽

Frozen Fish ◽

The One

ABSTRACT Yellowstripe scad included the one of commodity that has an important economic value in the Sunda Strait. Commonly, this species processed by Pandeglang fishermen to be the boiled fish, salted fish, grilled fish, besides it also traded in fresh or frozen fish product. The high market demand can not offset the production of this species from the nature. Therefore, it needed an information about resources of yellowstripe scad in the waters of the Sunda Strait in order to manage it well. The objective of this study was to estimate the maximum sustainable yield (MSY) and the optimum fishing effort (fopt), so that the yellowstripe scad resources in the waters of the Sunda Strait can be utilized optimally and sustainably. Based on the standardization analysis, the purse seine be made the standard fishing gear for estimating the MSY of yellowstripe scad. The yellowstripe scad growth patterns during the study is isometric. Trends of CPUE of the yellowstripe scad fisheries tends to decrease during 2003 to 2013. Then, this species was estimated its maximum sustainable yield (MSY) of 304.50 tons per year, with the optimum fishing effort of 12.478 trips per year. The decline of the catch per fishing effort can indicated that the yellowstripe scad fishing conditions in the Sunda Strait was having the overfishing phenomenon. Key words: Sunda Strait, sustainable potential, yellowstripe scad-------ABSTRAK Ikan selar kuning termasuk salah satu komoditas perikanan yang memiliki nilai ekonomis penting di perairan Selat Sunda. Jenis ikan ini, selain banyak dimanfaatkan oleh nelayan sekitar Kabupaten Pandeglang sebagai ikan pindang, ikan bakar, ikan asin, juga diperdagangkan dalam keadaan segar maupun dibekukan. Tingginya permintaan pasar tidak dapat mengimbangi produksi ikan tersebut di alam. Oleh karena itu, untuk memperoleh informasi mengenai tingkat pemanfaatan sumber daya ikan selar kuning di perairan Selat Sunda, diperlukan suatu kajian mengenai potensi lestari ikan selar kuning. Tujuan dari penelitian ini adalah untuk mengetahui hasil tangkapan maksimum lestari (maximum sustainable yield atau MSY) serta upaya penangkapan maksimum lestari (fopt) sehingga sumberdaya ikan selar kuning di Perairan Selat Sunda dapat dimanfaatkan secara optimal dan berkelanjutan. Berdasarkan hasil standardisasi, alat tangkap standart yang digunakan adalah purse seine. Pola pertumbuhan ikan selar kuning selama penelitian, yaitu isometrik. Hasil perhitungan CPUE menunjukkan adanya produksi yang cenderung menurun dengan upaya penangkapan yang meningkat dari tahun 2003 sampai 2013. Hasil perhitungan potensi hasil tangkapan maksimum lestari (MSY) diestimasi sebesar 304,50 ton per tahun, dan upaya penangkapan optimumnya adalah 12.478 trip per tahun. Penurunan hasil tangkapan per upaya penangkapan dapat dijadikan salah satu indikasi bahwa kondisi penangkapan ikan selar kuning di Perairan Selat Sunda sedang mengalami gejala lebih tangkap atau overfishing. Kata kunci: Selat Sunda, potensi lestari, ikan selar kuning

Download Full-text

RESPONSIBLE FISHERIES MANAGEMENT OF MINI PURSE SEINE IN THE LAMPUNG BAY AREA

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.29244/jitkt.v8i2.15837 ◽

2017 ◽

Vol 8 (2) ◽

pp. 713-728

Author(s):

Yulia Estmirar Tanjov ◽

Roza Yusfiandayani ◽

. Mustaruddin

Keyword(s):

Fishing Effort ◽

Maximum Sustainable Yield ◽

Pelagic Fish ◽

Purse Seine ◽

Sustainable Yield ◽

Catch Per Unit Effort ◽

Small Pelagic Fish ◽

Bay Area ◽

Fisheries Resources ◽

The Status

Lempasing is a Coastal Fishing Port (CFP) which located in Bandar Lampung. It is one of the centers of fisheries activities in the city. One of the fishing gear which operated by most of fishermen in Lempasing is mini purse seine. Mini purse seine fishing activities in the Lampung Bay Area and Lempasing CFP is not in accordance with the conditions of the surrounding waters area. The research was conducted in the Lampung Bay Area and Lempasing CFP, Lampung. This study aims to: 1) determine the status of fisheries resources utilization, 2) to describe the dominant fish caught by mini purse seine. Analysis methods were used in this study namely: 1) Fishing Power Index (FPI), Catch Per Unit Effort (CPUE), and Maximum Sustainable Yield (MSY) to determine the status of fisheries resource utilization. The dominant small pelagic fishes caught were scad fish Selaroides sp., mackerel fish Rastrelliger sp., longnose trevally fish Carangoides chrysophrys. The result showed that Fox model was the best fits models with estimated maximum sustainable yield of 15.5 ton and fishing effort of 992 trip/year for mini purse seine. The longnose trevally fish in lampung bay area in do not exceeded the optimal catch fish condition can be used to sustainably. In these condition is necessary to wisely manage and setting the catches to not exceed the allowable catch of the small pelagic fish, so the stock of small pelagic fish in the Lampung Bay Area can be used sustainably.

Download Full-text

RESPONSIBLE FISHERIES MANAGEMENT OF MINI PURSE SEINE IN THE LAMPUNG BAY AREA

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.28930/jitkt.v8i2.15837 ◽

2017 ◽

Vol 8 (2) ◽

pp. 713

Author(s):

Yulia Estmirar Tanjov ◽

Roza Yusfiandayani ◽

. Mustaruddin

Keyword(s):

Fishing Effort ◽

Maximum Sustainable Yield ◽

Pelagic Fish ◽

Purse Seine ◽

Sustainable Yield ◽

Catch Per Unit Effort ◽

Small Pelagic Fish ◽

Bay Area ◽

Fisheries Resources ◽

The Status

Lempasing is a Coastal Fishing Port (CFP) which located in Bandar Lampung. It is one of the centers of fisheries activities in the city. One of the fishing gear which operated by most of fishermen in Lempasing is mini purse seine. Mini purse seine fishing activities in the Lampung Bay Area and Lempasing CFP is not in accordance with the conditions of the surrounding waters area. The research was conducted in the Lampung Bay Area and Lempasing CFP, Lampung. This study aims to: 1) determine the status of fisheries resources utilization, 2) to describe the dominant fish caught by mini purse seine. Analysis methods were used in this study namely: 1) Fishing Power Index (FPI), Catch Per Unit Effort (CPUE), and Maximum Sustainable Yield (MSY) to determine the status of fisheries resource utilization. The dominant small pelagic fishes caught were scad fish Selaroides sp., mackerel fish Rastrelliger sp., longnose trevally fish Carangoides chrysophrys. The result showed that Fox model was the best fits models with estimated maximum sustainable yield of 15.5 ton and fishing effort of 992 trip/year for mini purse seine. The longnose trevally fish in lampung bay area in do not exceeded the optimal catch fish condition can be used to sustainably. In these condition is necessary to wisely manage and setting the catches to not exceed the allowable catch of the small pelagic fish, so the stock of small pelagic fish in the Lampung Bay Area can be used sustainably.

Download Full-text

An investigation into fisheries interaction effects using Atlantis

ICES Journal of Marine Science ◽

10.1093/icesjms/fsu114 ◽

2014 ◽

Vol 72 (1) ◽

pp. 275-283 ◽

Cited By ~ 13

Author(s):

Michael D. Smith ◽

Elizabeth A. Fulton ◽

Robert W. Day

Keyword(s):

Fisheries Management ◽

Carrying Capacity ◽

Stock Assessment ◽

Single Species ◽

Interaction Effects ◽

Fishing Effort ◽

Maximum Sustainable Yield ◽

Simultaneous Increase ◽

Total Catch ◽

The Impact

Abstract Fisheries management is commonly based on the outputs of single-species stock assessment models. While such models are appropriate for tactical issues such as quota setting, they typically omit explicit trophic interactions between different parts of the ecosystem. To successfully manage multiple fisheries in the same ecosystem, we need to understand how fishing one species may indirectly affect other species. In this paper, we used a simulation model of the southern Benguela ecosystem, built in the Atlantis framework, to explore fisheries interaction effects. We first measured the impact of fishing different stocks individually at FMSY, the hypothetical level of fishing effort which produces maximum sustainable yield (MSY) in a single-species modelling context. We then applied FMSY to all stocks simultaneously and compared the simultaneous yield with the sum of yields from the individual applications of FMSY. Contrary to expectations, the total catch was higher under the simultaneous scenario. We explored our results by studying the influences of trophic interaction between species at different levels of the foodweb, and found that our overall result was driven by two key factors: volumetric dominance of small pelagic fish in the total catch, and asymmetric influences of competition and predation between piscivorous and planktivorous species. The simultaneous increase in fishing pressure across multiple species in the model led to increased effective carrying capacity for small pelagic species (due to reduced competition), but reduced carrying capacity for piscivorous species (due to reduced small pelagic prey). This work has important implications for the design of tactical multispecies models for use in ecosystem-based fisheries management.

Download Full-text

Limits to sustainable fish catch: the case of marine fishery in Kerala

Environment and Development Economics ◽

10.1017/s1355770x11000039 ◽

2011 ◽

Vol 16 (5) ◽

pp. 621-638 ◽

Cited By ~ 1

Author(s):

PREETI KAPURIA

Keyword(s):

Species Diversity ◽

Maximum Level ◽

Fishing Effort ◽

Maximum Sustainable Yield ◽

Current Level ◽

Significant Decline ◽

Sustainable Yield ◽

Simpson Index ◽

Marine Fishery ◽

Fish Catch

ABSTRACTThis study aims to examine the interannual variation in fish biomass and to estimate the maximum sustainable yield (MSY) for the marine fisheries of Kerala, India. Although the productivity of a fishery is known to be dependent on species diversity, this relationship is not widely documented. This paper uses an extended Gordon–Schaefer model that is modified to incorporate species diversity to estimate the MSY levels of catch and the corresponding fishing effort. Species diversity is expressed as both biological and bioeconomic diversity using the Simpson index. The model reports that the actual fishing effort has exceeded the maximum level necessary to support sustainable yield, while the maximum level of catch for maintaining sustainable yield is not known. A comparison of fish landings and effort data across different fishing techniques indicates that there is a potential to decrease the current level of fishing effort without experiencing a significant decline in fish catch.

Download Full-text