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.
11.[62 71]economic efficiency estimate of captured fisheries from plateau sta...Alexander Decker
- The study examined the productivity and economics of fisheries at Pandam Lake in Plateau State, Nigeria under a regulated innovation system.
- Data was collected through daily fishing observations over 8 weeks and questionnaires from 30 licensed fishers. Technical, allocative and economic efficiencies were estimated using stochastic frontier production and cost functions.
- The results showed mean technical, allocative and economic efficiencies of 0.91, 0.68 and 0.72 respectively. Socioeconomic characteristics like education, age and extension contact significantly influenced efficiencies.
Optimization of pelagic fishing efforts in muncar area , indonesiaAlexander Decker
This document summarizes an article that analyzed optimal fishing efforts in Muncar, Indonesia to balance biological, technical, social, and economic sustainability. The study used a multiple goal programming model to determine the optimal number of fishing devices (purse seine, gillnet, liftnet) that minimized deviations from sustainability goals. Results recommended reducing purse seine by 4 units and increasing gillnet by 5 units and liftnet by 27 units to balance ecology, social impacts, and economic profits over the long term. Maintaining sustainable yields of pelagic fish species was the highest priority goal.
Optimization of pelagic fishing efforts in muncar area , indonesiaAlexander Decker
This document summarizes an analysis of optimizing pelagic fishing efforts in the Muncar area of Indonesia. Data was collected through surveys of 134 fishermen using purse seine, gillnet, and liftnet fishing devices. The analysis used multiple goal programming to determine optimal fishing efforts based on biological, technical, social, and economic factors. The sustainability scenario recommended reducing purse seine by 4 units and increasing gillnet by 5 units and liftnet by 27 units. The economic profit scenario recommended reducing purse seine by 3 units, increasing gillnet by 15 units, and increasing liftnet by 16 units to maximize profits while maintaining sustainability. The analysis provides recommendations to optimize fishing efforts through reducing overexploitation while improving economic, social
Compilation of package of practices for energy conservation fisheriesAshish sahu
Fishing in India is a major industry employing 145 million people. India ranks second in aquaculture and third in fisheries production. Fisheries contributes to 1.07% of the Total GDP of India. According to the National Fisheries Development Board the Fisheries Industry generates an export earnings of Rs 334.41 billion.[1] According to the Food and Agriculture Organization (FAO) of the United Nations, fish production has increased more than tenfold since 1947 and doubled between 1990 and 2010.[2]Each year, India celebrates July 10 as the National Fish Farmers day.[3]
India has 7,500 kilometres (4,700 mi) of marine coastline, 3,827 fishing villages and 1,914 traditional fish landing centers. India's fresh water resources consist of 195,210 kilometres (121,300 mi) of rivers and canals, 2.9 million hectares of minor and major reservoirs, 2.4 million hectares of ponds and lakes, and about 0.8 million hectares of flood plain wetlands and water bodies.[4] As of 2010, the marine and freshwater resources offered a combined sustainable catch fishing potential of over 4 million metric tonnes of fish. In addition, India's water and natural resources offer a tenfold growth potential in aquaculture (farm fishing) from 2010 harvest levels of 3.9 million metric tonnes of fish, if India were to adopt fishing knowledge, regulatory reforms and sustainability policies.[
Fishery sustainability study with sustainability window (SuWi) analysis in th...robert peranginangin
Sustainable development can be defined in several different ways, but usually, the term refers to the definition given by the Brundtland Commission in the publication of Our Common Future. Sustainable development is often understood by relying on three pillars, namely environmental/ecology, economic and social. The demersal fishery in the South China Sea (Indonesia Fisheries Management Area / IFMA 711) became one of the supporting sectors of the economy of the fishermen communities around of these waters. This study aims to analyze the sustainability of demersal fisheries with the Sustainability Window (SuWi) approach. Demersal fishery sustainability condition in the South China Sea (IFMA 711) waters tend to be better from year to year. However, the width of demersal sustainability window tends to be low and indicate the status of sustainability of demersal fish is not maximal in the South China Sea (IFMA 711). Therefore, care should be taken to manage demersal fishery in the South China Sea (IFMA 711).
Sustainable Development of Dynamic Fisheries and Cost Benefits Analysis with ...ijtsrd
With Gambia’s marine resources abundance, it is appropriate for Gambia’s economic growth to gear towards the fisheries sector. Fishery management in The Gambia is still not operating optimally due to a lack of fisheries management infrastructure.This study has uncovered important aspects of the fishing industry, especially in The Gambia. If the right policies and guidelines are put in place, the majority of waste and the depletion of renewable resources might be avoided. It is possible to maximize utilities without wasting resources. The solutions of the total cost TC , total revenue TR , and price functions of an operation are all given using differential equation.The original equation of Schaefers model forced numerous researchers to shed light on the spatial distribution of fish and fisheries. Using a cost operation model and an analysis of the rate of change over time, the author of this study found that fishing expenses can be decreased without compromising effectiveness or efficiency. The model was also expanded to include non autonomous price and cost characteristics.This study will inspire other academics and researchers to take similar actions to stop the decline and near extinction of the critically important fish fishery, not only in The Gambia but also along the entire coast of West Africa, given that the fishes are highly migratory and a shared resource among the countries in the subregion. Ebrima Bittaye "Sustainable Development of Dynamic Fisheries and Cost-Benefits Analysis with Mathematical Approach" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-7 | Issue-2 , April 2023, URL: https://www.ijtsrd.com.com/papers/ijtsrd55103.pdf Paper URL: https://www.ijtsrd.com.com/mathemetics/other/55103/sustainable-development-of-dynamic-fisheries-and-costbenefits-analysis-with-mathematical-approach/ebrima-bittaye
A review on features and methods of potential fishing zoneIJECEIAES
This review focuses on the importance of identifying potential fishing zones in seawater for sustainable fishing practices. It explores features like sea surface temperature (SST) and sea surface height (SSH), along with classification methods such as classifiers. The features like SST, SSH, and different classifiers used to classify the data, have been figured out in this review study. This study underscores the importance of examining potential fishing zones using advanced analytical techniques. It thoroughly explores the methodologies employed by researchers, covering both past and current approaches. The examination centers on data characteristics and the application of classification algorithms for classification of potential fishing zones. Furthermore, the prediction of potential fishing zones relies significantly on the effectiveness of classification algorithms. Previous research has assessed the performance of models like support vector machines, naïve Bayes, and artificial neural networks (ANN). In the previous result, the results of support vector machine (SVM) were 97.6% more accurate than naive Bayes's 94.2% to classify test data for fisheries classification. By considering the recent works in this area, several recommendations for future works are presented to further improve the performance of the potential fishing zone models, which is important to the fisheries community.
11.[62 71]economic efficiency estimate of captured fisheries from plateau sta...Alexander Decker
- The study examined the productivity and economics of fisheries at Pandam Lake in Plateau State, Nigeria under a regulated innovation system.
- Data was collected through daily fishing observations over 8 weeks and questionnaires from 30 licensed fishers. Technical, allocative and economic efficiencies were estimated using stochastic frontier production and cost functions.
- The results showed mean technical, allocative and economic efficiencies of 0.91, 0.68 and 0.72 respectively. Socioeconomic characteristics like education, age and extension contact significantly influenced efficiencies.
Optimization of pelagic fishing efforts in muncar area , indonesiaAlexander Decker
This document summarizes an article that analyzed optimal fishing efforts in Muncar, Indonesia to balance biological, technical, social, and economic sustainability. The study used a multiple goal programming model to determine the optimal number of fishing devices (purse seine, gillnet, liftnet) that minimized deviations from sustainability goals. Results recommended reducing purse seine by 4 units and increasing gillnet by 5 units and liftnet by 27 units to balance ecology, social impacts, and economic profits over the long term. Maintaining sustainable yields of pelagic fish species was the highest priority goal.
Optimization of pelagic fishing efforts in muncar area , indonesiaAlexander Decker
This document summarizes an analysis of optimizing pelagic fishing efforts in the Muncar area of Indonesia. Data was collected through surveys of 134 fishermen using purse seine, gillnet, and liftnet fishing devices. The analysis used multiple goal programming to determine optimal fishing efforts based on biological, technical, social, and economic factors. The sustainability scenario recommended reducing purse seine by 4 units and increasing gillnet by 5 units and liftnet by 27 units. The economic profit scenario recommended reducing purse seine by 3 units, increasing gillnet by 15 units, and increasing liftnet by 16 units to maximize profits while maintaining sustainability. The analysis provides recommendations to optimize fishing efforts through reducing overexploitation while improving economic, social
Compilation of package of practices for energy conservation fisheriesAshish sahu
Fishing in India is a major industry employing 145 million people. India ranks second in aquaculture and third in fisheries production. Fisheries contributes to 1.07% of the Total GDP of India. According to the National Fisheries Development Board the Fisheries Industry generates an export earnings of Rs 334.41 billion.[1] According to the Food and Agriculture Organization (FAO) of the United Nations, fish production has increased more than tenfold since 1947 and doubled between 1990 and 2010.[2]Each year, India celebrates July 10 as the National Fish Farmers day.[3]
India has 7,500 kilometres (4,700 mi) of marine coastline, 3,827 fishing villages and 1,914 traditional fish landing centers. India's fresh water resources consist of 195,210 kilometres (121,300 mi) of rivers and canals, 2.9 million hectares of minor and major reservoirs, 2.4 million hectares of ponds and lakes, and about 0.8 million hectares of flood plain wetlands and water bodies.[4] As of 2010, the marine and freshwater resources offered a combined sustainable catch fishing potential of over 4 million metric tonnes of fish. In addition, India's water and natural resources offer a tenfold growth potential in aquaculture (farm fishing) from 2010 harvest levels of 3.9 million metric tonnes of fish, if India were to adopt fishing knowledge, regulatory reforms and sustainability policies.[
Fishery sustainability study with sustainability window (SuWi) analysis in th...robert peranginangin
Sustainable development can be defined in several different ways, but usually, the term refers to the definition given by the Brundtland Commission in the publication of Our Common Future. Sustainable development is often understood by relying on three pillars, namely environmental/ecology, economic and social. The demersal fishery in the South China Sea (Indonesia Fisheries Management Area / IFMA 711) became one of the supporting sectors of the economy of the fishermen communities around of these waters. This study aims to analyze the sustainability of demersal fisheries with the Sustainability Window (SuWi) approach. Demersal fishery sustainability condition in the South China Sea (IFMA 711) waters tend to be better from year to year. However, the width of demersal sustainability window tends to be low and indicate the status of sustainability of demersal fish is not maximal in the South China Sea (IFMA 711). Therefore, care should be taken to manage demersal fishery in the South China Sea (IFMA 711).
Sustainable Development of Dynamic Fisheries and Cost Benefits Analysis with ...ijtsrd
With Gambia’s marine resources abundance, it is appropriate for Gambia’s economic growth to gear towards the fisheries sector. Fishery management in The Gambia is still not operating optimally due to a lack of fisheries management infrastructure.This study has uncovered important aspects of the fishing industry, especially in The Gambia. If the right policies and guidelines are put in place, the majority of waste and the depletion of renewable resources might be avoided. It is possible to maximize utilities without wasting resources. The solutions of the total cost TC , total revenue TR , and price functions of an operation are all given using differential equation.The original equation of Schaefers model forced numerous researchers to shed light on the spatial distribution of fish and fisheries. Using a cost operation model and an analysis of the rate of change over time, the author of this study found that fishing expenses can be decreased without compromising effectiveness or efficiency. The model was also expanded to include non autonomous price and cost characteristics.This study will inspire other academics and researchers to take similar actions to stop the decline and near extinction of the critically important fish fishery, not only in The Gambia but also along the entire coast of West Africa, given that the fishes are highly migratory and a shared resource among the countries in the subregion. Ebrima Bittaye "Sustainable Development of Dynamic Fisheries and Cost-Benefits Analysis with Mathematical Approach" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-7 | Issue-2 , April 2023, URL: https://www.ijtsrd.com.com/papers/ijtsrd55103.pdf Paper URL: https://www.ijtsrd.com.com/mathemetics/other/55103/sustainable-development-of-dynamic-fisheries-and-costbenefits-analysis-with-mathematical-approach/ebrima-bittaye
A review on features and methods of potential fishing zoneIJECEIAES
This review focuses on the importance of identifying potential fishing zones in seawater for sustainable fishing practices. It explores features like sea surface temperature (SST) and sea surface height (SSH), along with classification methods such as classifiers. The features like SST, SSH, and different classifiers used to classify the data, have been figured out in this review study. This study underscores the importance of examining potential fishing zones using advanced analytical techniques. It thoroughly explores the methodologies employed by researchers, covering both past and current approaches. The examination centers on data characteristics and the application of classification algorithms for classification of potential fishing zones. Furthermore, the prediction of potential fishing zones relies significantly on the effectiveness of classification algorithms. Previous research has assessed the performance of models like support vector machines, naïve Bayes, and artificial neural networks (ANN). In the previous result, the results of support vector machine (SVM) were 97.6% more accurate than naive Bayes's 94.2% to classify test data for fisheries classification. By considering the recent works in this area, several recommendations for future works are presented to further improve the performance of the potential fishing zone models, which is important to the fisheries community.
An economic study of small-scale tilapia fish farming in Mymensingh district ...Premier Publishers
- The study examined the costs, returns, and resource use efficiency of small-scale tilapia fish farming in Mymensingh district of Bangladesh.
- It found that tilapia fish farming was profitable, with medium farmers achieving the highest benefit-cost ratio of 1.33. Per hectare yields and returns increased with farm size.
- Key variables like human labor, feed costs, and water supply costs had significant positive effects on economic returns, while resource use was found to be inefficient overall. Increasing use of underutilized inputs like labor, feed, and protection chemicals could maximize profits from tilapia farming.
This slide is a pitch deck of OceanEyes Co. ltd. OceanEyes is a marine deep tech venture company. This pitch is based on CEO Tanaka's presentation in SAFET 2023, Bali, Indonesia.
Fishery-dependent data collection provides valuable information for fishery managers to develop management plans. It is important for managers to determine the most important data to collect and implement a data recording system before overfishing occurs. One common mistake is waiting until populations are imperiled before creating management plans. This document discusses various methods for collecting fishery-dependent data, including catch estimates, catch disposition, catch per unit effort (CPUE), and fishing effort measures. It provides examples of calculating CPUE for different gear types like gill nets and longlines. The document also covers raising factors used to expand sample data to total population estimates.
Evaluation of the oyster farming potential of the Cintra bay (southern Morocco)Origins publication
The bay of Cintra is a marine ecosystem located in the southern Moroccan Atlantic known for its
biological richness and therefore for its high fishery productivity. This bay was chosen as a new destination for the
development of aquaculture in the southern regions of Morocco. To highlight its potential in terms of oyster
farming, a first rearing trial of triploid cupped oysters (Crassostrea gigas) as well as parallel monitoring of the
phytoplankton population and ecological parameters were undertaken. The results obtained showed that the oysters
adapt well to the conditions of the new environment where mortality was negligible, or even absent after a month
of launching. In terms of biological performance, the growth of individuals is continuous during the annual cycle
and after eight months the weight could reach 30.5 g which is a minimum weight for marketing. The AFNOR and
Lawrence and Scott indices showed a good physiological state and a better commercial quality of the oysters. The
filling rate of these oysters, with an average weight of 39.7g when lifting, is very high according to the Lawrence and
Scott index (126.3) and the average AFNOR index (around 21.8) rank them in the “Special” category.
The document discusses three potential solutions to challenges facing Ghana's artisanal fisheries:
1) Replacing illegal fishing nets, which would cost GHS 267 million but yield GHS 1.3 billion in benefits over 10 years.
2) Limiting fishing boats and providing training and subsidies for aquaculture, costing GHS 3.8 billion and earning GHS 4.5 billion in benefits.
3) Installing video devices on trawl vessels to reduce illegal practices, costing GHS 22.4 million initially and GHS 10.7 million annually, while increasing artisanal profits by GHS 260 million annually.
The Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docxmehek4
The Dynamics of an Open Access Fishery
Trond Bjørndal; Jon M. Conrad
The Canadian Journal of Economics / Revue canadienne d'Economique, Vol. 20, No. 1. (Feb.,
1987), pp. 74-85.
Stable URL:
http://links.jstor.org/sici?sici=0008-4085%28198702%2920%3A1%3C74%3ATDOAOA%3E2.0.CO%3B2-0
The Canadian Journal of Economics / Revue canadienne d'Economique is currently published by Canadian Economics
Association.
Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at
http://www.jstor.org/about/terms.html. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtained
prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in
the JSTOR archive only for your personal, non-commercial use.
Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained at
http://www.jstor.org/journals/cea.html.
Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printed
page of such transmission.
The JSTOR Archive is a trusted digital repository providing for long-term preservation and access to leading academic
journals and scholarly literature from around the world. The Archive is supported by libraries, scholarly societies, publishers,
and foundations. It is an initiative of JSTOR, a not-for-profit organization with a mission to help the scholarly community take
advantage of advances in technology. For more information regarding JSTOR, please contact [email protected]
http://www.jstor.org
Tue Jan 29 18:36:53 2008
http://links.jstor.org/sici?sici=0008-4085%28198702%2920%3A1%3C74%3ATDOAOA%3E2.0.CO%3B2-0
http://www.jstor.org/about/terms.html
http://www.jstor.org/journals/cea.html
The dynamics of an open access fishery
TROND BJBRNDAL Norwegian School of Economics
JON M. CONRAD Cornell University
Abstract. A discrete time non-linear deterministic model for an open access fishery is
developed and the equilibrium is characterized. The open access exploitation of North
Sea herring during the period 1963-77 is analysed. Alternative production functions are
considered and estimated for the Nonvegian purse seine fishery. The bionomic
equilibrium and approach dynamics are presented when prices and costs are changing.
The results indicate that the resource stock was saved from possible extinction by the
closure of the fishery at the end of the 1977 season.
Sur la dynumique d'une zone de pgches quund l'entrke est libre. Les auteurs developpent
un modele deterministe non-lineaire en temps discret d'une zone de p&ches ou l'entree
est libre et definissent les caracteristiques de l'equilibre. L'exploitation du hareng de la
Mer du Nord qui s'est faite sans entraves B l'entrte pendant la periode 1963-1977 est
analysee avec ce modele. Des fonctions de production de rechange sont examinees et
calibrkes pour la p&c ...
System design, sustainable production and water quality research for Recircul...IRJET Journal
This document summarizes a student project to design a three-stage water filtration system for a Recirculating Aquaculture System (RAS) to increase fish survival rates. The system includes a 1,000 liter culture tank stocked with 100 tilapia fish. Water flows through mechanical, biological, and UV filtration stages before being recirculated. The mechanical filter removes solid waste using various mesh screens and media. The biological filter uses biomedia like bio-ceramic rings to nitrify waste with the help of bacteria. Finally, the UV filter uses a quartz tube to disinfect water with UV light before recirculation. The design was optimized for factors like compactness, efficiency, cost-
Preliminary Report on Economic Valuation of Ecosystem Services of Guinea Curr...Iwl Pcu
Presentation from the focused learning discussion on economic valuation at the 4th GEF Biennial International Waters Conference.
Chidi Ibe
Guinea Current LME
Chika Ukwe
UNIDO
This document summarizes a study that used geographic information systems (GIS) to determine suitable areas for developing floating net cage aquaculture in Pelabuhan Ratu Bay, Indonesia. Water quality parameters were measured at locations throughout the bay from 2007-2008. The data was analyzed spatially using GIS to classify suitability. The results showed that 8,500 hectares (98% of the total area) were very suitable, 93 hectares were suitable, and 0.4 hectares were not suitable for floating net cage aquaculture. The water quality was found to be suitable for aquaculture based on comparisons to standards. The study concluded most of the bay is very suitable for developing floating net cage aquaculture and
Geographic information system application for determiningPrama Hartami
This document summarizes a study that used geographic information systems (GIS) to determine suitable areas for floating net cage aquaculture in Pelabuhan Ratu Bay, Indonesia. Spatial analysis of environmental and water quality parameters identified approximately 8,500 hectares, or 98% of the study area, as very suitable for net cage aquaculture. The analysis incorporated 12 biophysical variables and assigned scores to classify suitability. The results can help optimize sustainable aquaculture development and fishery production in the region.
This document summarizes a paper presented at an international conference on marine technology in Malaysia in 2012. The paper discusses quantifying greenhouse gas emissions from ships to support decision making and rulemaking by the International Maritime Organization. Specifically, it measures the concentrations of carbon dioxide and nitrogen dioxide emitted from a university research vessel during different operating modes to validate models for calculating emissions. Reducing greenhouse gas emissions from shipping is important because the industry accounts for a growing share of global emissions.
1. The team developed a project to improve fishermen's incomes by designing a new fishing boat and improving fishing gear and operations.
2. They identified factors affecting catch volumes like weather, crew skills, and finding fish. The team defined controllable and uncontrollable problem domains to systematically address issues.
3. Proposed solutions included designing a small-waterplane-area twin hull (SWATH) boat for safer operation in rough seas, developing forward fish detection, and mechanizing net handling to reduce labor. The project aims to benefit future research and develop Malaysia's fishing industry.
Bioeconomic analysis of marine fish production in west bengalAlexander Decker
This document summarizes a study on bioeconomic analysis of marine fish production in West Bengal, India. It aims to estimate maximum sustainable yield (MSY), maximum economic yield (MEY), and open access yield (OAY) for coastal fisheries in the region using historical catch data and a primary survey of costs and returns. The study applies Schaefer's surplus production model to estimate MSY from catch and effort data. It develops bioeconomic models to define MEY as the point where marginal revenue equals marginal cost, and OAY as the point where total revenue equals total costs, indicating zero profits. The results will inform policy suggestions to promote sustainable development and fisher welfare.
Using Systems Engineering Technology to Improve Efficiency of Small Oyster Fa...IRJET Journal
This document discusses using systems engineering techniques to improve the efficiency of small oyster farming operations in the Chesapeake Bay. It aims to develop and evaluate a process to enhance oyster farming through a systems approach. Class diagrams and a Python simulation model are developed to represent the oyster farming process from seedlings to market delivery. Timing data was collected from a small oyster farm to inform the models. The models can be used to analyze the farming system and identify potential bottlenecks or areas for improvement. The overall goal is to help small oyster farmers in the Chesapeake Bay optimize their practices and increase profitability.
Remotely sensed data of sea surface temperature, chlorophyll, and wind patterns from satellites are used to locate Potential Fish Zones (PFZ) in Indian seas. Satellites and instruments like sonar and radar are currently used to find areas where fish aggregate. In the past, PFZ forecasts were based solely on sea surface temperature maps, but now also incorporate ocean color data from sensors to provide information about conditions below the surface. The Potential Fishing Zone advisories generated from this remote sensing data have benefited fishermen in India by reducing search times, saving on fuel and labor, and increasing incomes.
Population dynamics of 15 fish species in Grand-Lahou lagoon (West Africa, Cô...Open Access Research Paper
This study described growth, mortality, recruitment patterns and exploitation rates of 15 fish species in Grand-Lahou lagoon (Côte d’Ivoire). Monthly length-frequency data collected from artisanal fisheries from November 2013 to October 2014 were analyzed with FiSAT software using the ELEFAN package to estimate the population parameters of fishes. Asymptotic values for total length (L∞) ranged from 15.75 cm for Synodontis schall to 59.80 cm for Trachinotus teraia. Growth rate (k) varied from 0.19 for Coptodon guineensis to 0.98 for Caranx hippos. The growth performance index estimates were close to the values found by other authors for most of the fish species. The total mortality (Z) high values were recorded for Synodontis schall (Z= 4.15 year-1; M = 2.50 year-1) Schilbe mandibularis (Z= 2.19 year-1; M=1.33 year-1). Fishing mortality (F) and exploitation rate (E) were found to be less than the optimum levels of exploitation for most fish species. The exploitation rate (E) was higher than the maximum sustainable yield (Emax) for Caranx hippos and higher than E0.5 for Eucinostomus melanopterus, Elops lacerta and Synodontis schall. Recruitment was noted as year-round and bimodal for most studied populations. These results demonstrate that some fish stocks necessitate effective management measures particularly C. hippos, E. melanopterus, E. lacerta and S. schall.
Mathematical models can help to better manage fishing - Encyclopedia of the E...TeXt10
Fishing provides an important part of the food for people in some developing countries. This can lead to a worrying cascade of overfishing, collapsing catches
and rising market prices, and the extinction of many species. How can we prevent this situation from becoming catastrophic and, on the contrary, stabilize it?
Mathematical modelling, by coupling ecological and economic dynamics, provides a better understanding of the dynamics of fisheries systems.
The International Journal of Engineering and Science (The IJES)theijes
This document analyzes sea wave transmission through mangrove forests of Rhizophora sp. in Indonesia. Measurements were taken in natural wave tanks constructed within the mangrove forest. Wave period, height, and transmission were measured using sensors. Porosity and transmission coefficients were calculated. Results showed transmission coefficients decreased with increasing wave steepness and porosity. The mangroves reduced wave heights by 57.73% at high porosity, demonstrating their ability to attenuate sea waves and protect the coastline from erosion.
Presentation about UNCLOS surplus concept in the frame of the EU Common Fisheries Policy to the Conference "Global Trends in Fisheries Governance" organized by the Swedish Agency for Marine and Water Management Rosenbad Conference Centre, Stockholm, 29–30 January 2014
An economic study of small-scale tilapia fish farming in Mymensingh district ...Premier Publishers
- The study examined the costs, returns, and resource use efficiency of small-scale tilapia fish farming in Mymensingh district of Bangladesh.
- It found that tilapia fish farming was profitable, with medium farmers achieving the highest benefit-cost ratio of 1.33. Per hectare yields and returns increased with farm size.
- Key variables like human labor, feed costs, and water supply costs had significant positive effects on economic returns, while resource use was found to be inefficient overall. Increasing use of underutilized inputs like labor, feed, and protection chemicals could maximize profits from tilapia farming.
This slide is a pitch deck of OceanEyes Co. ltd. OceanEyes is a marine deep tech venture company. This pitch is based on CEO Tanaka's presentation in SAFET 2023, Bali, Indonesia.
Fishery-dependent data collection provides valuable information for fishery managers to develop management plans. It is important for managers to determine the most important data to collect and implement a data recording system before overfishing occurs. One common mistake is waiting until populations are imperiled before creating management plans. This document discusses various methods for collecting fishery-dependent data, including catch estimates, catch disposition, catch per unit effort (CPUE), and fishing effort measures. It provides examples of calculating CPUE for different gear types like gill nets and longlines. The document also covers raising factors used to expand sample data to total population estimates.
Evaluation of the oyster farming potential of the Cintra bay (southern Morocco)Origins publication
The bay of Cintra is a marine ecosystem located in the southern Moroccan Atlantic known for its
biological richness and therefore for its high fishery productivity. This bay was chosen as a new destination for the
development of aquaculture in the southern regions of Morocco. To highlight its potential in terms of oyster
farming, a first rearing trial of triploid cupped oysters (Crassostrea gigas) as well as parallel monitoring of the
phytoplankton population and ecological parameters were undertaken. The results obtained showed that the oysters
adapt well to the conditions of the new environment where mortality was negligible, or even absent after a month
of launching. In terms of biological performance, the growth of individuals is continuous during the annual cycle
and after eight months the weight could reach 30.5 g which is a minimum weight for marketing. The AFNOR and
Lawrence and Scott indices showed a good physiological state and a better commercial quality of the oysters. The
filling rate of these oysters, with an average weight of 39.7g when lifting, is very high according to the Lawrence and
Scott index (126.3) and the average AFNOR index (around 21.8) rank them in the “Special” category.
The document discusses three potential solutions to challenges facing Ghana's artisanal fisheries:
1) Replacing illegal fishing nets, which would cost GHS 267 million but yield GHS 1.3 billion in benefits over 10 years.
2) Limiting fishing boats and providing training and subsidies for aquaculture, costing GHS 3.8 billion and earning GHS 4.5 billion in benefits.
3) Installing video devices on trawl vessels to reduce illegal practices, costing GHS 22.4 million initially and GHS 10.7 million annually, while increasing artisanal profits by GHS 260 million annually.
The Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docxmehek4
The Dynamics of an Open Access Fishery
Trond Bjørndal; Jon M. Conrad
The Canadian Journal of Economics / Revue canadienne d'Economique, Vol. 20, No. 1. (Feb.,
1987), pp. 74-85.
Stable URL:
http://links.jstor.org/sici?sici=0008-4085%28198702%2920%3A1%3C74%3ATDOAOA%3E2.0.CO%3B2-0
The Canadian Journal of Economics / Revue canadienne d'Economique is currently published by Canadian Economics
Association.
Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at
http://www.jstor.org/about/terms.html. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtained
prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in
the JSTOR archive only for your personal, non-commercial use.
Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained at
http://www.jstor.org/journals/cea.html.
Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printed
page of such transmission.
The JSTOR Archive is a trusted digital repository providing for long-term preservation and access to leading academic
journals and scholarly literature from around the world. The Archive is supported by libraries, scholarly societies, publishers,
and foundations. It is an initiative of JSTOR, a not-for-profit organization with a mission to help the scholarly community take
advantage of advances in technology. For more information regarding JSTOR, please contact [email protected]
http://www.jstor.org
Tue Jan 29 18:36:53 2008
http://links.jstor.org/sici?sici=0008-4085%28198702%2920%3A1%3C74%3ATDOAOA%3E2.0.CO%3B2-0
http://www.jstor.org/about/terms.html
http://www.jstor.org/journals/cea.html
The dynamics of an open access fishery
TROND BJBRNDAL Norwegian School of Economics
JON M. CONRAD Cornell University
Abstract. A discrete time non-linear deterministic model for an open access fishery is
developed and the equilibrium is characterized. The open access exploitation of North
Sea herring during the period 1963-77 is analysed. Alternative production functions are
considered and estimated for the Nonvegian purse seine fishery. The bionomic
equilibrium and approach dynamics are presented when prices and costs are changing.
The results indicate that the resource stock was saved from possible extinction by the
closure of the fishery at the end of the 1977 season.
Sur la dynumique d'une zone de pgches quund l'entrke est libre. Les auteurs developpent
un modele deterministe non-lineaire en temps discret d'une zone de p&ches ou l'entree
est libre et definissent les caracteristiques de l'equilibre. L'exploitation du hareng de la
Mer du Nord qui s'est faite sans entraves B l'entrte pendant la periode 1963-1977 est
analysee avec ce modele. Des fonctions de production de rechange sont examinees et
calibrkes pour la p&c ...
System design, sustainable production and water quality research for Recircul...IRJET Journal
This document summarizes a student project to design a three-stage water filtration system for a Recirculating Aquaculture System (RAS) to increase fish survival rates. The system includes a 1,000 liter culture tank stocked with 100 tilapia fish. Water flows through mechanical, biological, and UV filtration stages before being recirculated. The mechanical filter removes solid waste using various mesh screens and media. The biological filter uses biomedia like bio-ceramic rings to nitrify waste with the help of bacteria. Finally, the UV filter uses a quartz tube to disinfect water with UV light before recirculation. The design was optimized for factors like compactness, efficiency, cost-
Preliminary Report on Economic Valuation of Ecosystem Services of Guinea Curr...Iwl Pcu
Presentation from the focused learning discussion on economic valuation at the 4th GEF Biennial International Waters Conference.
Chidi Ibe
Guinea Current LME
Chika Ukwe
UNIDO
This document summarizes a study that used geographic information systems (GIS) to determine suitable areas for developing floating net cage aquaculture in Pelabuhan Ratu Bay, Indonesia. Water quality parameters were measured at locations throughout the bay from 2007-2008. The data was analyzed spatially using GIS to classify suitability. The results showed that 8,500 hectares (98% of the total area) were very suitable, 93 hectares were suitable, and 0.4 hectares were not suitable for floating net cage aquaculture. The water quality was found to be suitable for aquaculture based on comparisons to standards. The study concluded most of the bay is very suitable for developing floating net cage aquaculture and
Geographic information system application for determiningPrama Hartami
This document summarizes a study that used geographic information systems (GIS) to determine suitable areas for floating net cage aquaculture in Pelabuhan Ratu Bay, Indonesia. Spatial analysis of environmental and water quality parameters identified approximately 8,500 hectares, or 98% of the study area, as very suitable for net cage aquaculture. The analysis incorporated 12 biophysical variables and assigned scores to classify suitability. The results can help optimize sustainable aquaculture development and fishery production in the region.
This document summarizes a paper presented at an international conference on marine technology in Malaysia in 2012. The paper discusses quantifying greenhouse gas emissions from ships to support decision making and rulemaking by the International Maritime Organization. Specifically, it measures the concentrations of carbon dioxide and nitrogen dioxide emitted from a university research vessel during different operating modes to validate models for calculating emissions. Reducing greenhouse gas emissions from shipping is important because the industry accounts for a growing share of global emissions.
1. The team developed a project to improve fishermen's incomes by designing a new fishing boat and improving fishing gear and operations.
2. They identified factors affecting catch volumes like weather, crew skills, and finding fish. The team defined controllable and uncontrollable problem domains to systematically address issues.
3. Proposed solutions included designing a small-waterplane-area twin hull (SWATH) boat for safer operation in rough seas, developing forward fish detection, and mechanizing net handling to reduce labor. The project aims to benefit future research and develop Malaysia's fishing industry.
Bioeconomic analysis of marine fish production in west bengalAlexander Decker
This document summarizes a study on bioeconomic analysis of marine fish production in West Bengal, India. It aims to estimate maximum sustainable yield (MSY), maximum economic yield (MEY), and open access yield (OAY) for coastal fisheries in the region using historical catch data and a primary survey of costs and returns. The study applies Schaefer's surplus production model to estimate MSY from catch and effort data. It develops bioeconomic models to define MEY as the point where marginal revenue equals marginal cost, and OAY as the point where total revenue equals total costs, indicating zero profits. The results will inform policy suggestions to promote sustainable development and fisher welfare.
Using Systems Engineering Technology to Improve Efficiency of Small Oyster Fa...IRJET Journal
This document discusses using systems engineering techniques to improve the efficiency of small oyster farming operations in the Chesapeake Bay. It aims to develop and evaluate a process to enhance oyster farming through a systems approach. Class diagrams and a Python simulation model are developed to represent the oyster farming process from seedlings to market delivery. Timing data was collected from a small oyster farm to inform the models. The models can be used to analyze the farming system and identify potential bottlenecks or areas for improvement. The overall goal is to help small oyster farmers in the Chesapeake Bay optimize their practices and increase profitability.
Remotely sensed data of sea surface temperature, chlorophyll, and wind patterns from satellites are used to locate Potential Fish Zones (PFZ) in Indian seas. Satellites and instruments like sonar and radar are currently used to find areas where fish aggregate. In the past, PFZ forecasts were based solely on sea surface temperature maps, but now also incorporate ocean color data from sensors to provide information about conditions below the surface. The Potential Fishing Zone advisories generated from this remote sensing data have benefited fishermen in India by reducing search times, saving on fuel and labor, and increasing incomes.
Population dynamics of 15 fish species in Grand-Lahou lagoon (West Africa, Cô...Open Access Research Paper
This study described growth, mortality, recruitment patterns and exploitation rates of 15 fish species in Grand-Lahou lagoon (Côte d’Ivoire). Monthly length-frequency data collected from artisanal fisheries from November 2013 to October 2014 were analyzed with FiSAT software using the ELEFAN package to estimate the population parameters of fishes. Asymptotic values for total length (L∞) ranged from 15.75 cm for Synodontis schall to 59.80 cm for Trachinotus teraia. Growth rate (k) varied from 0.19 for Coptodon guineensis to 0.98 for Caranx hippos. The growth performance index estimates were close to the values found by other authors for most of the fish species. The total mortality (Z) high values were recorded for Synodontis schall (Z= 4.15 year-1; M = 2.50 year-1) Schilbe mandibularis (Z= 2.19 year-1; M=1.33 year-1). Fishing mortality (F) and exploitation rate (E) were found to be less than the optimum levels of exploitation for most fish species. The exploitation rate (E) was higher than the maximum sustainable yield (Emax) for Caranx hippos and higher than E0.5 for Eucinostomus melanopterus, Elops lacerta and Synodontis schall. Recruitment was noted as year-round and bimodal for most studied populations. These results demonstrate that some fish stocks necessitate effective management measures particularly C. hippos, E. melanopterus, E. lacerta and S. schall.
Mathematical models can help to better manage fishing - Encyclopedia of the E...TeXt10
Fishing provides an important part of the food for people in some developing countries. This can lead to a worrying cascade of overfishing, collapsing catches
and rising market prices, and the extinction of many species. How can we prevent this situation from becoming catastrophic and, on the contrary, stabilize it?
Mathematical modelling, by coupling ecological and economic dynamics, provides a better understanding of the dynamics of fisheries systems.
The International Journal of Engineering and Science (The IJES)theijes
This document analyzes sea wave transmission through mangrove forests of Rhizophora sp. in Indonesia. Measurements were taken in natural wave tanks constructed within the mangrove forest. Wave period, height, and transmission were measured using sensors. Porosity and transmission coefficients were calculated. Results showed transmission coefficients decreased with increasing wave steepness and porosity. The mangroves reduced wave heights by 57.73% at high porosity, demonstrating their ability to attenuate sea waves and protect the coastline from erosion.
Presentation about UNCLOS surplus concept in the frame of the EU Common Fisheries Policy to the Conference "Global Trends in Fisheries Governance" organized by the Swedish Agency for Marine and Water Management Rosenbad Conference Centre, Stockholm, 29–30 January 2014
Similar to Analysis of CPUE and Fishing Capacity of demersal fisheries in Kema 2, North Sulawesi, Indonesia (20)
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
Rainfall intensity duration frequency curve statistical analysis and modeling...bijceesjournal
Using data from 41 years in Patna’ India’ the study’s goal is to analyze the trends of how often it rains on a weekly, seasonal, and annual basis (1981−2020). First, utilizing the intensity-duration-frequency (IDF) curve and the relationship by statistically analyzing rainfall’ the historical rainfall data set for Patna’ India’ during a 41 year period (1981−2020), was evaluated for its quality. Changes in the hydrologic cycle as a result of increased greenhouse gas emissions are expected to induce variations in the intensity, length, and frequency of precipitation events. One strategy to lessen vulnerability is to quantify probable changes and adapt to them. Techniques such as log-normal, normal, and Gumbel are used (EV-I). Distributions were created with durations of 1, 2, 3, 6, and 24 h and return times of 2, 5, 10, 25, and 100 years. There were also mathematical correlations discovered between rainfall and recurrence interval.
Findings: Based on findings, the Gumbel approach produced the highest intensity values, whereas the other approaches produced values that were close to each other. The data indicates that 461.9 mm of rain fell during the monsoon season’s 301st week. However, it was found that the 29th week had the greatest average rainfall, 92.6 mm. With 952.6 mm on average, the monsoon season saw the highest rainfall. Calculations revealed that the yearly rainfall averaged 1171.1 mm. Using Weibull’s method, the study was subsequently expanded to examine rainfall distribution at different recurrence intervals of 2, 5, 10, and 25 years. Rainfall and recurrence interval mathematical correlations were also developed. Further regression analysis revealed that short wave irrigation, wind direction, wind speed, pressure, relative humidity, and temperature all had a substantial influence on rainfall.
Originality and value: The results of the rainfall IDF curves can provide useful information to policymakers in making appropriate decisions in managing and minimizing floods in the study area.