scholarly journals DEPLESI SUMBER DAYA IKAN TUNA DAN CAKALANG DI INDONESIA

2019 ◽  
Vol 13 (2) ◽  
pp. 167
Author(s):  
Maulana Firdaus ◽  
Akhmad Fauzi ◽  
A Faroby Falatehan
Keyword(s):  
Resource Depletion ◽  
Production Model ◽  
Economic Potential ◽  
Average Volume ◽  
Negative Numbers ◽  
Average Value ◽  
Surplus Production ◽  
Fish Resources ◽  
Surplus Production Model ◽  
The World

ABSTRAKTuna dan cakalang memiliki potensi ekonomi yang besar di Indonesia. Beberapa penelitian menunjukkan bahwa kedua komoditas ini telah menunjukkan gejala over fishing di dunia, termasuk Indonesia. Penelitian ini bertujuan untuk mengestimasi seberapa besar deplesi ikan tuna dan cakalang di Indonesia. Deplesi sumber daya dihitung melalui perkiraan stok dan tingkat hasil lestari dengan menggunakan model produksi surplus dan estimasi parameter menggunakan metoda Clarke Yoshimoto Pooley (CYP). Nilai deplesi diperoleh dari perkalian volume deplesi dengan unit rent. Hasil penelitian menunjukkan bahwa volume rata-rata deplesi sumber daya ikan tuna dan cakalang pada periode 1992-2015 adalah (-) 2.828 ton per tahun. Rata-rata nilai deplesi sumber daya ikan tuna dan cakalang menunjukkan angka negatif, yaitu (-) Rp131,89 miliar per tahun. Nilai negatif ini menunjukkan bahwa selama periode 1992-2015, stok sumber daya ikan tuna dan cakalang mengalami penurunan sebesar 2.828 ton per tahun dengan nilai potensi kerugian atau kehilangan akibat penurunan stok yang mencapai Rp131,89 miliar per tahun.Title: Tuna And Skipjack Resources Depletion In IndonesiaABSTRACTTuna and Skipjack has a great economic potential in Indonesia. Several studies have shown that these commodities have symptomed of over-fishing in the world, including Indonesia. This study aims to estimate the extent of tuna and skipjack depletion in Indonesia. Resource depletion is calculated through stock estimates and sustainable yield levels using surplus production model and parameter estimation of Clark Yoshimoto Pooley (CYP) method. Depletion value is obtained from multiplication of depletion volume with unit rent. Results of the study showed that the average volume of depletion of tuna and skipjack resources in the period 1992-2015 was (-) 2,828 tons per year. The average value of tuna and skipjack resource depletion showed negative numbers, ie (-) IDR 131.89 billion per year. This negative value indicates that during the period 1992-2015, the stock of tuna and skipjack fish resources decreased by 2.828 tons per year with the potential value of loss or loss due to a decrease in stock which reached IDR131,89 billion per year. 

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 Penentuan Status Pemanfaatan Ikan Teri (Stolephorus sp) di Perairan Selat Lalang Kecamatan Sungai Apit Kabupaten Siak Provinsi Riau

2021 ◽  
Vol 10 (2) ◽  
pp. 81-85
Author(s):  
Zuriati Murni Izur ◽  
Zulkarnaini Zulkarnaini ◽  
Hazmi Arief
Keyword(s):  
Data Analysis ◽  
Open Access ◽  
Reduction Rate ◽  
Secondary Data ◽  
Production Model ◽  
Analysis Method ◽  
Surplus Production ◽  
Fish Resources ◽  
Fisheries Resources ◽  
Surplus Production Model

The anchovies (stolephorus sp) need to be well managed, for although they are open access resources if not properly managed, fisheries resources are poorly maintained and sustainable. One approach to managing fish resources is with a production surplus model. As for the data method used is a secondary data analysis method, which USES a production surplus model. Analysis was done to acquire the best production model that could provide information on the extent of use and the completion of anchovies. Data from catch and catch fish were obtained from the registry service of siak district fisheries and livestock. Analysis suggests that the best surplus production model, which is used to assess the potential for anchovies, is the walter-hilborn model. The level of utilization for 2020 is 70 percent, with a 41% reduction rate. It shows that, anchovies in the lalang strait in the state of moderately expoited.

scholarly journals KERUGIAN SUMBER DAYA IKAN AKIBAT PRAKTIK MARK DOWN KAPAL PENANGKAP IKAN DI INDONESIA

2018 ◽  
Vol 12 (2) ◽  
pp. 133
Author(s):  
Maulana Firdaus ◽  
Yesi Dewitasari ◽  
Radityo Pramoda ◽  
Sonny Koeshendrajana
Keyword(s):  
Good Governance ◽  
Secondary Data ◽  
Resource Depletion ◽  
Economic Loss ◽  
Study Data ◽  
Production Model ◽  
Fishing Vessel ◽  
Sustainable Fisheries ◽  
Fish Resources ◽  
Iuu Fishing

Dampak praktik Illegal Unreported and Unregulated Fishing (IUUF) telah mengakibatkan terganggunya pengelolaan pemanfaatan perikanan yang berkelanjutan dan menimbulkan kerugian ekonomi. Praktik mark down ukuran kapal penangkapan ikan merupakan salah satu penyalahgunaan perizinan dalam konteks praktik IUUF. Penelitian ini bertujuan untuk mengkaji nilai kerugian sumber daya ikan (deplesi sumber daya) akibat praktik “mark down” ukuran kapal penangkap ikan yang dilakukan di Indonesia. Penelitian dilaksanakan pada bulan Maret – April 2017 bersifat ‘desk study’ dan dilengkapi dengan kajian literature terkait. Data sekunder dan primer digunakan dalam penelitian ini. Analisis data dilakukan melalui Pendekatan Surplus Produksi Model Schaefer digunakan dalam penelitian ini. Nilai kerugian sumber daya ikan diketahui berdasarkan nilai deplesinya. Nilai deplesi sumber daya menggunakan pendekatan The Net Price Method. Hasil penelitian menunjukkan bahwa adanya praktik “mark down” telah menyebabkan deplesi sumber daya ikan atau pengurangan aset sumber daya ikan di perairan Indonesia. Besarnya nilai deplesi sumber daya pada tahun 2015 mencapai 9,83 trilyun rupiah dan diprediksi pada tahun 2020 meningkat menjadi 14,55 trilyun rupiah. Kajian merekomendasikan perlunya percepatan pengukuran ulang kapal perikanan dan penerapan sangsi yang tegas terhadap pelanggar sehingga tata kelola pemanfaatan sumber daya perikanan tangkap yang baik yang mampu mewujudkan pengelolaan perikanan yang berkelanjutan di Indonesia. Tittle: Fish Resources Losses Due to Mark Down Fishing Vessel Practiced in IndonesiaThe impact of IUU fishing has resulted in management disorder of sustainable fisheries and it caused economic loss. Markdown in vessels size is one type of manipulation practices of license in IUU fishing. This study aims to analyze the loss value of fish resources (resource depletion) due to the “markdown” practices in Indonesia. The study was basically a desk study completmenting with relevant literatures review during March – April 2015. Primary and secondary data were used in this study. Data were analyzed using the Schaefer surplus production model approached. Loss value of fish resources was estimated in terms of depletion resource value using the Net Price Method. The research found that “mark down” has led to depletion or reduction of fish resources in Indonesian waters. The estimated value of resource depletion in 2015 reached 9.83 trillion rupiahs and it is predicted to rise into 14.55 trillion rupiahs in 2020. The research suggests the need to accelerate the process of re-measuring the size of fishing vessel as well as to impose sanctions for the disobedience of the rules, so that Indonesia could have a good governance in fisheries resource management with sustainable fisheries resources.

scholarly journals Population changes in rattail species on the Chatham Rise

2021 ◽  
Author(s):  
◽  
Kathleen Large
Keyword(s):  
Maximum Likelihood ◽  
Stock Assessment ◽  
Production Model ◽  
Likelihood Method ◽  
Model Parameters ◽  
Important Species ◽  
Surplus Production ◽  
Surplus Production Model ◽  
Abundance Indices ◽  
The Impact

<p>The aim of this project was to conduct a stock assessment to determine the population dynamic characteristics of rattail species taken as bycatch in the hoki, hake and ling fishery on the Chatham Rise. No quantitative assessment of the current size of rattail populations , and how these may have changed over time, has been carried out before. There is interest in the need to quantify the impact of commercial fishing on the rattail populations, as rattails (Macrouridae family) are considered to be an ecologically important species complex in the deep ocean, and there may be the potential for the development of a commercial fishery based on their value as processed fishmeal. The minimum data required for a stock assessment are an abundance index and a catch history. Abundance indices are available for over 20 species of rattail produced from scientific surveys conducted annually on the Chatham Rise since 1992. Catch histories for individual rattail species in the same area are not available. A method was developed to reconstruct commercial catches of rattails from commercial effort data and survey catch and effort data. A surplus production model was fitted to the reconstructed catch data and survey abundance indices, using maximum likelihood and Bayesian methods to estimate model parameters and uncertainty. A surplus production model has two components: an observation model for abundance indices and a process model for population dynamics. Maximum likelihood estimation was applied to a model that specified errors for the observations only, and this produced estimates that had wide confidence intervals. A Bayesian approach was then taken to fit a statespace version of the model that incorporates errors associated with the observation and process models. While the Bayesian method produced more plausible parameter estimates (in comparison to the maximum likelihood method) and parameter uncertainty was reduced, our analysis indicated the posterior estimates were highly sensitive to the specification of different priors. There may be several reasons for these results, including: the small number of observations, lack of contrast in the data and mis-specification of the model. Meaningful estimates of the absolute size of rattail populations are not possible with these results, where estimates can vary by orders of magnitude depending on prior specification. This implies that more work needs to be done to develop more effective methods that can be used to help inform decisions regarding the management of these fish populations. Improving data collection, investigating informative priors and extending/respecifying the model are considered worthwhile avenues of future work to improve stock assessments of rattails.</p>

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

Reference priors for Bayesian fisheries models

2002 ◽  
Vol 59 (9) ◽  
pp. 1492-1502 ◽  
Author(s):  
Russell B Millar
Keyword(s):  
Prior Knowledge ◽  
Population Analysis ◽  
Production Model ◽  
Model Parameters ◽  
Jeffreys Prior ◽  
Unknown Parameters ◽  
Prior Distributions ◽  
Reference Priors ◽  
Surplus Production ◽  
Surplus Production Model

Bayesian models require the specification of prior distributions for all unknown parameters, and this formal utilization of prior knowledge (if any) can be used to great advantage in some fisheries. However, regardless of whether prior knowledge about model parameters is available, specification of prior distributions is seldom unequivocal. This work addresses the problem of specifying default priors for several common fisheries models. To maintain consistency of terminology with the statistical literature, such priors are herein called reference priors to recognize that they can be interpreted as providing a sensible reference point against which the implications of alternative priors can be compared. Here, the Jeffreys' prior is demonstrated for the Ricker and Beverton–Holt stock–recruit curves, von Bertalanffy growth curve, Schaefer surplus production model, and sequential population analysis. The Jeffreys' priors for relevant derived parameters are demonstrated, including the steepness parameter of the Beverton–Holt stock–recruit curve. The sequential population analysis example is used to show that the Jeffreys' prior should not be automatically accepted as a reference prior in all models—this needs to be decided on a case-by-case basis.

Sign in / Sign up

Export Citation Format

Share Document