Preliminary studies on bamboo floating cage and net enclosure culture in Kainji Lake basin

The main objective of this paper is to introduce bamboo floating cage and net enclosure fish culture technology aimed at producing fish from almost all available inland bodies of water in Nigeria. The experimental approach embarked upon at Kainji Lake Research Institute is discussed. Results obtained from these experiments would help in identifying the inherent problems of this culture system and in determining the urgently needed information that will serve as management and production guidelines for adapting the technology to local conditions of varying ecological characteristics in Nigeria. Ultimately, the project is aimed at increasing the productivity of fishermen/fish farmers and hastening the development of rural communities

Small scale commercial production of tilapia fingerlings in floating bamboo net-hapas

The inadequate supply of tilapia seed is considered as one of the major present constraints to the development of the culture industry in Nigeria. The floating bamboo net-hapa hatchery/nursery system was observed to be very efficient in the mass production of tilapia (Oreochromis niloticus) fry and fingerlings at Kainji Lake Research Institute. This system was therefore, recommended for small-scale (artisanal) commercial operators consisting of fishermen families in order to increase their productivity and hasten development of rural communities. The economic analysis of this system showed that loan obtained for the recommended scale of operation can be amortized within 2 years of the project. It was emphasized that the operational and managerial skills of the fish farm operators account largely to the production cost and profitability of the enterprise

A study of the length at maturity and hooks/gill net mesh selection in Clarias lazera from Lake Chad

The minimum length at first maturity of Clarias lazera was found to be 24 cm (4.8%) for females and 20 cm (1.8%) for males. Fifty percent maturity was attained at length of 28 cm to 30 cm for both sexes; there being little difference among the sexes at this level of maturity. The modal retention lengths for gill nets were: 13 cm for 25.5 mm mesh; 18 cm for 32 mm mesh; 28 cm for 57 mm mesh; and 38 cm for 76 mm mesh. Modal lengths of Clarias lazera caught by various hooks sizes were No. 10 (28 cm); No. 11 (33 cm); Nos. 15 and 16 (28 cm). It is recommended that to protect the clarias fishery in Lake Chad, the use of gill nets of less than 57 mm mesh size and fishing hook No. 16 (and smaller sizes) which caught 43.94% of immature fishes should be discouraged

Commercial aquaculture in Nigeria: a vertically integrated approach in the commercial freshwater farming of tilapia in floating bamboo net-hapas and cages systems

Tilapia once termed "poor man's" fish, still remains as the highly-priced food fish in many developing countries. The good attributes of this fish prompt its use in intensive aquaculture vertically integrated systems (VIS) which embrace broodstock development, hatchery/nursery and growout phase. Based on the series of studies carried out at Kainji Lake Research Institute, in New Bussa, Nigeria using Oreochromis (Tilapia niloticus) in floating bamboo hapas/cages, the recommended intensive modular systems were estimated to be capable of producing 4 million Tilapia fingerlings and 729 tons fish (Market-size) annually. Cost-benefit analysis showed the venture to have high prospects. It is recommended that priority be given to Tilapia cage culture at the national level in order to contribute immensely towards increased fish production

Commercial mariculture of Oreochromis niloticus using net cages

The culture of tilapia has a long history in Africa. Fossil remains of members of the genus have been found which are about 18 million years old (Fryer and Iles, 1972). Oreochromis niloticus was the subject of detailed observations in Egypt of 5,000 years ago. A bas relief of 2,500B.C. depicts tilapia being reared in ponds in Egypt. However, despite this long history the prolific nature of this fish results in very high populations in pond culture systems. Consequently small size fish are harvested. Several methods have thus been tried to control the excessive reproduction of tilapia in captivity with only partial success. This paper reports how large size tilapia especially O. niloticus averaging at least 150g per piece can be commercially produced using floating net cages in the marine environment

The effect of long term exploitation by the gill net fishery on the multispecies fish stocks in Kainji Lake, Nigeria, 1969-1997

The findings are presented of an assessment made of the gillnet fishery in Kainji Lake, Nigeria from 1969 to the present, on the basis of data sets from commercial and experimental gillnet fishing, with the purpose to detect trends in some key fishery monitoring indicators. During this period, there has been an increase in the number of small meshed nets in the fishery resulting in a shift in the mode to lower mesh sizes; consequently, the average mesh size declined gradually in the fishery. This trend is found to be directly correlated with the decline in the CPUE and mean weight of the fish species. It is argued that the observed trend in CPUE and mean weight is forcing the fishermen to switch effort to gears such as traps which have very small meshes and can indescriminately take all sizes of the fish. It is shown that the catch composition by weight of Citharinus citharus, Lates niloticus and tilapias declined in the gillnet fishery in the late 70's and early 80's. Recent data, from 1994 to 1996, however indicates that C. citharus is recovering, but with declining mean weight. This suggests that the exploitation pattern is shifting to the smaller fish through the use of small meshed nets. In general, however, there has not been drastic changes in species bio-diversity in the Lake as a result of predatory effect and ecosystem overfishing as has happened in other great African Lakes. The species composition since lake formation continued to be dominated by fewer that 20 species. The potential yield for the lake has been estimated to be 32,166 tonnes (excluding clupeids) and the required optimum fishing effort to be 1,814 fishing canoes. In view of the relative stability of the species diversity in the lake and the current fish production level, it is proposed here that this MSY be adopted for all species. This would be achieved with the current effort level in the lake assuming that the efficiency of the fishermen and their gears do not improve. It should be reviewed after 10 or more years of catch and effort data collection. (PDF contains 65 pages)

The cast net fishery, Kainji Lake, Nigeria 1970-1997

This study was carried out to establish trends in the cast net fishery of Kainji Lake, Nigeria. The cast net fishery was second in importance to the gillnet fishery in the early years after impoundment of the lake and still continues to be an important component of the fishery. Some of the economically important species such as Citharinus spp, Tilapia spp, Labeo spp, Alestes spp and Synodontis spp are exploited by cast nets. The study has not revealed any drastic perturbation in the species diversity, catch composition, and any real ecosystem overfishing. On the other hand, both the catfish, Auchenoglanis spp and the predator Hydrocynus spp appear to have increased in the catch in recent years. Never-the-less there is a decline in the mean weight of the major exploited fish species due to the capture of under sized fishes without allowing them to grow to 'legally' marketable sizes. The use of small meshed cast net and also fishing in the shallow waters of the lake can give rise to this situation. Thus, there are signs of growth overfishing in the fish stocks. It must also be acknowledged that the situation is complicated by the fact that in a multi-gear fishery as on Kainji Lake, the cast net fishery could not be managed in isolation without due regard to the other competing gears. The catch per unit of effort (CPUE) has declined in the cast net fishery possibly due to the increase in effort by the major fishing gears over the years. The ongoing extension campaigns by the KLFPP appears to be having the desired effect, as there was reduction in the number of the major fishing gears on the Lake in 1997. It can be anticipated that if this trend continues, the CPUE will recover in the long run. Yields observed from the mesh selectivity study revealed that for major species in the cast net fishery, both by number and weight, were maximal at 2.5 inch mesh, which contrasts with the fact that current minimum allowable mesh in the Fisheries Edict for the Lake is 2.0 inch. The adoption of 2.5 inch as the minimum allowable mesh in the cast net fishery is recommended to be included in future revision of existing regulations. It is also recommended that for this control to have a desired effect, the casting of the net from the shore should be prohibited so as to reduce the incidence of juvenile mortality in the nursery areas. (PDF contains 28 pages)

A survey of fisherfolk involved in artisanal fisheries in some selected areas of Ikorodu in Lagos State

The study focused on men and women involved in artisanal fisheries in some selected areas of Ikorodu Local government in Lagos State. The random sampling technique was used to select 50 fishermen each at Ibeshe and Baiyeku sites. The results revealed that majority of the fishermen were male, christian, semi-illiterate, and married. Data were collected on capital sources, labour used, income, gear techniques and type of fish caught. Analysis showed that the highest sources of capital were from personal savings (50%). Majority of labour used were hired labour, 44% at Ibeshe and 50% at Baiyeku. Highest monthly income ranged between N10, 000 - N25, 000 at both sites. Planks were mostly used at both sites for fishing boats as well as means of transport (Ibeshe 68%, Baiyeku 72%). Common fishing gear was the gill net, The fishes caught were found to be of various tyupes. Ethalmalosa fimbriata constituted the highest fish species caught by weight and number at both sites (50%). However, the problems of capital source were most peculiar coupled with high cost of fishing materials and labour scarcity

Evaluating the role of energy efficiency labels in the prices of household appliances: the case of refrigerators

4 p.

Linking Reduced Deforestation and a Global Carbon Market: Impacts on Costs, Financial Flows, and Technological Innovation

25 p.

The Determinants of Energy Efficiency Investments in the U.S.

31 p.

Price Premium for High-Efficiency Refrigerators and Calculation of Price-Elasticities for Close-Substitutes: Combining Hedonic Pricing and Demand Systems

21 p.

Incubadoras y aceleradores de crecimiento: modelo de apoyo a las start-up tecnológicas

[ES]Las políticas de apoyo al emprendimiento se han demostrado imprescindibles para el desarrollo económico de los países. En este contexto las conocidas incubadoras de empresas juegan un papel importante, pero los innovadores aceleradores de crecimiento que están logrando convertir pequeñas start-up en grandes compañías de base tecnológica se presentan como una apuesta para el futuro. La unión de ambos conceptos constituye un modelo eficaz de apoyo a las start-up tecnológicas. En el trabajo se presentan varios estudios que demuestran que mientras que, en las incubadoras los recursos más valorados son el ahorro de costes y el mentoring, los aceleradores obtienen muy buena calificación en todos sus ámbitos. Aun así la facilidad para obtener financiación y el mentoring también son los aspectos más valorados por los participantes en la aceleración. Además se han utilizado dos casos de éxito con el objeto de proponer un corolario de buenas prácticas que ayude entre otros, a la mejora de la situación de la Comunidad Autónoma del País Vasco (CAPV) en cuanto a emprendimiento se refiere.

Recasting the Net: Defining a Gender Agenda for Sustaining Life and Livelihoods in Fishing Communities

Thirty-nine participants from 18 countries, including women fishworkers, representatives of fishworker organizations and NGOs, activists and researchers, met at Mahabalipuram, India, during 7-10 July 2010, to discuss the theme “Recasting the Net: Defining a Gender Agenda for Sustaining Life and Livelihoods in Fishing Communities”. The workshop was meant to reflect on what needs to be done to develop a ‘gender agenda’ for sustaining life and livelihoods in fisheries. It was also organized against the backdrop of the growing international recognition of small-scale fisheries and efforts to enhance their contribution to food security and poverty alleviation, as evidenced in the deliberations of the the Committee on Fisheries (COFI) of the Food and Agriculture Organization of the United Nations (FAO). This publication—the proceedings of the Mahabalipuram workshop—will be useful for fishworker organizations, gender activists, researchers, policymakers, fish farmers, members of civil society and anyone interested in gender, fisheries and livelihoods. (PDF contains 89 pages)

Certificación energética de la vivienda de Iker Elizundia Lopez y proyecto de posibles mejoras

[ES]Teniendo en cuenta la actual normativa europea y española, que tiene como objetivo principal el cumplimiento de la reducción de emisiones que se recoge en el protocolo de Kyoto y en el plan 20/20/20, en el siguiente trabajo se ha realizado la certificación energética de la vivienda de Iker Elizundia Lopez, que ha resultado en una calificación de F. Además, se ha propuesto una serie de mejoras con objeto de conseguir una calificación de D, mínimo legal para edificios de nueva construcción. Dichas mejoras, suponen una reducción del 63% de las emisiones, así como un considerable ahorro económico.