scholarly journals Bioeconomic Approach for Assessing Status of Trawl Fishery in the Straits of Malacca

2021 ◽  
Vol 34 (4) ◽  
Author(s):  
HOONG SANG WONG ◽  
◽  
CHEN CHEN YONG ◽  
AZMAH OTHMAN
Keyword(s):  
Fishery Management ◽  
Statistical Tests ◽  
Fishing Effort ◽  
Current Status ◽  
Fish Stock ◽  
Base Case ◽  
Current Effort ◽  
Price Inflation ◽  
Trawl Fishery ◽  
Straits Of Malacca

The Straits of Malacca provides half of Malaysia’s total marine fish and seafood supply. Due to depleted fish stock, the Malaysian Government has established a comprehensive legal framework to reduce overfishing in the Straits over the last five decades. However, there are limited scientific studies on the current status of stock recovery. This paper aims to use bioeconomic approach to determine the current trawl fishery status in the Straits. Various statistical tests showed that the Clarke-Yoshimoto-Pooley model was better than the Schnute model in predicting and thus used to estimate the crucial bioeconomic parameters. The current yield and standardised effort of 239,692 tonnes and 931,692 standard fishing days were very close to the estimated biological maximum sustainable yield (239,915 tonnes) and above 18 % of the standardised effort (763,649 standard fishing days) to achieve it. The maximum economic yield was estimated at 201,542 tonnes while the corresponding standardised effort was 396,799 standard fishing days indicating serious economic overfishing in the Straits. If the current effort can be reduced by 57 %, fish biomass and economic rent will increase by 97 % and 835 %, respectively. A price sensitivity analysis predicted that demand-pull fish price inflation could exacerbate the overfishing problem, particularly under unrestrained environment. A 50 % increase in price could lead to a 132 % increase in fishing effort from the base case. The findings of this paper provide valuable insights for fishery managers to refine their existing fishery management program to achieve sustainable fishery for the future.

scholarly journals Catch shares drive fleet consolidation and increased targeting but not spatial effort concentration nor changes in location choice in a multispecies trawl fishery

2019 ◽  
Vol 76 (12) ◽  
pp. 2377-2389 ◽  
Author(s):  
Peter T. Kuriyama ◽  
Daniel S. Holland ◽  
Lewis A.K. Barnett ◽  
Trevor A. Branch ◽  
Robert L. Hicks ◽  
...  
Keyword(s):  
Fishery Management ◽  
Location Choice ◽  
Fishing Effort ◽  
Fishing Activity ◽  
Catch Shares ◽  
Capital Costs ◽  
Trawl Fishery ◽  
Management Objectives ◽  
The Us ◽  
Fisher Behavior

Catch share systems are generally expected to increase economic rents in fisheries by increasing harvest efficiency, reducing capital costs through consolidation, and increasing the value of landed catch. However, these benefits may have costs, as consolidation and the potential for associated change in spatial distribution in landings can hinder social objectives such as maintaining access for fishery-dependent communities and small owner-operators. Achievement of such fishery management objectives are determined by changes in fisher behavior, which may be complex and difficult to predict. Predicting fisher behavior is particularly challenging in multispecies fisheries, in which the mix of species is a determinant of where and when fishing effort and landings occur. We evaluate changes in overall fishing effort, species targeting, and determinants of fishing location choice in response to catch shares in the US West Coast Groundfish Trawl Fishery. We found reductions in total fishing effort, increased targeting of some species, and no evidence of spatial effort concentration. Key determinants of location choice (distance, expected revenue, and recently fished locations) were similar among time periods, but after catch shares there was more avoidance of areas that lacked recent fishing activity or associated information with which to develop expectations of catch and bycatch. Additionally, location choice remained constant with up to 100-fold financial penalties on bycatch species.

scholarly journals KEBIJAKAN DAN STRATEGI PENGELOLAAN PERIKANAN TANGKAP DI DANAU TOBA PASKA INTRODUKSI IKAN BILIH

2017 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Sonny Koeshendrajana
Keyword(s):  
Fishery Management ◽  
Positive Impact ◽  
Management Practice ◽  
Fishing Effort ◽  
Survey Method ◽  
Fish Stock ◽  
Fishing Gear ◽  
Management Options ◽  
Rapid Appraisal ◽  
Descriptive Method

Pengelolaan perikanan tangkap pada hakekatnya adalah pengendalian penangkapan (control of fishing) dan pengendalian upaya penangkapan (control of fishing effort) melalui sejumlah opsi pengelolaan yang diimplementasikan oleh pihak pengelola (management authority). Kajian kebijakan dan strategi pengelolaan perikanan tangkap di perairan Danau Toba pasca introduksi ikan bilih (Mystacoleucus padangensis Bleeker) dimaksudkan untuk memberikan panduan praktek pengelolaan yang mampu menjamin keberlanjutan perikanan ikan bilih di perairan Danau Toba. Metode survei penilaian cepat (rapid appraisal survey) dan review literatur digunakan dalam kajian ini; sedangkan metode analisis deskriptif tabulatif dan content analysis digunakan untuk membantu pengambilan kesimpulan. Hasil kajian menunjukkan bahwa ikan bilih yang ditebarkan ke Danau Toba 2.840 ekor dengan ukuran panjang berkisar antara4,1-5,7 cm dan bobot 0,9-1,5 g pada tahun 2003 telah mampu memberikan dampak positif secara ekonomi dan sosial bagi masyarakat sekitar Danau Toba. Penggunaan alat tangkap yang kurang ataupun tidak terkontrol telah memberikan indikasi penurunan jumlah dan kualitas stok ikan bilih; sehingga implementasi opsi pengelolaan yang meliputi pengembangan kawasan konservasi dan pengaturan serta pengendalian penggunaan alat tangkap bagan untuk menjamin keberlanjutan perikanan ikan bilih perlu segera diterapkan oleh pihak pengelola.Fishery management is essentially a control of fishing and fishing effort through various management options implemented by a management authority. Studies on policies and strategies for fishery management in the Lake Toba water body post introducing or stocking of bilih fish (Mystacoleucus padangensis Bleeker)aimed at providing a sort of guidelines for management practice in order to ensure sustainability of such the fishery. Rapid appraisal survey method and literature review were used in this study. Analysis of the study used a descriptive method compounded by cross tabulated data techniques and a content anaysis method. Results show that introducing of bilih fish in the Toba Lake amounted of 2,840 piece with body length of 4.1-5.7 cm and body weight of 0.9-1.5 g in 2003 has been able to provide a positive impact to social and economic aspects of the society surrounding the Lake Toba. However, the use of uncontrolled fishing and fishing effort was led to indication of decreasing quantitatively and qualitatively such of the fish stock; therefore, implementation of management options of developing a protected or conserved area and controlled the use of bagan fishing gear has to be imposed by management authority.

Long-term changes in fish pond management as ‘an unplanned ecosystem experiment’: importance of zooplankton structure, nutrients and light for species composition of cyanobacterial blooms

1995 ◽  
Vol 32 (4) ◽  
pp. 187-196 ◽  
Author(s):  
L. Pechar
Keyword(s):  
Species Composition ◽  
Fishery Management ◽  
Grazing Pressure ◽  
Organic Fertilizers ◽  
Cyanobacterial Blooms ◽  
Fish Stock ◽  
Fish Ponds ◽  
Single Filament ◽  
The 1950S ◽  
Water Blooms

The study presents data on the species composition of cyanobacterial water blooms in Czech fish ponds from the 1950s to the 1990s. Since the 1950s, a shift from large-colonial Aphanizomenon flos-aquae var. flos-aquae through Microcystis aeruginosa and small-colonial species of Anabaena to single-filament species (Planktohrix agardhii, Limnothrix redekei, Aphanizomenon gracile) or single-cell forms (Microcystis ichtyoblabe), has been observed. The changes in the species composition of the water blooms are closely related to changes in fishery management (increase in fish stock, increase in application of organic fertilizers). At present the high predation of fish upon zooplankton results in elimination of large colonial blooms of A. flos-aquae associated with large filtering zooplankton (Daphnia). Low grazing pressure of zooplankton, low light conditions and low N:P ratios are suitable conditions for mass development of the small species of cyanobacteria. High pH is not necessary to achieve cyanobacteria dominance.

scholarly journals Sustainable exploitation of temperate fish stocks

2009 ◽  
Vol 6 (1) ◽  
pp. 124-127 ◽  
Author(s):  
Henrik Sparholt ◽  
Robin M. Cook
Keyword(s):  
Species Interactions ◽  
Fishery Management ◽  
Regional Scale ◽  
Single Species ◽  
Fishing Effort ◽  
Theoretical Concept ◽  
Maximum Sustainable Yield ◽  
Production Model ◽  
The Status ◽  
Long Time

The theory of maximum sustainable yield (MSY) underpins many fishery management regimes and is applied principally as a single species concept. Using a simple dynamic biomass production model we show that MSY can be identified from a long time series of multi-stock data at a regional scale in the presence of species interactions and environmental change. It suggests that MSY is robust and calculable in a multispecies environment, offering a realistic reference point for fishery management. Furthermore, the demonstration of the existence of MSY shows that it is more than a purely theoretical concept. There has been an improvement in the status of stocks in the Northeast Atlantic, but our analysis suggests further reductions in fishing effort would improve long-term yields.

A Synthesis of Knowns, Unknowns, and Policy Recommendations from the Sea Lamprey International Symposium

1980 ◽  
Vol 37 (11) ◽  
pp. 2202-2208 ◽  
Author(s):  
Carl J. Walters ◽  
George Spangler ◽  
W. J. Christie ◽  
Patrick J. Manion ◽  
James F. Kitchell
Keyword(s):  
International Symposium ◽  
Large Scale ◽  
Fishery Management ◽  
Field Experiments ◽  
Lake Trout ◽  
Sea Lamprey ◽  
Future Research ◽  
Fish Stock ◽  
Total Production ◽  
Pilot Studies

The Sea Lamprey International Symposium (SLIS) has provided a broad spectrum of facts and speculations for consideration in future research and management programs. Many aspects of the laboratory biology and field life history of the sea lamprey (Petromyzon marinus) are now well understood. There is little question that it can now be controlled by chemical larvicides, and perhaps in the future by more efficient integrated control programs. There is correlative evidence (wounds, scars, catch curves) that lamprey caused major mortalities in some fish species, and that control in conjunction with stocking has lead to remarkable recoveries of salmonid stocks in the Great Lakes. However, there are great gaps in understanding about just what the lamprey does under field conditions, and it is not yet possible to reject several hypotheses that assign lamprey a minimum or transient role in fish stock changes. Further studies on details of lamprey biology are, in themselves, unlikely to fill the gaps; one alternative is to conduct a large-scale field experiment involving cessation of lamprey control while holding other factors (fishing, stocking) as steady as possible. If it is decided to proceed with management on the assumption that lamprey are important, without the major field experiments to confirm it, then at least the following steps should be taken: (1) the chemical treatment program should be reviewed in detail, with a view to finding treatment schedules that will minimize frequency and dose rates for lampricide applications; (2) pilot studies on alternative control schemes (sterile male, attractants, barriers) should only be funded if they are statistically well designed (several replicate and control streams), and involve quantitative monitoring of lamprey spawning success and subsequent total production of transforming larvae; (3) the lake trout (Salvelinus namaycush) stocking program should be maintained at its present level, and should involve diverse genotypes rather than a few hatchery strains; (4) growth in the sport fisheries for lake trout should be curtailed, and commercial fisheries should not yet be permitted; (5) a multispecies harvesting policy should be designed that takes into account the buffering effect of each species on lamprey mortality suffered by others (i.e. should some species not be harvested at all, and viewed instead as buffers for more valuable species?); and (6) a program should be developed for restoring, by culture if necessary, native forage species in case the introduced smelt and alewife should collapse under pressure from fishing and prédation by the growing salmonid community.Key words: sea lamprey, proposed research, fishery management, mathematical models, population dynamics

scholarly journals Accounting and disciplinary methods in fishery management

2021 ◽  
Vol 34 (9) ◽  
pp. 218-249
Author(s):  
Stefania Servalli ◽  
Antonio Gitto
Keyword(s):  
Fishery Management ◽  
18Th Century ◽  
The State ◽  
Fish Stock ◽  
Control Mechanisms ◽  
Local Authorities ◽  
Local Conditions ◽  
Content Type ◽  
Papal States

PurposeThe purpose of this study is to contribute to the research related to “the interplay between accounting and the state, politics, and local authorities in the broad government and administration of food for sustainability of populations” (Sargiacomo et al., 2016). Considering contemporary examples and investigating the genealogy of an 18th-century reform of fishery management (the New Plan), the authors explore the role played by accounting and calculative practices when local authorities intervene using forms of discipline based on control systems that acted on commons (fish), people and space.Design/methodology/approachThis paper is historically grounded on archival research on a fish provisioning case during the 18th century in Ancona, an Italian town on the Adriatic coast. The investigation adopts an approach focussed on the use of disciplinary methods in the terms highlighted by Foucault. This perspective offers a lens capable of revealing the key role of accounting in a period when discipline became “general formulas of domination” (Foucault, 1977) and the Papal States were looking for food provisioning solutions (Foucault, 2007). The study highlights similarities with contemporary fishery management.FindingsThe paper shows that governability of fishery in a commons' logic is not limited by the properties of the good, but rather “it is achieved through the objects and instruments that are deployed to make it possible” (Johnsen, 2014, p. 429). It reveals forms assumed by economic calculation in different eras and their contribution in the art of governing realised by the state (Hoskin and Macve, 2016). The study unveils how accounting effectively operates using “naming and counting” activities (Ezzamel and Hoskin, 2002) based on a system of documents and accounting registers; these have a pivotal role in redefining fishery management and in keeping goods (fish) and people (fishermen) under control. The investigation also highlights the importance of properly quantifying data in fishery management, confirming the literature on the topic (Beddington et al., 2007, p. 1713). In contemporary situations, data refer to quantifying the fish stock in the sea and the consequent estimation of fish catch. In the historical investigation, although environmental protection was not an issue, quantification refers to the fish that entered the town of Ancona, whose estimation was the result of a new calculative approach adopted by local authorities facing fish needs. In addition, it offers early evidence of organised and rational-based control mechanisms that were the result of Enlightened ideas emerging in the Papal States context.Originality/valueDespite the fact that fish represent a fundamental good for governments to act on in response to a population's needs, there has been no attention paid to how governmental authorities have used disciplinary mechanisms to intervene in fishery management or the role played by accounting. This study's novelty is its investigation of fishery, using Foucauldian disciplinary methods to understand accounting's contribution in fishery governance. In addition, this investigation permits to unveil the role of accounting to support one of the main principles of the governance of commons that is represented by the congruence between rules and local conditions (Fennell, 2011, p. 11; Ostrom, 1990, p. 92).

scholarly journals North Sea cod recovery?

2006 ◽  
Vol 63 (6) ◽  
pp. 961-968 ◽  
Author(s):  
Joe Horwood ◽  
Carl O'Brien ◽  
Chris Darby
Keyword(s):  
North Sea ◽  
Gadus Morhua ◽  
Mortality Rates ◽  
Fishing Effort ◽  
Current Status ◽  
Fishing Mortality ◽  
Commercial Fish ◽  
Fish Stocks ◽  
Stock Assessments ◽  
Low Levels

AbstractRecovery of depleted marine, demersal, commercial fish stocks has proved elusive worldwide. As yet, just a few shared or highly migratory stocks have been restored. Here we review the current status of the depleted North Sea cod (Gadus morhua), the scientific advice to managers, and the recovery measures in place. Monitoring the progress of North Sea cod recovery is now hampered by considerable uncertainties in stock assessments associated with low stock size, variable survey indices, and inaccurate catch data. In addition, questions arise as to whether recovery targets are achievable in a changing natural environment. We show that current targets are achievable with fishing mortality rates that are compatible with international agreements even if recruitment levels remain at the current low levels. Furthermore, recent collations of data on international fishing effort have allowed estimation of the cuts in fishing mortality achieved by restrictions on North Sea effort. By the beginning of 2005, these restrictions are estimated to have reduced fishing mortality rates by about 37%. This is insufficient to ensure recovery of North Sea cod within the next decade.

Comments on a model of retail price inflation

1990 ◽  
Vol 117 (2) ◽  
pp. 407-413 ◽  
Author(s):  
A. Kitts
Keyword(s):  
Statistical Tests ◽  
Retail Price ◽  
Financial Model ◽  
Price Inflation

AbstractThe paper comments on the estimation and sensitivity of the retail price inflation component of the stochastic financial model proposed by Professor Wilkie. Statistical tests provide evidence of nonindependence and non-normality of residuals, suggesting non-linearity. However, it is noted that the model is most sensitive to the assumption of long-term mean inflation.

The current status of west sea fisheries resources and utilization in the context of fishery management of Korea

2014 ◽  
Vol 102 ◽  
pp. 493-505 ◽  
Author(s):  
Chang Ik Zhang ◽  
Jung Hyun Lim ◽  
Youjung Kwon ◽  
Hee Joong Kang ◽  
Do Hoon Kim ◽  
...  
Keyword(s):  
Fishery Management ◽  
Current Status ◽  
Fisheries Resources

Fish Stock Indicators as Measure for Sustainability

2015 ◽  
pp. 118-182 ◽  
Author(s):  
Violin S. Raykov ◽  
Ivelina Zlateva
Keyword(s):  
Black Sea ◽  
Fishery Management ◽  
Management Strategies ◽  
Age Determination ◽  
Reproductive Potential ◽  
Local Environment ◽  
Point Of View ◽  
The Black Sea ◽  
Fish Stock ◽  
Mortality Estimation

Particular species may be good indicators of specific environmental factors in their local environment. It was found that one of the main objectives for effective and sustainable management of the fish stocks is to make regular annual assessment of the parental stock biomass, length and weight growth, age determination, mortality estimation and reproductive potential estimation. The Black Sea sprat (Sprattus sprattus L.) is a key species in the Black Sea ecosystem. Small pelagic forage fish and especially local one with shared stocks are very important from ecological (key trophic level) and commercial (intensively exploited) point of view. Fishery management strategies must ensure that fishing mortality will not exceed that which corresponds to MSY, and that the biomass will not fall below a predefined threshold. The goal of the chapter is to define the main objectives and measures for sustainable sprat exploitation in order to be in favour of decision makers and fishery managers.

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