Regional and global trends in aquaculture production, value and price are assessed for the last 30 years relative to trends in wild caught species. Based on data from the Fisheries and Aquaculture Department of the Food and Agriculture Organization of the United Nations for aquaculture production, data is extracted for the first time to address regional (Europe, North America, South America, Africa, Oceania and Asia) trends in production focused on the top five aquaculture produced species. Previous uses of the database have largely focused on global production. Of the top five species (whiteleg shrimp Penaeus vannamei, Atlantic salmon Salmo salar, silver carp Hypophthalmichthys molitrix, common carp Cyprinus carpio, and giant tiger prawn Penaeus monodon), Asia accounts for most of the global production (with the exception of Atlantic salmon Salmo salar). The central issue considered in this thesis concerns the likelihood and capacity of aquaculture production of fish and shellfish protein for human consumption relative to that of exploited wild stocks. Over the last 30 years or so, aquaculture production has risen exponentially and captures of wild caught fish have now plateaued. The relative status, rearing practices, production and basic economic perspectives of the principle aquaculture produced species globally are compared with wild caught production. The principle finding is that total global aquaculture production will exceed that of commercial wild caught species by about 2015. The significance of this is discussed in terms of current views of environmental (e.g. pollution, disease and habitat degradation) and economic (e.g. production level, farm price, marketing economics, fixed costs (facility and equipment depreciation, loan interest, land lease, fixed wages), variable costs (cost of seed stock, feed, energy)) impacts of aquaculture. Similarly, these issues are considered for the fishing industry (e.g. fishing down the food web, likelihood of expansion of bottom fisheries into deeper waters, reduction of biodiversity, declining global catches). It is concluded that aquaculture is a necessity and that if current trends continue aquaculture production can more than supplement human fish protein needs even in the given context of the rapid growing population, but that in the long term aquaculture production will itself be substantially supplemented by “rebounding” wild fishery production.

Regional and global trends in aquaculture production, value and price are assessed for the last 30 years relative to trends in wild caught species. Based on data from the Fisheries and Aquaculture Department of the Food and Agriculture Organization of the United Nations for aquaculture production, data is extracted for the first time to address regional (Europe, North America, South America, Africa, Oceania and Asia) trends in production focused on the top five aquaculture produced species. Previous uses of the database have largely focused on global production. Of the top five species (whiteleg shrimp Penaeus vannamei, Atlantic salmon Salmo salar, silver carp Hypophthalmichthys molitrix, common carp Cyprinus carpio, and giant tiger prawn Penaeus monodon), Asia accounts for most of the global production (with the exception of Atlantic salmon Salmo salar). The central issue considered in this thesis concerns the likelihood and capacity of aquaculture production of fish and shellfish protein for human consumption relative to that of exploited wild stocks. Over the last 30 years or so, aquaculture production has risen exponentially and captures of wild caught fish have now plateaued. The relative status, rearing practices, production and basic economic perspectives of the principle aquaculture produced species globally are compared with wild caught production. The principle finding is that total global aquaculture production will exceed that of commercial wild caught species by about 2015. The significance of this is discussed in terms of current views of environmental (e.g. pollution, disease and habitat degradation) and economic (e.g. production level, farm price, marketing economics, fixed costs (facility and equipment depreciation, loan interest, land lease, fixed wages), variable costs (cost of seed stock, feed, energy)) impacts of aquaculture. Similarly, these issues are considered for the fishing industry (e.g. fishing down the food web, likelihood of expansion of bottom fisheries into deeper waters, reduction of biodiversity, declining global catches). It is concluded that aquaculture is a necessity and that if current trends continue aquaculture production can more than supplement human fish protein needs even in the given context of the rapid growing population, but that in the long term aquaculture production will itself be substantially supplemented by “rebounding” wild fishery production.

Regional and global trends in aquaculture production, value and price are assessed for the last 30 years relative to trends in wild caught species. Based on data from the Fisheries and Aquaculture Department of the Food and Agriculture Organization of the United Nations for aquaculture production, data is extracted for the first time to address regional (Europe, North America, South America, Africa, Oceania and Asia) trends in production focused on the top five aquaculture produced species. Previous uses of the database have largely focused on global production. Of the top five species (whiteleg shrimp Penaeus vannamei, Atlantic salmon Salmo salar, silver carp Hypophthalmichthys molitrix, common carp Cyprinus carpio, and giant tiger prawn Penaeus monodon), Asia accounts for most of the global production (with the exception of Atlantic salmon Salmo salar). The central issue considered in this thesis concerns the likelihood and capacity of aquaculture production of fish and shellfish protein for human consumption relative to that of exploited wild stocks. Over the last 30 years or so, aquaculture production has risen exponentially and captures of wild caught fish have now plateaued. The relative status, rearing practices, production and basic economic perspectives of the principle aquaculture produced species globally are compared with wild caught production. The principle finding is that total global aquaculture production will exceed that of commercial wild caught species by about 2015. The significance of this is discussed in terms of current views of environmental (e.g. pollution, disease and habitat degradation) and economic (e.g. production level, farm price, marketing economics, fixed costs (facility and equipment depreciation, loan interest, land lease, fixed wages), variable costs (cost of seed stock, feed, energy)) impacts of aquaculture. Similarly, these issues are considered for the fishing industry (e.g. fishing down the food web, likelihood of expansion of bottom fisheries into deeper waters, reduction of biodiversity, declining global catches). It is concluded that aquaculture is a necessity and that if current trends continue aquaculture production can more than supplement human fish protein needs even in the given context of the rapid growing population, but that in the long term aquaculture production will itself be substantially supplemented by “rebounding” wild fishery production. / Science, Faculty of / Resources, Environment and Sustainability (IRES), Institute for / Graduate

Increased domestic and international demand for aquatic foods have greatly enhanced aquaculture practices and production in Bangladesh, which is reflected in the national economy. However, the impacts of a fast growing aquaculture sector through the involvement of stakeholders, poorer sections throughout the value chain and broader rural livelihoods are largely underdeveloped and have frequently been ignored. The present study explores the impacts of dynamic aquaculture sector on stakeholders at production level and supply chain and test the hypothesis that aquaculture is enhancing rural livelihoods and benefiting the poor. Three aquaculture production systems in three areas of Bangladesh were selected for the study. These were prawn production in gher system in Jessore, pond fish culture in Mymensingh and rice-fish farming in Dinajpur. This selection allowed analysis both the impacts of domestic and export marketing of aquaculture products. Participatory research data collection tools; focus group discussions and participatory mapping were commonly used along with questionnaire surveys to ensure participation of stakeholders. Aquaculture, in general, found to have had significant impacts on rural livelihoods. The greatest effect of aquaculture on farming households were observed in income and consumption. Integrated aquaculture systems were the regular source of fish and vegetables and constitute more than half of the fish and vegetables consumed by farming households. While income from aquaculture was the highest among the several household income sources, the main cash crop differed between the systems studied. Prawn, fish and rice was the main cash earning crops for gher farming, fish farming and rice-fish farming respectively. Qualitative investigation suggested that aquaculture not only increased income through greater production volume, but also improved farmers’ assets through income diversification to farm and non-farm sources. The other important outcomes of aquaculture were the enhancement of social safety nets through increased sharing of inputs and labour among farmers. Commonly the aquaculture systems were found to be more intensive with an increasingly commercial attitude over the last ten years, which affected the intra-household labour distribution leading to a greater role for women in production management. While the three activities; fish feed preparation, feeding and growing vegetables performed by vast majority of women could be attributed to their inherent involvement with agriculture, hard physical work like harvesting ponds and pond construction were mostly carried out by the women from poor households as a strategy to reduce hired labour cost. The women’s’ increased involvement in aquaculture not only increased their overall workload, but also empowered them in household decision making to some extend. However, involvement in decision making was related to the level of involvement in production activities. The impacts of aquaculture spread beyond the farming households to the broader rural livelihoods. Wage labourers and fishers (harvesting teams) two of the poorest groups of people directly involved were benefited most over the last ten years. Intensification of aquaculture increased the demand for hired labour leading to a structural shift in the agricultural wage labour market in farming communities. About half of the agricultural labourers were found part-time employed in aquaculture activities in Jessore and Mymensingh. In Dinajpur intensification of rice cultivation had a much higher effect on the demand for labour than aquaculture. Increased employment in rural areas increased real labour wages by about one fifth over the last ten years and subsequently improved livelihood outcomes. Declining fish catch due to both decreased natural fish stocks and more restricted property rights, professional fishers benefited by diversifying their livelihoods into the aquaculture sector. While, many of the fishers permanently changed their profession to prawn marketing in Jessore, the rest were full-time or part-time employed in harvesting ponds and/or retailing fish in markets. Such diversification of income greatly reduced seasonal vulnerability and improved livelihood outcomes. The role of fish marketing, which is a critical institution in rural livelihoods, was found to facilitate the growth of the aquaculture sector. High demand of aquatic products and the diverse options of marketing fisheries enabled farmers to meet their initial requirements. More commercial operations of aquaculture increased farmers’ awareness and linkages to markets. However, typically the worse-off farmers were the slowest to capture new market opportunities, often due to their poor resources and human capital. Fish marketing was found to be run by the private sector and government provided the infrastructure facilities, except prawn processing plants, which were developed by private sector. While the fish market transactions were fairly efficient, markets facilities and infrastructure were commonly poor and need of government investment for improvement. A gradual growth of fish and markets in the rural areas was observed in the study; this was driven by the increased demand for fish through increased population and supply from aquaculture. The marketing intermediaries provided important services despite their small share of consumers’ price and ensured a fair share for farmers. The auctioneers provided a vital role in running the supply chain with investment and credits, which ensured fair competition in the pricing process. Marketing of aquatic products was not only a mechanism of product transaction, but also provided critical livelihoods for rural poor. On average about one hundred people, including retailers were involved in auction markets and eight people in prawn depots. Importantly the number of people in marketing was found to have increase over the years. Access for different groups of poor people to marketing jobs was found to be significant in rural livelihoods. The asset base and daily earning indicates that more than three quarters of the marketing intermediaries were poor; some of them were from poorest and low cast Hindu society. Greater flexibility of entry and exit to the jobs enabled the poorer sections to diversify their livelihoods, which enabled to cope with seasonal variability of opportunities and stable income. The marketing employment provided then increased livelihood welfare and social security. Finally, it can be concluded that the promotion of aquaculture not only increased much needed food availability but also generated critical livelihoods and marketing is not just a mechanism of product flow, but also providing livelihoods welfare to poorest sections of the society. The micro level findings of the study regarding impacts of aquaculture indicate that aquaculture production and marketing have significant impacts on enhancing rural livelihoods in Bangladesh.

No description available.

Commercial farming of mud crab Scylla serrata is a significant industry throughout South East Asia. The limited scientific knowledge of mud crab nutritional requirements and digestive processes, however, is recognised as a major constraint to the future growth of this industry. To better understand the mechanisms of digestion in the mud crab we have analysed the diversity of digestive enzymes from the hepatopancreas. Significant protease, amylase,cellulase and xylanase activities were detected in soluble extracts from this organ. Temperature profiles for all enzymes were basically similar with optimal activities observed at 500C. Examination of pH tolerance revealed optimal activities for protease and amylase at pH 7.0 while optimal activities for cellulase and xylanase were observed at pH 5.5. Under optimum conditions,protease and amylase activities were approximately two orders of magnitude greater than those seen for either cellulase or xylanase. Interestingly, hepatopancreatic extracts were able to liberate glucose from either starch or carboxymethyl (CM)-cellulose suggesting that a range of carbohydrates may be utilised as energy sources. The effects of dietary carbohydrates on feed digestibility, digestive enzyme levels and growth were also studied by inclusion of additional starch or CM-cellulose at the expense of casein in formulated diets. It was shown that amylase, cellulase and xylanase activities in extracts from the hepatopancreas were highest in mud crabs fed diets containing 47% carbohydrate. Based on the findings, we suggest that the ability of the mud crab to modulate digestive enzyme activities may represent a mechanism to maximise access to essential nutrients when the dietary profile changes.

Research developing artificial propagation, husbandry, and nutrition of sturgeon species has developed greatly since the collapse of the Caspian Sea fisheries in the 1980s. Sturgeon species are commercially prized for their unfertilized roe which is marketed as the delicacy, caviar. Sturgeon production units commonly utilize commercial salmonid feeds, which contain large proportions of fish meal (FM) and fish oil (FO). Concerns regarding economics and sustainability have put pressure on aquafeed manufactures to efficiently utilize FM and FO, and to incorporate alternative protein sources, such as soybean meal (SBM). Therefore, the present studies estimated the optimal protein:energy ratio of juvenile Pallid Sturgeon Scaphirhynchus albus and evaluated the effects of increasing SBM composition on growth, feed efficiency, body and liver composition, and intestinal morphology of juvenile Shovelnose Sturgeon Scaphirhynchus platorhynchus, two species of Scaphirhynchus sturgeon of regional commercial importance. Protein:energy ratios were investigated using casein and dextrose based, semi-purified diets. Results indicated that Scaphirhynchus sturgeon are able to perform similarly across a wide range of protein:energy ratios (79 - 147 mg protein kcal-1), so long as adequate dietary energy (3,800 kcal kg-1 gross energy) is provided and essential amino acids are not limiting. Soybean meal was evaluated utilizing practical, isocaloric, isolipidic, isoenergetic test diets, designed to replace FM with increasing SBM. Juvenile Scaphirhynchus sturgeon were found to perform similarly on diets with up to 50% of FM replaced with SBM (336 g kg-1 diet). Evaluation of liver composition revealed that juvenile Shovelnose Sturgeon store less glycogen and crude lipid than other fish species, although no dietary differences were observed. Histological evaluation of the distal intestine revealed indications of SBM induced enteritis, though no statistical differences in measures were detected between treatments. This research is the first to describe optimal dietary formulation for the culture of Scaphirhynchus sturgeon.

台灣養殖漁業自1970年代起，進入快速成長時期，而在1980年代為台灣養殖漁業全盛時期，造就台灣成為「養蝦王國」、「養殖王國」揚名國際之美名，也為台灣沿海農漁村地區開拓新的漁業契機，而讓農漁民累積不少財富，故當時養殖漁業儼然成為台灣農業結構上重要之一環，對繁榮沿海農村經濟，安定農村社會，極具貢獻。 然而，諷刺的是，1980年代卻也是台灣耕地轉供養殖池之情況快速蔓延的時代，形成台灣沿海逐漸形成養殖區域性發展，卻也因為養殖漁業對於水土資源超限使用下，而超抽地下水而引起地層下陷及地下水體汙染等永世災難及耕地轉供養殖池諸多問題產生，導致環境不永續之後果，值得謀求解決之道。 本研究以質化研究中之個案研究法，以永續發展理念為基礎，運用文獻分析法及深度訪談法交互分析。先探討台灣養殖漁業管理及養殖漁業用地管理制度之演進及衍生出問題；再以宜蘭縣五結鄉季新村、錦眾村個案研究地區，深入探討台灣及宜蘭養殖漁業發展牽動五結鄉養殖區範圍擴散之可能原因及其影響，並就其耕地轉供養殖池之產業營運、違規使用、養殖環境轉變、養殖池棄養等不永續利用問題予以分析，最後提出「台灣養殖漁業與其用地管理制度改進策略」及「五結鄉養殖漁業與用地管理策略」。 經由研究發現，台灣超抽地下水及地層下陷問題最為嚴重之縣市，申請經營養殖漁業竟不需審核地下水之合法用水資格，而經個案地區研究也發現台灣及宜蘭養殖漁業發展牽動五結鄉耕地轉供養殖池之擴散，而經耕地轉供養殖池後，在養殖漁業沒落後，欲將棄養養殖池回復耕作環境困難重重，當地逐漸形成一片荒涼景象。 最後建議政府漁業單位應設計優良養殖環境之制度，即應先規劃養殖生產區並『主動』興建完成養殖專用之進水（海水、地下水）、排水之共同管線系統等相關養殖公共設施，並劃為非都市土地使用分區「養殖漁業生產區」（建議新增非都市土地使用分區），而該分區內之養殖池，有別於一般農地申請做養殖池，不應依據相同之法令規範，應放寬該養殖生產區內養殖池就地合法或是簡易申請程序以方便並快速取得合法養殖之資格，以有效管理養殖漁業減少違規使用情形發生及促進養殖漁業朝向永續發展方向邁進，並促進水土資源永續性利用。另建議政府漁業單位經全面性可行性評估後，認為不適合繼續養殖之地區應投入資源積極輔導該地區轉型，協助並引導該地區轉供較為永續利用之方向（如生態旅遊等）。 / Since 1970's the aquaculture develops rapidly in Taiwan, and becomes pre-vailing as the golden age of the aquaculture fishery in the 1980's. At that time Taiwan is well known of the kingdom of shrimp and aquaculture fishery in the world, and fishermen and farmers near the coast areas gain a new chance of incomes, so aquaculture fishery has become a very important chain of Taiwan's agriculture. It also has great contribution to flourishing village's economy and society stabilization. However, ironically, in 1980's many farms become aquaculture ponds quickly, that result in regional development of aquaculture fishery along the coast of Taiwan gradually, but overuse the resource of water and soil. Tapping groundwater inappropriately causes terrible disaster which lead to land subsi-dence and contamination of groundwater. The conversion of farms to aquacul-ture ponds cause many problems, that leads to environment being not sustaina-ble. There is an urgent need to find out relevant solutions. This research is based on two cases study the ideas of sustainable develop-ment.We adopt the modes of literature review and analysis, and depth interview. Firstly, we inquire into management system of the aquaculture industry and aq-uacultural land and the regarding problems. Secondly, we select the areas of Ji-sin village and Jin-jhong villege in Wujie Township Yilan County , in order to thoroughly inquire into possible reasons and influences that how aquaculture development in Yilan County and Wujie Township lead to the spreading of the areas for aquaculture production zone.Thirdly, we analyse problems of being not sustainable use of resources, such as the operation of the aquaculture pond, violating the rules of farmland use, changes of the cultivation environment, dis-card of aquaculture pond etc. Lastly, we put forth improvement strategies of aquaculture and its land management system both in Wujie Township and Tai-wan. Through the research, we find in counties with the most serious problems of tapping groundwater inappropriately and land subsidence in Taiwan, the gov-ernment doesn't need to examine the legality qualifications of the groundwater use when people apply for aquaculture fishery.We also find that aquaculture development in Yilan and Taiwan result in farmland conversion into aquaculture pond in the areas of Wujie Township . Because it is very difficult to make dis-carding aquaculture pond return to farmland, the region becomes a slice of desolate prospects gradually when the aquaculture decline. Finally, we suggest the Fishery Bureau of Government should design better institution for aquaculture environment. That is, they should plan for aquaculture production zone first and build public facilities of aquaculture fishery, such as the common pipeline system of using sea and groundwater for aquaculture fishery .The government should review the classification of non-urban land usage since the attributes of aquaculture ponds in "Aquaculture Production Zone" are different from others. In order to manage aquaculture fishery effec-tively, we also give some suggestions concerning decrease the occurrence of violating the rules, promoting the aquaculture fishery moving forward to sus-tainable development, and improving the sustainable use of water and soil re-source. We think to simplify application procedure of getting legal qualifications for aquaculture fishery may is not the best way but is an easy way to solve problems currently. Another suggestion is that after comprehensive feasibility evaluations, the Fishery Bureau of Government should actively invest adminis-tration resource to help areas that are not suitable for being use of aquaculture pond transferring to sustainable use, such as ecotourism etc.

No description available.