DEMAND FOR FISH IN THE PHILIPPINES: A DISAGGREGATED ANALYSIS

ABSTRACT

This paper sought to establish the fish consumption pattern of Filipino households and estimate the price and income elasticities of fish demand by species, as well as by income groups, i.e., low, middle, and high income. The study used the countrywide Family Income and Expenditure Survey (FIES) for year 2000 of the National Statistics Office, which includes over 39,000 households. A three-stage budgeting framework was used in the analysis, which estimated food and fish expenditure functions in the first and second stages, respectively. In the third stage, a system of demand equations for fish by species was estimated using a quadratic almost ideal demand system (QUAIDS) model. Parameter estimates of the model were corrected through the Heckman procedure to remove the possible bias brought about by zero consumption of certain fish species resulting from nonpreference or infrequent purchases. Results showed that estimated price and income elasticities of demand varied substantially across fish type and across income groups. All 11 fish types included in the study were found to have positive income elasticity for all income levels. Hence, fish in general can be considered normal goods, including processed fish. However, the high-priced fish types generated elasticity values greater than one, which rendered them as luxury food fish. Own-price elasticity, on the other hand, was found to be elastic in most species with values increasing as consumers climbed up the income ladder. This observation, however, was not true in the case of milkfish and tilapia (two most popular species in the country) where price responsiveness of demand was found to be higher among the lower-income groups.     

Aquaculture and poverty alleviation in Ben Tre Province,Vietnam

Research results on the effects of aquaculture on poverty alleviation have been mixed. We use Tobit, simulation models and cross sectional survey data of 285 households, in Ben Tre Province, Vietnam, to evaluate the effects of aquaculture involvement on poverty, measured using per capita consumption of less than $1.25 USD, $1.50, and $2.00 per day. The results show for per capita consumption of less than $1.25 per day that households’ aquaculture participation or productivity had no or little effect on the living standard. For income levels above $1.25 per capita per day aquaculture participation or productivity influenced the standard of living.     

THE FARMING PRACTICES AND ECONOMICS OF AQUACULTURE IN THAILAND

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.     

Comparison of intensive shrimp farming systems in Indonesia, Philippines, Taiwan and Thailand

The estimated production of cultured shrimps for 1995 in Taiwan, the Philippines, Indonesia and Thailand was 20 000, 40 000, 80 000 and 220 000 tonnes, respectively. Intensive shrimp ponds in the Philippines (71%) and Indonesia (63%), which are developed in the tidal and mangrove areas, cannot be properly treated by complete drying, owing to seepage from supply and drainage, nor by removal of the fouled layer by heavy machines such as bulldozers. Intensive farms in Thailand and Taiwan are owned by small-scale operators operating 2-3 ponds simultaneously, each ranging from 0.16 to 1.0 ha, which is the optimal size for efficient farm management and lower overhead and investment costs compared with larger farms such as those found in Indonesia and the Philippines. In Taiwan, 90% of pond water supply is mixed open sea water with underground fresh water. Pond salinity, which is kept constant at 10-15%o, causes Taiwanese farmers to encounter an array of problems which include high cost of underground water pumping, land subsidence, salinization, more pathogens and rapidly fouled bottom. Water loss by seepage in Thailand is minimal (average 23 cm in the final month), compared with Indonesia and the Philippines, because pond dikes are tightly compacted by heavy machines and high clay content (86%). Circular water movement in ponds in Thailand, facilitated by heavy aeration (13.3 hp ha^?1), aids in the settling of waste in pond centres for easy removal. Indonesia and the Philippines still maintain high water exchange systems (335 cm and 470 cm in the final month, respectively) which introduce viruses, other pathogens, excess organic loads, ammonia and other toxic particles released by nearby farms through the incoming water. Despite serious crop failures in other countries within the past few years, the annual shrimp production in Thailand still remains high because farmers have readily adopted new, environmentally friendly and locally suitable, water exchange systems such as less water exchange, and closed, full-strength seawater and freshwater systems, overcoming heavy viral and disease infections. Approximately 30% of shrimp production in Thailand comes from the freshwater areas, sometimes 200 km from the sea. Half of the Philippine farmers rely on imported feeds; this has caused high shrimp mortality owing to toxins produced from expired feeds kept in humid conditions.     

Socio-economic impacts of shrimp culture

Farmed shrimp contributed 27% of total world shrimp production in 1995 with a volume of 712 000 tonnes. Undoubtedly, the shrimp culture industry earns valuable foreign exchange for developing countries and generates jobs across the industry from fry gatherers to growers and processors. However, grave socio-economic consequences – including conversion, expropriation and privatization of mangroves and other lands; salinization of water and soil; decline in food security; marginalization of coastal communities, unemployment and urban migration; and social conflicts – have followed in the wake of, shrimp farm development in the Philippines and other tropical countries. The paper focuses on mangrove ecosystems: the valuation and cost-benefit analysis of their goods and services, and the mangrove-offshore fisheries connection. Research gaps in these areas and the need to internalize the ecological and socio-economic costs (‘externalities’) of shrimp farming are highlighted. Other recommendations include mangrove conservation and rehabilitation, enforcement of existing legislation, and introduction of environment-friendly aquaculture within the broader framework of community-based, integrated coastal area management, e.g. the traditional, extensive polyculture ponds in Indonesia.     

The impacts of integrated homestead pond‐dike systems in relation to production,consumption and seasonality in central north Bangladesh

The roles of homestead ponds and surrounding dike production of vegetables on farms in peri‐urban and rural communities in central north Bangladesh were assessed. A baseline survey sought to characterize actively managed (“active”) pond‐dike systems, producing fish and vegetables, in terms of productivity and impact compared to less intensively integrated (“passive”) and control, no‐pond households. A longitudinal survey was carried out over 12 months to explore the relationship between seasonality and livelihood outcomes in relation to location and well‐being status. Active homestead pond operators tended to have greater access to information and credit compared to passive and non‐pond households; this was likely linked to their greater literacy and greater social connectedness. They enjoyed higher incomes through fish sales and consumed more fish than passive households, which was related to their higher production, in turn explained mainly by the use of more inputs. All active, 50% passive and 38% non‐pond households were involved in vegetable cultivation; however, significantly more vegetables were produced by active households than others. The impacts of pond‐dike production were more critical for food‐vulnerable, rural households than peri‐urban households prior to monsoon rice harvest; worse‐off households suffered more prior to the “irrigated rice” harvest. Fish and vegetables raised on farm were most important during lower income months. The study supports the view that small homestead ponds can contribute to the wider food supply, and that such “quasi‐peasant” forms of aquaculture contribute to reduced poverty and enhanced dietary diversity and food security in the broader population.     

Economic contribution of fish culture to farm income in Southeast Vietnam

Rural aquaculture is the farming of aquatic organisms with extensive and semi-intensive husbandry practised by small-scale rural households for their consumption and income. From a field survey in Southeast Vietnam, using enterprise budget analysis and nonparametric tests with indices of change, adoption, and agreement, this study justifies that rural aquaculture is a good option for rural development, making an important contribution to farm income with a high adoption rate among poor farmers. Fish farmers have gained an increased level of satisfaction by means of fish culture production growth along with corresponding economic gains. This enterprise continues to play an increasing important role in their livelihoods and has potential to develop further in the area.     

湖北省黄冈专区中小型湖泊渔业增产的初步经验

一、绪说 黄冈专区共有湖泊453个,总面积185.7万亩,其中除4个“敞水湖”(面积90万亩)外,余者均可开展湖泊养殖。 本区的湖泊主要分布在长江两岸地区,多系沿江冲积平原的洼地,是自然或人工堰塞成的湖。常年水深在5米以下,一般在2～3米之间。湖底平坦,湖泥较厚。岸线曲折,港湾多。大部分湖泊与长江相通,并建有堤闸,起著调节和贮水的作用。     

鱼油微囊化工艺及其特性研究

研究了鱼油微囊工艺及特性，采用喷雾干燥法进行鱼油微囊化研究。混合表面活性剂最适HLB值为7．5。乳液粘度影响乳液稳定性及喷雾干燥效果。固形物含量与乳液粘度有关。筛选出最适壁材是阿拉伯胶、鼓甲基纤维素、蛋白粉。微囊鱼油具有良好的稳定性。微囊工艺改善了鱼油的风味。     

Conservation hotspots of biodiversity and endemism for Indo‐Pacific coral reef fishes

• 1. Distribution patterns of 3919 species of Indo‐Pacific reef fishes were analysed using GIS mapping software for the purpose of conservation prioritization of extraordinary high concentrations (‘hotspots’) of diversity and endemism.
• 2. Megadiversity countries with more than 1000 coral reef species include Indonesia, Australia, Philippines, Papua New Guinea, Malaysia, Japan, Taiwan, Solomon Islands, Palau, Vanuatu, Fiji, New Caledonia, and the Federated States of Micronesia.
• 3. The richest area for reef fishes is the renowned Coral Triangle, which includes eastern Indonesia, Sabah (Malaysia), Philippines, Papua New Guinea, and the Solomon Islands. The highest concentration of species within this region extends from south‐eastern Indonesia to the central Philippines.
• 4. Occupying only 3% of the surface area of the tropical Indo‐west and central Pacific, the heart of the Coral Triangle contains 52% of its total species.
• 5. The top‐ranked areas based on percentage of endemism are Easter Island, Baja California, Hawaiian Islands, Galapagos Islands, Red Sea, Clipperton Island, Marquesas, Isla del Coco, Mascarene Islands, and Oman.
• 6. The highest concentration of endemics per unit area occurs at remote south‐eastern Polynesian and eastern Pacific islands including Clipperton, Isla del Coco, Easter, Rapa, and the Pitcairn Group.

Copyright © 2007 John Wiley & Sons, Ltd.     

Fish culture in rainfed rice fields of northeast Thailand

Adoption of rice-fish culture by farmers in the rainfed areas of northeast Thailand is examined with reference to recent field research and extension in the region. The practice is placed in perspective with the development of aquaculture per se and the human and agricultural ecology of this heterogeneous region. Rice-fish culture is a recent activity in the region and has been promoted by government and non-government agencies with variable success among small-scale farmers. The widespread availability of private hatchery-produced fish seed and perceived decline in wild fish have been important stimuli. Rainfed rice fields are marginal agricultural environments and lack of water constrains both rice and fish production. Wild swamp fish are tolerant of these conditions and traditional systems for their management and capture have expanded greatly in recent years. In much of the region ‘trap’ ponds are used more for catching wild fish than as refuge sumps or ponds for fish culture per se; wild fish typically constitute between 20 and 80% of the total yields in stocked systems. Widespread availability of fish seed allows more farmers to try rice-fish culture but the small size of seed at purchase is still a problem particularly where carnivorous, wild fish are prevalent. Appropriate on-farm nursery techniques may improve success and adoption of hapa nursing has been high in some parts of the region. Species ratio and density of fish stocked depends mainly on their availability from fry traders; the major species stocked in rice fields are the silver barb (Puntius gonionotus), common carp (Cyprinus carpio) and Nile tilapia (Oreochromis niloticus).

Farmers adapt rice fields for fish culture as part of their whole farm strategy; benefits to rice, vegetable and fruit and livestock may be considered more important than fish yields. The high value attached to even small quantities of fresh fish is a major incentive for rice-fish culture, but women who are decision makers in terms of changes to rice fields and household consumption have often not been fully considered during promotion of rice-fish.

The relatively small areas of riceland that farmers can stock and harvest fish, low yields per unit area and high consumption of fish reduces the importance of rice-fish culture in many rural households. The analysis suggests that stocking fish in rice fields in areas with poor access to wild fish supplies from community water bodies would have most impact.

Although rice-fish culture can contribute to subsistence requirements, the high labour demand often means that intensified capture of wild fish or pond-based culture of fish are more attractive for poorer and better off farmers, respectively.     

Evaluation of the effect of stock enhancement in the coastal waters of Guangdong,China

A total of 14.573 million fish fry and 96.32 million shrimp larvae were released across 31 locations into the coastal waters off Guangdong, China, in 2010. The released fish and shrimp were sampled through a combination of market and fishing log‐book surveys. The combined fishery production reached 362 868 kg. The input–output ratio was 1:5.99 for released fish (over 3 years) and 1:11.01 for released shrimp (over 2 years). The average increase in income was 721 RMB per capita. Approximately 240 thousand fish (after 3 years) and 1.2 million shrimp (after 2 years) survived to sexual maturity and could contribute to the spawning stock. The stockings were approximately one‐seventh of the fish and one‐half of the shrimp stocking carrying capacities, respectively. Based on these results, the intensity of stocking could be increased. Stocking and recapture strategies should be adjusted to align with the optimal stocking carrying capacity determined from this study.     

THE EFFECT OF FISH QUALITY ON THE COMPOSITION AND OXIDIZATION OF FISH OIL

本文以不同质量的鱼及生产出的鱼油为原料，研究了鱼体质量对鱼油组成及氧化特性的影响。氧化程度即鱼油的化学发光强度随鱼体质量下降而上升。化学发光强度与ＥＰＡ、ＤＨＡ含量无明显关系。随鱼体质量下降，鱼油颜色由浅而深，且共轭二烯系含量、游离脂肪酸和甘油二酯含量增加。鱼油中甘油三酯与鱼体总挥发性氨基氮呈负相关。由低质鱼生产的鱼油较易氧化。     

Consumption frequencies,determinants, and habits of aquaculture species in Brazil

The Brazilian aquaculture sector faces many challenges involving internal consumption; Brazil’s per capita fish consumption is lower than its production capacity. In this study, the dataset used the Pearson correlation coefficients and ordered logit models and their odd ratios to identify relationships and estimate the probabilities of the main determinants and barriers for fish purchasing on consumption frequency levels. A sample of 1509 participants was surveyed to examine Brazil’s main consumption frequencies, determinants, and habits of aquaculture species. The study confirmed that aquaculture fishes are mainly consumed occasionally during Easter and supermarkets are the main retail channel. Tambaqui, tilapia, and white leg shrimp are the species mostly consumed amongst the sample. The results indicated that the highest probability for a consumer to increase their consumption frequency levels for tilapia is related to availability on shelves. Nutritional value is a significant determinant relating to the increased consumption frequency of grouper. Lack of desired species, not trusting the health quality of the product, and culinary options are essential determinants for consuming shrimp. Similarly, for catfish, high prices, variety in culinary options and difficulty in preparation are the main determinist affect consumption frequency levels. Also, the results indicated that income and education influence the probability of moving to a higher consumption frequency level of all species, except for tambaqui. The findings provide valuable information, especially for producers and organizations in terms of marketing and policy analysis. Marketing strategies and campaigns are recommended to promote the habit of eating fish throughout the year.

     

The Economics of Kappaphycus Seaweed Cultivation in Developing Countries: A Comparative Analysis of Farming Systems

The farming of the red seaweed Kappaphycus alvarezii and related species as raw material for the hydrocolloid carrageenan rapidly spread from the Philippines in the late 1960s to Indonesia, Tanzania, and other tropical countries around the world. Although numerous studies have documented positive socioeconomic impacts for seaweed farming, factors such as diseases and distance to export markets have led to an uneven development of the industry. Using standard budgeting techniques, this study adapted production and market data from a FAO-led global review of seaweed farming to develop comparative enterprise budgets for eight farming systems in six countries (Indonesia, the Philippines, Tanzania, India, Solomon Islands, and Mexico). Although the basic technology package is the same across countries, the study revealed large differences in the economic performance of systems due to wide variations in farm prices and the scale of operations. Although seaweed farming is a suitable activity for small-scale producers, a minimum of 2,000 m of cultures lines are still necessary to ensure adequate economic returns. Greater farming plots may be needed if farm prices are well below the average farm prices paid in Indonesia and the Philippines. Policy recommendations are made to improve the economic potential of underperforming systems.     

东、黄海冬季底层鱼类群落结构及其多样性

根据１９９１年１～２月东、黄海冬季底层鱼类资源调查资料,分析了该海域的鱼类群落结构。本次调查共捕获鱼类４５６２．４９ｋｇ,７２９３５尾,１９８种。其中,暖温种居第１位,有８７种,占４３．９％;暖水种次之,有８６种,占４３．４％;冷温种最少,有１５种,占７．６％。相对重要性指数（ＩＲＩ）大于５００的鱼类定为优势种,共有５种：竹Ｊｉａ鱼、带鱼、小黄鱼、Ｔｉ鱼、绿鳍马面Ｔｕｎ;ＩＲＩ值在５００～１００的鱼类定为常见种,共有１０种：银鲳、短尾大眼鲷、黑鳃梅童鱼、短鳍红娘鱼、黄ＡｎＫａｎｇ、细纹狮子鱼、黑ＡｎＫａｎｇ、龙头鱼、黄鲫、白姑鱼。使用种类丰富度指数（Ｄ）、Ｓｈａｎｎｏｎ－Ｗｉｅｎｅｒ多样度指数（Ｈ′）、种类均匀度指数（Ｊ′）分析该海域鱼类群落多样性特征,Ｄ值变动在１．１２１～７．０８６之间,Ｈ′值在０．５８６～     

Women's traditional fishery and alternative aquatic resource livelihood strategies in the Southern Cameroonian Rainforest

Abstract To inform the development of alternative livelihoods, the women’s traditional alok fishery in the Campo‐Ma’an National Park and buffer zone of southern Cameroon were studied over 15 months. Participatory rural appraisal was used to characterise livelihood strategies among 45 households. Thirty‐three cultured crops, nine farmed animal species and 65 non‐timber forest products, including 31 bushmeat species are cultivated in, or harvested from, the forest. Transport is a major impediment to commercial trade of all local products. In 16 alok fishing events, average weight of fish harvested was 5.14 kg per 280 m of stream distributed among an average of 23 fishers for a return of 220 g person^?1 or 40 g fish h^?1 over 5 h of work. Fish and crustacean standing stock was 25 g per linear metre or 167 t when extrapolated to the zone. Implications for rainforest livelihoods in light of the Millennium Development Goals are discussed.     

鱼油对幼鼠血清总脂、总胆固醇及组织脂肪酸组成的影响

本实验是选用雌雄两性的幼鼠,按随机区组法分成三组,分别在基础饲料中添加豆油、鱼油和鱼油浓缩物。喂养4周后,发现喂鱼油和鱼油浓缩物的两组幼鼠血清总脂和总胆固醇含量低于喂豆油组的(P<0.05)。脂肪酸分析表明:喂鱼油及喂鱼油浓缩物组幼鼠的脑、肝、脾和肾组织的二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)明显比喂豆油组的高。相反,喂豆油组的花生四烯酸和二十二碳四烯酸却比喂鱼油及喂鱼油浓缩物组的高。三组的体重增长率、血清总蛋白、碱性磷酸酶及脏体比都没有显著差异(P>0.05)。     

银离子对鱼类及其他水生动物的毒性

以白鲢(鱼种),罗非鱼(鱼种)、鲤(鱼种)、鲫(成鱼)、中华绒螯蟹(幼体)、克氏螯虾(成体)、蝌蚪等水生动物为材料,做银的毒性试验,同时分析含银水体中,鱼体内的银富集状况。试验结果表明:(1)银离子对这几种水生动物幼体的半致死浓度(LC_(50))仅在2—40ppb之间;但对成鱼的 LC_(50)要比幼体大得多。(2)在含银水体中,底层鱼类(如鲫)的银富集量最大的部位在内脏;上层鱼类(如?条)富集量最大的部位是鳃。鱼类中肌肉的富集量最小,其次是骨。