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1.
Abstract

This paper examines recent advances in production economics with special reference to efficiency measurement using production frontiers and its implications for aquaculture management. Compared with agriculture and other industries, the use of production frontiers in aquaculture is still very limited. However, in recent years several frontier applications in aquaculture have appeared in the literature, suggesting potential applications of these techniques in aquaculture. A synopsis of stochastic frontier production function model and data envelopment analysis (DEA), the two most popular approaches to efficiency measurement, is presented, followed by a review of recent frontier studies in shrimp, carp and tilapia production. The paper concludes with a brief discussion of future development and prospects of frontier applications for aquaculture management.  相似文献   

2.
ABSTRACT

Asian aquaculture has been contributing in great measure to the global fish basket. The Indian subcontinent, with a rich biodiversity of fish species, has emerged as an important aquaculture country, particularly in the freshwater environment. Carps form the mainstay of culture practices in the country, supported by a strong traditional knowledge base and scientific input in various aspects of biology, environment, nutrition, and health management. New species and culture systems, integration with other farming systems, use of organic material as nutrient inputs, and depuration measures in waste-fed culture systems are being considered for enhancing aquaculture productivity. This article presents the status of grow-out production of carps in India and traces the growth of the practices over the decades as well as the potential of the sector.  相似文献   

3.
Abstract

The recent advances in information technology (IT) have had profound impacts on all walks of life and aquaculture is no exception. The growing importance of aquaculture as an alternative source of protein has further emphasized the need to adapt and develop advanced IT for the better management of aquaculture facilities as well as the regional planning for aquaculture development.

It is the objective of this paper to review the use and potential prospects of IT in aquaculture management. The information technologies considered are instrumentation and process control, data management, computerized models, decision support systems, artificial intelligence and expert systems, image processing and pattern recognition, geographical information systems, and information centres and networks. The review includes a brief introduction of each of the aforementioned technologies, followed by a survey of their current application as well as their potential use in aquaculture management.  相似文献   

4.
Abstract

The notable increase of aquaculture production in recent decades has in many instances been matched by growing concern for its impacts. Environmentalists, consumers and members of the general public are increasingly demanding to account for its resource use and to balance its proposed benefits with its environmental sustainability. Although conventional financial and economic analyses have demonstrated a broadly positive impact for many forms of aquaculture, including the more intensive resource‐demanding systems, the use of economic tools embracing wider measurements of social and environmental costs and benefits might provide different and possibly more critical perspectives. However, although these techniques hold promise for such analyses, their development and application in sectors such as aquaculture are as yet limited. This paper reviews the relevant issues, considers the tools and applications of environmental economics and proposes ways in which these may be more effectively be applied in strategic and local decision‐making for aquaculture development.  相似文献   

5.
Abstract

Puerto Rico has been faced with a decline of fish stocks similar to other parts of the world. Offshore cage aquaculture might be an answer to this problem although there are many unanswered questions. This paper describes a project in Puerto Rico that assessed the economics of offshore cage culture for aquaculture. The first cage was placed in the water in February 2002 with a second one to follow shortly thereafter.  相似文献   

6.
ABSTRACT

In India, inland aquaculture has emerged as a fast-growing enterprise and a viable alternative to the declining capture fisheries. The present paper is an attempt to assess Indian inland aquaculture with respect to its resource base, output trends, systems and activities, yield gaps, adoption and impact on aquaculturists, economics, returns to inputs, investment needs, and future prospects. The paper is largely based on existing literature and observations made as part of an ICAR-WorldFish demand supply project. Indian aquaculture is primarily limited to inland sector and carp-oriented; for that reason, this activity received special attention. Freshwater aquaculture observed tremendous growth in the past 15 years, but immense scope still exists for horizontal expansion and increases in productivity (vertical expansion). This is evidenced by the fact that the average farm fish yield is only one-third of that achieved in farm trials. The difference was mainly due to much higher input use in on-farm trials. Most of the aquaculturists were practicing extensive aquaculture, but aquaculturists with semi-intensive operations benefited most from adoption of technology. The benefit:cost ratios for different systems of aquaculture varied between 1.22 to 1.86. The return to capital was much higher than the return to labor, due to the low labor input. The semi-intensive aquaculture system would receive the greatest return from projected macrolevel investments, followed by extensive and intensive systems. Dedicated efforts are needed to meet the demand for quality fish seed and feed in order to achieve the desired 45% increase in area and greater than 50% increase in productivity. Based on the observations, activities designed to foster inland aquacultural development in India are recommended.  相似文献   

7.
Abstract

Designing intelligent management strategies for shrimp aquaculture systems require recognising the uncertainty and risks associated with different processes of aquaculture production. To account for natural variability and other sources of uncertainty, estimates of appropriate aquaculture bio‐economic indicators are needed to re‐evaluate periodically the production system and establish new reference points and corresponding management strategies. This paper concentrates on this aspect of the management process and presents a simple classification of indicators and reference points for aquaculture production systems. The uncertainty causing variability in the estimated values of bio‐economic parameters is incorporated through the use of Monte Carlo analysis to estimate the probability of exceeding limit reference points. To illustrate this process, the risks (i.e. probabilities of exceeding bioeconomic limit reference points) associated to alternative timing of harvesting decisions were estimated by randomly generating uncertain prices and natural mortalities with the appropriate probability density functions and corresponding variance. Alternative approaches to deal with risk and uncertainty in data limited management contexts are discussed.  相似文献   

8.
Abstract

The Partitioned Aquaculture System (PAS) provides a promising intensive aquaculture technology that is efficient and profitable, while simultaneously solving a variety of culture problems. This creates a sustainable aquaculture technology, which is environmentally safe and economically feasible. The PAS eliminates water discharge and reduces land usage and ground water requirements.

The PAS system production process was modeled for catfish production using a growth model developed from observed data. The results of the PAS economic analysis were compared with two traditional catfish production scenarios. Comparisons were made between estimated investment requirements, operating costs and internal rates of return and breakeven points for alternate production systems and land ownership status. The results look promising, but research is ongoing on how best to manage the filter feeder component of the PAS.  相似文献   

9.
ABSTRACT

The paper reviews freshwater and coastal aquaculture practices in Thailand, and compares the productivity, costs, and benefits across various types of cultivation and various intensities of production. The paper is based on data that were collected in surveys conducted during 1998–2001 by the Department of Fisheries (DOF), Thailand and the WorldFish Center. More than 22% of Thailand's fish supply comes from aquaculture, with coastal aquaculture accounting for more than 88% of this in terms of value. Intensive culture of shrimp is the dominant form of coastal aquaculture, occupying 69% of the area under production. However, in some regions, the average net profit/kg of intensive shrimp culture is negative, and semi-intensive farming, with relatively lower fixed investment and operating costs, delivers the highest rate of return on investment. On the coast, grouper and sea bass are the most important cage-cultivated species, achieving an economic rate of return as high as 92%. In the same environment, culture of mollusks, such as green mussels, oysters, and blood cockles, is widespread. It can also be economically sustainable, with relatively low capital and operating costs. Although the relative share of freshwater aquaculture production is declining, the level of output has been increasing rapidly. While the average production from monoculture of carnivorous species is higher than that from polyculture, the average capital investment and operating costs associated with the former are also higher. The expansion of freshwater polyculture and of mollusk culture in coastal areas would greatly assist poor fish farmers.  相似文献   

10.
Abstract

The environmental costs associated with coastal aquaculture, though poorly understood, can in some cases be quite large. The presence of risk, uncertainty and insufficient monitoring can greatly reduce the power of traditional economic instruments such as environmental taxes and tradable permit systems to internalize these costs. Using the Texas shrimp farming industry as a specific example, this article explores the potential of environmental assurance bonds (EABs) as an alternative economic instrument to internalize environmental costs of aquaculture production under such conditions. Drawing from previous literature, an explicit distinction is made between two mechanisms simultaneously incorporated in the EAB: a deposit‐refund incentive and social insurance. The article discusses the role of each of these mechanisms in shifting the environmental costs of production back to firm. Practical application of EABs in the Texas coastal shrimp farming industry is then examined.  相似文献   

11.
Abstract

A production management and planning system has been developed for large‐scale hanging culture operations. The relational database was designed to provide a fast, reliable and versatile tool for managing large volumes of production data at a scallop aquaculture site. The application development process is described, starting with the set of management decisions to be supported by the software. Best practices used for data structure design included normalization and entity‐relationship diagramming. The process‐based design resulted in visually consistent and user‐friendly interfaces which minimize data entry errors. An integrated forecasting model, based on seasonal exponential smoothing, extrapolates stagewise mortalities and flows calculated from the database. Typical simulation results demonstrate how forecasts provide insight into the grow‐out dynamics for capacity planning, manpower planning, and dealing with seasonal fluctuations in the yields. The software generates daily production reports, weekly harvesting schedules and long‐range planning information.  相似文献   

12.
Abstract

Although aquaculture in Egypt has the potential for satisfying the increased demand for protein and has been experiencing unprecedented growth during the last decade, questions remain regarding the sustainable development of the industry. It is thus the objective of this article to review the current status and practices of the aquaculture industry in Egypt, highlighting the major issues confronting the sustainable development of the aquaculture industry.

Several issues are identified as limitations to future sustainable development, namely, production technology, fry supply, a feed industry sufficient to meet the demands of a growing aquaculture industry, and marketing and distribution systems necessary to accommodate the strong seasonal supply pattern. The article then concludes with a discussion of recommendations for alleviating these limitations.  相似文献   

13.
Abstract

This paper uses a linear programming model to examine the economic viability of four fish production strategies in the context of rainfed farming systems in the north‐eastern region of Thailand. The four systems are rice bran feeding system, pond fertilization using buffalo manure, fish production recommendations developed by the Asian Institute of Technology (AIT) Recommendations and an integrated duck/fish production system. These systems have been introduced into North‐eastern Thailand where the main obstacles to fish production are the lack of indigenous knowledge offish culture and a shortage of water. While technical feasibility studies are needed to evaluate the practical viability of aquaculture technologies, economic assessment is required to assess their commercial viability. The objective of this paper is to examine whether or not these fish production systems can contribute to, and integrate with, the prevailing farm system in the North‐east of Thailand. The linear programming model is used to determine the optimum on farm product mix that maximizes net returns under each of the four production systems. Among different resources, labour requirement in the fish‐stocking month appeared to be the first binding resource, while capital requirement was not a constraint for an average farming household of the region. A sensitivity analysis is presented to show how each of the fish production systems operates with different levels of pond size, labour and capital availability. The results of the study show that these aquaculture systems are economically attractive and can contribute significantly to the livelihood of the small‐scale farmers of North‐east Thailand.  相似文献   

14.
ABSTRACT

Over 71% of the aquaculture production of Chile is based on salmonids, and given the recents problems in the world salmon industry, it is necessary to investigate the culture of new species as a vital priority to maintain an industry of great social and economic impact for Chile. Small-eye flounder, Paralichthys microps, and chilean flounder P. adspersus, are native, high-value flatfish present off the coasts of Perú and Chile, that are commonly exploted by artisanal fishermen. Since 1986 both species have been objects of research studies for culture based on techniques developed for Japanese flounder. This paper is a review of current knowledge of this species and to identify research needs for the near future. Natural spawning of small-eye flounder and chilean flounder broodstock in captivity is already possible, but the manipulation of spawning using photoperiod and hormonal inducement, as well as the role of broodstock nutrition in egg and larval quality, needs to be explored. Successful incubation and larval culture protocol for both species have been developed, with larval survival over 24% from certain egg batches. Nutritional characterization and requirements for chilean flounder eggs and larvae during the culture period, optimal temperature, density, light intensity and green-water culture, are all subjects of ongoing research. Efforts to improve early culture protocol continues with emphasis on causes of larval mortality, early use of dry feed, microbial ecology of culture tanks and water quality. Weaning from live to formulated diets has been investigated, demonstrating survival of 30-50%. Presently only about 1-5% of hatchery raised flounder show a pigment disorder. Research on formulated diets and the weaning process are under way to ameliorate these results. Juveniles are being grown experimental in tanks and net pens systems and their performance (growth, survival, health) in both systems is being evaluated. Chilean flounder require approximately 2.8 years to reach 1 kg. Effort is also focusing on improving juvenile growing protocol, including recirculation systems, culture environment and diet formulation. Much future research will be required to attain optimal production of the species, such as species-specific nutritional requirements, optimum stocking density, disease and health management and growing protocols with new systems (shallow raceway). At present there is enough known about chilean flounder to begin a pilot-stage that will be the key for future development of its culture.  相似文献   

15.
Abstract

Nutrient availability is considered to have a major role in controlling primary productivity. Therefore, an important aspect of successful aquaculture management in fish culture systems is making available basic nutrients, for example, phosphorous (P), nitrogen (N), and carbon (C) in optimal concentrations. The use of fertilizers in relation to pond productivity has been studied in order to develop better fertilization procedures under given environmental conditions. Many researchers from across the world have suggested different N:P ratios for optimizing fish production. The primary aim of this study was to understand the influence of nutrient quality and quantity on fish and primary productivity in terms of optimizing fish production. Two objectives of this study include evaluating the performance of pig and cow manures in terms of primary productivity and fish production; and understanding the influence of different N concentrations ranging from 1-2 ppm on fish production while P was maintained at 0.5 ppm. It was evident from this research that fish species nutrient-sensitivity to nitrogen concentrations ranging from 1-2 ppm was significantly different. The 1 ppm N:0.5 ppm P concentration was found to be the most suitable nutrient ratio for pond fertilization as significantly higher fish production and lower mortality were recorded in this treatment. In terms of plankton and fish production, pig manure was found to be significantly more effective than cow manure. Higher nutrient (>1 ppm N) concentrations negatively impacted zoo-plankton and zoo benthos development. Daily manure application would considerably reduce the organic load in the fish culture system, enabling more efficient use of nutrients for primary and secondary production.  相似文献   

16.
ABSTRACT

The control and management of production factors have been of great economic interest for the aquaculture industry. In this study, the optimal harvesting time that maximizes the net benefits of shrimp cultured in freshwater was determined using a bioeconomic model fitted to six stocking density strategies (90, 130, 180, 230, 280 and 330 shrimp m?2). A model was constructed which included the size heterogeneity of the culture and the results obtained were compared with the traditional model which assumes size homogeneity for all individuals. The results from both models indicated that the stocking density of 90 shrimp m?2 was the best management strategy for optimizing net benefits. The economic importance of taking into account size heterogeneity in the culture of the white shrimp in freshwater is discussed.  相似文献   

17.
The annual increase in farmed freshwater prawn production in the world during the decade ending 2001 has been estimated as 29% and that during 1999–2001 as 48%, the production in 2001 being about 300 000 mt (all Macrobrachium species). Between 1999 and 2003 the annual increase in farmed Macrobrachium rosenbergii production in India was about 80%, production reaching 30 450 mt in 2002–2003. This log phase of production followed the rise and fall of shrimp farming in the country. Several shrimp farming ventures collapsed in the 1990s, owing to degraded environment and diseases, abetted by lack of awareness and inadequacy of information on the culture systems and their interactions with other human endeavours. This shrimp farming experience has made the aquafarmer and other stakeholders aware that while aquaculture has a high potential in ensuring food and nutritional security and livelihood, besides profit to the farmer and socio‐economic benefits to local communities, it is likely to slip from sustainable development pathways if adequate understanding, improved management practices, governmental policies and plans for implementation and regulation to ensure sustainability are not in place. The lessons learned from shrimp farming can help in steering the development of sustainable freshwater prawn aquaculture in India and elsewhere.  相似文献   

18.
Silver perch, Bidyanus bidyanus (Mitchell), is a freshwater fish that is endemic to the Murray‐Darling River System, Australia. Over recent decades, its distribution and abundance in the wild have declined, and it is now a threatened species with the conservation status of “vulnerable.” Silver perch is a schooling, omnivorous fish, with white flesh, few bones, and high levels of omega fatty acids, and its aquaculture potential has long been recognized. Hatchery techniques, based on hormone‐induced spawning of captive broodfish in tanks and rearing of larvae in fertilized earthen ponds, were developed in the early 1980s. Fingerlings are currently used for stock enhancement and conservation or sold for commercial grow‐out or stocking farm dams. Research into the grow‐out of silver perch commenced in 1990 and demonstrated that it is an excellent fish for culture in static aerated earthen ponds with high survival rates (>90%), fast growth rates (2–5 g/fish/d) at high stocking densities (20,000/ha) leading to high production rates (10 tonnes/ha/yr). Since 1996, there has been research into nutrition, diet development, feeding strategies, broodfish domestication and management, culture in tanks and tank‐based recirculating aquaculture systems, diseases, health management, genetic improvement, and cage culture. Silver perch is a hardy species that performs well under different culture conditions and on diets with no or low levels of fish meal. Technology has been transferred to industry through major conferences in 1994 and 2003 as well as workshops, field days, extension, seminars, and numerous scientific and technical publications. The high quality of silver perch and its excellent culture attributes suggest that the species has the potential to form a large industry based on high‐volume, low‐cost production. However, despite these features and a strong technical base provided by research and development, industry growth has been limited and a relatively small industry currently produces only around 500 tonnes annually. Development has been restricted by a number of factors: poor site selection and design of some farms; use of inappropriate husbandry and/or production strategies; difficulties with pond production, including significant losses to bird predation and diseases; high costs of feeds; limited marketing and promotion; no processing component; no large‐scale investment; and the failure of many farms that were too small to be economically viable. Recent research has found that silver perch performs well in cages (high survival [>90%], good growth [1.7–3.5 g/fish/d], and high production rates [50–90 kg/m3]), and cage culture has advantages such as ease of management and prevention of bird predation that may help overcome some of the problems associated with pond production. Improved health management, new production strategies, cage culture, use of interstrain hybrids and other genetically improved fish, and integration with cotton and other irrigation industries offer opportunities for increased production and efficiencies, and further development of the silver perch industry. The potential of silver perch for commercial aquaculture remains very high.  相似文献   

19.
Abstract

Modern aquaculture is a relatively new activity among Nepalese farmers and a small contributor to the economy. Given the abundance of water resources and fish species, rising demand for fish, and its high profitability, aquaculture has potential for future expansion if it is given appropriate attention from the government. In Nepal, productivity in aquaculture is much lower compared to other countries in the region, which suggests that there is potential for increased fish production through technological progress and improvement in farm‐level technical efficiency. However, no formal analysis has yet been conducted to assess the productive performance of Nepalese aquaculture and its potential for future improvement. Against this background, this paper examines the technical efficiency and its determinants for a sample of fish pond farms from the Tarai region of the country using a stochastic production frontier involving a model for technical inefficiency effects. The estimated mean technical efficiency is 77%, with intensive farms being more efficient than extensive farms. The adoption of regular fish, water, and feed management activities has a strong positive effect on technical efficiency.  相似文献   

20.
Farming of the striped catfish, Pangasianodon hypophthalmus, is a major aquaculture activity in Bangladesh, particularly in the district of Mymensingh. However, pangasius farm management practices and the socio‐economic impacts of pangasius farming systems in Mymensingh have not yet been adequately described in the literature. This article provides an overview of the present status and characteristics of pangasius culture in Bangladesh based on data from a study conducted in Mymensingh district during 2009. The mean productivity of pangasius was 36.9 MT ha?1, where 87.9% of the farms produced between 15 and 65 MT ha?1 of pangasius, with an additional 10–20% Indian major and Chinese carps and Nile tilapia. Pangasius aquaculture in Bangladesh has improved the economic and social status of a variety of stakeholders in communities where the fish is farmed.  相似文献   

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