Thesis (Ph.D.)--Memorial University of Newfoundland, 1999. / Accompanying floppy disk consists of Appendix H: Presentation of models in the STELLA II environment. Bibliography: leaves 217-249.

Thesis (Ph.D.) - University of Queensland, 2001. / Includes bibliography.

M.Sc. (Zoology) / Please refer to full text to view abstract

Ph.D. (Zoology) / Please refer to full text to view abstract

by Siu-ming Chan. / Bibliography: leaves 247-259 / Thesis (M.Ph.)-- Chinese University of Hong Kong, 1984

by Wo-wing Cheng. / Thesis (M. Phil.)--Chinese University of Hong Kong, 1981. / Bibliography: l. 265-272.

This thesis is concerned with social and economic aspects of freshwater prawn (Macrobrachium rosenbergii) culture development in converted paddy field gher systems in SW Bangladesh, based on economic features of prawn production and social impacts within and around prawn farming communities. Based on a sample of 400 farmers from the four different zones in Bagerhat district in SW Bangladesh, 345 (86.25%) cultured prawn with fish and rice in their gher. The culture period is typically nine months, wild fry are stocked when available in May-June and harvested from November to January. A variety of feeds are used but the preferred material is the freshwater snail, Pila globosa. Productivity is variable, averaging 432 kg ha-!. The freshwater prawn is a highly valued product for international markets and is therefore almost all exported. All farmers in all zones and different gher size categories made a profit, with seed and feed dominating variable costs. Considerable variation in production costs and profitability was observed. The culture of prawn in gher systems is technically possible in a variety of conditions though expanding small scale of farming mainly depends on reducing production costs. Future targets could be to integrate with other agricultural activities especially dike cropping and rice production in the monsoon. The livelihoods of a large number of people are associated with prawn farming. Four different fry, snail and prawn markets were surveyed, including a sample of 60 fry catchers, 40 fry traders, 75 snail collectors, 40 snail traders and 40 prawn traders. A sample of 200 women, associated with gher farms was also surveyed. In spite of socio-economic constraints, most of the households of farmers (81 %) have improved their status through prawn farming where prawn have brought out clearly positive changes of economic activities and generated new employment. All appeared to have gained from their activities, women have enhanced their position in families and societies. However, concerns arise about the long-term sustainability of prawn farming due to high production costs, low supply of wild fry and snail meat, poor natural resources, poor institutional support and inadequate extension services, all of which have affected sustainable livelihoods of farmers and associated groups. It may necessary to establish local ingredients feed industries, prawn hatcheries and to provide low-interest credit with institutional and policy support for sustainable gher farming.

Thesis (Ph. D.)--University of Hong Kong, 1992.

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

Thesis (M.Sc.), Memorial University of Newfoundland, 2000. / Bibliography: leaves 98-111.