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1.
Abstract

The main objective of this study is to examine technical efficiency and its determinants in carp pond culture in Pakistan. A stochastic production frontier involving the model for technical inefficiency effects is applied separately to the samples of semi‐intensive/intensive and extensive carp producers. The mean technical efficiencies for semi‐intensive/intensive and extensive farms were 0.673 and 0.561, respectively. By operating at full technical efficiency the semi‐intensive/intensive farms could, on average, increase their production from 3.0 to 4.5 Mt/ha and the extensive farms from 2.6 to 4.6 Mt/ha. Much of these efficiency gains would come from the improvement in fish, water and feed monitoring and management. Besides improving technical efficiency, potential also exists for raising carp productivity through increased intensification and technological progress. However, the realization of these potentials will depend on continuous government support for adequate provision of inputs, market and infrastructure, technology transfer and development and extension and credit services to carp farmers.  相似文献   

2.
Abstract

We evaluate the profitability and technical efficiency of aquaculture in the Philippines. Farm‐level data are used to compare two production systems corresponding to the intensive monoculture of tilapia in freshwater ponds and the extensive polyculture of shrimps and fish in brackish water ponds. Both activities are very lucrative, with brackish water aquaculture achieving the higher level of profit per farm. Stochastic frontier production functions reveal that technical efficiency is low in brackish water aquaculture, with a mean of 53%, explained primarily by the operator's experience and by the frequency of his visits to the farm. In freshwater aquaculture, the farms achieve a mean efficiency level of 83%. The results suggest that the provision of extension services to brackish water fish farms might be a cost‐effective way of increasing production and productivity in that sector. By contrast, technological change will have to be the driving force of future productivity growth in freshwater aquaculture.  相似文献   

3.
This paper aims to examine the levels and determinants of technical efficiency in carp pond culture in India. The stochastic production frontier technique involving the model for technical inefficiency effects is applied separately to samples of semi‐intensive/intensive and extensive carp producers interviewed during 1994–95. The results showed significant technical inefficiencies in carp production in India, especially among extensive farms. The mean technical efficiencies for semi‐intensive/intensive and extensive sample farms were estimated to be 0.805 and 0.658 respectively. By operating at full technical efficiency levels, the semi‐intensive/intensive farms could, on average, increase their production from about 3.4 Mt ha?1 to 4.1 Mt ha?1. Likewise, the extensive farms could increase their production from 1.3 Mt ha?1 to 1.9 Mt ha?1. Much of these efficiency gains would come from improvement in the adoption of recommended fish, water and feed management and monitoring practices. Besides expanding production area, the results indicated several other possibilities for increasing carp production in India by increasing yields per hectare, such as: (1) increased intensification of carp culture (i.e. moving from extensive to semi‐intensive or intensive systems); (2) improvement in technical efficiency at the farm level; and (3) technological progress. However, the realization of these potentials will depend on continuous efforts by the government in ensuring an adequate supply of inputs, technology transfer and development and adequate provision of research, extension and credit services in aquaculture.  相似文献   

4.
This study aims to examine the technical efficiency of crucian carp polyculture systems in Jiangsu province, China, applying stochastic frontier analysis. Prior aquaculture polyculture studies using this method neglected the multi‐output nature of polyculture and aggregated all of the outputs into a single index. In this paper, we use a ray production function and adopt it in the stochastic front‐ier framework. Production functions defined as Cobb–Douglas and Translog specifications are both employed to compare cross‐sectional data collected for 144 farmers in 2012. The results reveal that the Translog specification captures the production behaviour and that there is an evident technical inefficiency in the polyculture setting. The mean technical efficiency is 79%. The farms that applied the new polyculture system demonstrate significantly greater efficiency on average than farms that applied the traditional polycult‐ure system. The output elasticity with respect to the polar coordinate angle θ1 is calculated to be 0.17. This represents a 0.17% increase in the output norm with a 1% increase in the output mix with fixed proportions between crucian carp and filter‐feeding fish. The output elasticity with respect to the polar coordinate angle θ2 is ?0.26. This represents a 0.26% decrease in the output norm due to a 1% increase in the output mix with the level of grass carp held constant. Hence, decision makers should be informed that the adopting of new species to the traditio‐nal system may be an effective way to unlock the productive potential of pond aquaculture in Jiangsu province.  相似文献   

5.
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   

6.
Abstract

A stochastic meta‐production frontier model is estimated to examine the inter‐country differences in levels of technical efficiency of semi‐intensive/intensive and extensive carp pond culture systems among the major carp producing countries in South Asia, namely India, Bangladesh, Pakistan, and Nepal. The mean technical efficiencies for semi‐intensive/intensive farms vary from 0.68 for Nepal to 0.79 for India, with an overall average of 0.75 and those for extensive farms vary from 0.48 for Bangladesh to 0.62 for Pakistan, with an overall mean of 0.57. Differences in efficiency levels are explained in terms of various farm‐specific and country‐specific factors by estimating a model for technical inefficiency effects. The adoption of recommended fish, water, and feed management practices is found to be critical for improved performance of carp producers. For each country, the study also compares the efficiency scores based on its own production frontier with those obtained from the meta‐production frontier.  相似文献   

7.
Milkfish has been farmed in Taiwan for over 300 years. Faced with limited land resources, a labor shortage, decreasing demand, and growth of imported fisheries products, the industry is looking at the problem of how to maintain a sustainable and efficient production. This study specifies a stochastic production frontier function to estimate potential milkfish farm output and efficiency by using 1997–1999 data from a survey of 433 aquaculture milkfish farms. Both Translog and Cobb–Douglas frontier production models are estimated using the maximum likelihood estimation method. Empirical results show that the Translog stochastic production function model fits the data better and that milkfish farming in Taiwan exhibits diminishing returns to scale. We also compare estimated maximum potential milkfish production per hectare under various pond conditions to provide managers with information about how to boost efficiency. In addition, this study estimates substitution elasticities and complementarity of input factors for milkfish farms to provide helpful information for milkfish farmers on how to reallocate input resources and help raise milkfish productivity through improvements in technical efficiency.  相似文献   

8.
Most research works on the production frontier in aquaculture focus on efficiency measurement using either Stochastic Production Frontier (SPF) or Data Envelopment Analysis (DEA). The studies on productivity growth in aquaculture were limited, perhaps due to lack of time-series data. Nevertheless, total factor productivity analysis (TFP) in fish farms has started gaining popularity in recent years. In addition, the majority of the efficiency studies have centered on technical efficiency analysis but substantial increases in the output levels can be fully realized through improving overall economic efficiency. Therefore, this review suggests that future research should estimate all three efficiency indices (i.e., technical, allocative and economic efficiencies).  相似文献   

9.
Polyculture is commonly practiced in pond aquaculture where several fish species are reared together, creating a multi-output production structure. This study applied a nonparametric data envelopment analysis (DEA) technique for multiple outputs to: (1) measure economic or ‘revenue' efficiency and its technical and allocative components for a sample of Chinese polyculture fish farms; and (2) derive the optimum stocking densities for different fish species. The mean economic efficiency was estimated to be 0.74. Technical inefficiencies accounted for most of the production inefficiencies in Chinese fish farms. On average, farmers should increase grass carp and decrease black carp stocking rates. Smaller farms and those from the developed regions were found to be relatively more technically and economically efficient.  相似文献   

10.
This paper presents the development of a simple and generally applicable hydrodynamic method for the estimation of production carrying capacity (PCC) of coastal finfish cage aquaculture. Dimensional analysis was used to find significant and general interdependencies between the hydrodynamics at fish farm locations and particulate wastes deposited on the seafloor by fish farms. Modeled ratios of deposition to emission of particulate wastes underneath fish farms were found to be primarily a function of the flow Reynolds numbers at the farming locations and the non-dimensional settling velocity of emitted wastes. In the non-dimensional model, farming conditions include daily feed rate, proportion of unconsumed feed, and carbon content in feed and fish feces. The relationship can be used to estimate the PCC of floating net cages imposing a threshold value for deposition. Results of in-situ assessments of the benthic impacts of several fish farms in an aquaculture site in the northwest of Bali, Indonesia were used to validate and demonstrate the effectiveness of the method. Predicted results were able to clearly identify fish farms operating beyond ecologically sustainable carrying capacity. The proposed method has broad applicability and could help make decisions regarding the estimation of production potential of individual farms in pristine areas, for providing first estimates in sites that have scarce data, and for assessment, expansion, and optimization of the currently operating aquaculture sites in Southeast Asia, China and potentially other data-poor island nations. As the method relies on dynamic models, it enables straightforward assessments over the entire aquaculture region.  相似文献   

11.
Abstract

Because Saudi Arabia is a substantial importer of fish and its capture fishery is operating beyond maximum sustainable limits, it has a special interest in developing fish farming. It has been encouraging tilapia production. This study examines the costs of tilapia farming in the Central Region of Saudi Arabia using cross sectional data from 23 intensive fish farms. It provides information about the relative importance of different cost items such as variable costs and feed costs in total costs. Also, cost functions are estimated by ordinary least squares and a cubic cost function is found to provide the best fit to the available data. Minimum average cost of production occurs for 201 tonnes of tilapia per year per farm and profit is maximised for a production of 300 tonnes annually per farm. All farms operate at less than profit‐maximising scale and most operate at less than minimum efficient scale. The reasons could be low quality fry, low levels of management expertise in culturing tilapia and the secondary nature of tilapia farming. Lack of water is likely to limit future expansion of tilapia farming in Saudi Arabia.  相似文献   

12.
Aquaculture is the world's fastest growing animal food producing sector. Although its overall performance is very good, it is unevenly spread geographically. In particular, the growth in most EU countries has been stagnating over the past 20 years despite repeated policy initiatives to launch new growth in the industry. The lack of production growth in EU aquaculture is often explained by strict environmental regulation and bureaucracy. In this article, we argue that an additional important element is an industry structure that limits the innovation and use of new technologies. Historically, farms have been small and often co‐managed with larger agriculture production. However, to succeed in a market with global competition, technological innovation and sector‐wide specialization, it is necessary to continuously increase productivity and induce investments in larger production facilities to take advantage of economies of scale. In Denmark, a structural change was ‘kicked off’ in 2005. In just 6 years, 30% of Danish production in freshwater has been reallocated to larger and more technologically advanced recirculation farms. Labour productivity has increased and the environmental impact per kilo of fish produced has been reduced, improving future prospects for aquaculture in Denmark and Europe.  相似文献   

13.
Sole is a high-value flatfish species that is highly favored in many European markets. Nowadays most sole comes from capture fisheries; however, wild supply has been decreasing because of decreasing catches due to stocks overexploitation. Due to its high price and declining landings, as well as a desire by farmers to diversify their operations, there has been an expansion in sole aquaculture production in recent years and there are ambitious plans for further growth. In this paper we assess the potential for sole aquaculture in Europe using raceways. This is done by analyzing the production costs of sole farms and the price evolution in European sole markets.  相似文献   

14.
Nitrogen removal techniques in aquaculture for a sustainable production   总被引：1，自引：0，他引：1  
As the aquaculture industry intensively develops, its environmental impact increases. Discharges from aquaculture deteriorate the receiving environment and the need for fishmeal and fish oil for fish feed production increases. Rotating biological contactors, trickling filters, bead filters and fluidized sand biofilters are conventionally used in intensive aquaculture systems to remove nitrogen from culture water. Besides these conventional water treatment systems, there are other possible modi operandi to recycle aquaculture water and simultaneously produce fish feed. These double-purpose techniques are the periphyton treatment technique, which is applicable to extensive systems, and the proteinaceous bio-flocs technology, which can be used in extensive as well as in intensive systems. In addition to maintenance of good water quality, both techniques provide an inexpensive feed source and a higher efficiency of nutrient conversion of feed. The bio-flocs technology has the advantage over the other techniques that it is relatively inexpensive; this makes it an economically viable approach for sustainable aquaculture.  相似文献   

15.
Abstract

A stochastic Cobb‐Douglas production frontier is used to provide estimates of output‐oriented technical efficiency, input‐oriented technical efficiency, input allocative efficiency and cost efficiency for a sample of seabass and seabream farms in Greece. Mean output‐oriented technical efficiency is estimated at 78.5%, input‐oriented technical efficiency at 73.6%, input allocative efficiency at 79.2%, and cost efficiency at 58.2%. Considering the sources of efficiency differentials among fish farms, it is evidence from the empirical results that large farms tend to achieve higher (technical and allocative) efficiency scores; specialization in either seabass or seabream affects positively technical and cost, but not allocative, efficiency; and utilization of skilled labor seems to have a positive impact only on technical efficiency.  相似文献   

16.
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   

17.
ABSTRACT

Thai koi farming is relatively new in the aquaculture industry of Bangladesh. Costly industrial feed pellets is the main factor influencing the productivity of Thai koi (Anabas testudineus). Two types of feed, namely, floating and sinking, are commercially available in the country. The ingredients of both types of feed are more or less the same. Floating feed requires high technology, high pressure and temperature and hence is more expensive than sinking feed. Most of the Thai koi farmers use either floating or sinking feed, while some farmers use a mix of both types of feed. This article investigated the effects of these three feed types on Thai koi productivity using primary data collected from the Mymensingh district of Bangladesh. The performance of different feed types on productivity was investigated using the Cobb-Douglas production function and propensity score matching (PSM) methods. Floating feed led to the highest daily mean weight gain of fish, feed conversion ratios, and net returns. The regression and PSM results revealed that farmers using floating feed produced significantly higher quantity of fish per unit compared to those using the other feed types. The cost of feed per hectare was higher in the farms using the floating feed, but these farms earned extra return from the additional investment, compared with the farms that use the other feed types. Thai koi farmers are advised to use floating feed to reap higher production and returns on investment.  相似文献   

18.
Despite the growing popularity of culture-based fisheries (CBFs) associated with village irrigation systems (VISs) in Sri Lanka, there is less knowledge about factors that influence productivity levels. CBFs compete with rice for access to water in the VIS, so maximizing the efficiency of CBFs is essential to ensure that the limited water resources are used most effectively. To address this, primary data from 325 fish farming groups were used to estimate a stochastic translog production frontier. Technical efficiency in these irrigation systems was found to be generally low, and substantially lower than that of other aquaculture production systems in other Asian countries. This suggests that production can be increased substantially with better management using existing technology and resources. Removing subsidies, improving consultation with extension officials and improving water user rights – in particular, the introduction of a transferable community quota system – were found to be key means for improving efficiency.  相似文献   

19.
Abstract

The objective was to evaluate the economic feasibility of introducing fish culture into irrigated cotton production on farms in central Arizona. Water as a production variable was calculated only for the additional quantity required to keep water in the ditches during the growing season for fish. Raising tilapia in pulsed‐flow culture systems on Arizona cotton farms is economically feasible. Production function estimates indicate that profits can be increased through additional use of feed. At any ditch capacity, a density of six fish/m3 provided the optimal economic results, as the value of marginal product (VMP) equalled the price of fingerlings stocked/m3. This optimum fish production scenario would increase the net income for a typical irrigated cotton farm by 7 per cent. Increasing the initial size of the fingerlings improved the percentage of fish reaching marketable size and perhaps will increase economic returns, a question to be studied by future research.  相似文献   

20.
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   

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