The study objectives are: (i) to describe the settlement and household conditions and activities in the coastal area of Pakistan; (ii) to analyse the current behaviour of shrimp fishermen, and to describe the shrimp marketing system, and government policy towards the shrimp fisheries sector; (iii) to compare the current technology and economics of Pakistani shrimp farming with those of other shrimp-producing countries; (iv) to identify the scope for the future development of shrimp farming in Pakistan and the implications for fishermen households; and (v) to assess the future overall economic viability of the Pakistan shrimp farming sector. The research comprises: (a) a survey of current shrimp fishing in Pakistan; (b) reviews of shrimp farming in major producing countries; (c) budget analyses and linear program modelling of shrimp and other household enterprises, and (d) cost-benefit, financial, sensitivity, and policy analysis of shrimp farming in Pakistan. The conclusions/results include: (i)  Shrimp fishermen households in Pakistan have experienced a downward trend in their living standards over the last two decades due to over-exploitation of wild shrimp. (ii)  Good prospects for Pakistan farmed shrimp exist on the world market. (iii)  Suitable land is available, and a government-sponsored shrimp hatchery has started work to provide postlarvae. (iv)  Shrimp fishing households could reallocate their labour and other resources towards shrimp farming and thus be able to reap substantial amount of net benefits. (v)  Shrimp farming is economically viable along the Pakistani coastline. (vi)  Awareness of opportunities for shrimp farming on a modern technical, environmentally friendly and sustainable basis should be disseminated in the coastal areas of Pakistan. (vii)  Government assistance in the farm land allocation and institutional credit will be necessary help to boost the shrimp farming industry in the coastal areas.

No description available.

No description available.

Thesis (Ph.D.)-- University of Adelaide, Dept. of Environmental Biology, 1999. / Copies of author's previously published articles inserted. Bibliography : leaves 201-217.

Thesis (Ph.D.) -- James Cook University, 2006. / Typescript (photocopy) Bibliography: leaves 104-112.

Thesis (Ph.D.)--Curtin University of Technology. / Cover title. Bibliographical references: p. 218-224.

Thesis (Ph.D.) - University of Queensland, 2004. / Includes bibliography.

On the Red Sea coast of Saudi Arabia ponds utilising seawater drawn from wells have an average salinity of 43%o and temperatures ranging from 23-33°C. The present study has demonstrated that yields of up to 4.3 tonnes ha"' of the Indian white shrimp Penaeus indicus at 20 g size may be obtained in these ponds. P. indicus was isolated from local stocks (Gizan) and has now been cultured through several generations at the Fish Farming Centre. Present work has determined that the optimal salinity for larval culture is 30960 and for nursery culture 25-30960. The best stage for transfer from nursery to growout pond (43960) is about PL25. Comparison with biological data for P. indicus cultured elsewhere indicates that Red Sea populations may be preadapted to tolerate high salinities. The potential for artificial feeds to replace live feeds in P. indicus larval culture from Z1 to PL1 and PL5 using microencapsulated feeds, Nippai and Frippak has been investigated. Results reveal that 50% replacement with Nippai and Frippak is possible giving comparable growth to the control, but poorer survival. Also comparative growth trials were conducted with post larval P. indicus (PL5-PL30) spawned from Red Sea stock and cultured through larval stages on five feeds (Chaetoceros, Tetraselmis and Artemia). Post larvae were reared on commercial feeds: Taiwanese, Nippai, Frippak and 4 formulated feeds based on locally available ingredients at 28-30°C and at 3016 and 42i salinities. Feeding trials at 42% produced poor survival, but at 30% all treatments gave over 50% survival to PL25, at which stage shrimp are ready for stocking in growout ponds. Although the Taiwanese feed produced the overall fastest growth, it was not significantly better (P > 0.05) than two locally formulated diets (FFC1,4) or Frippak. Survival rates of over 60% where achieved on all diets with the exception of Nippai and Taiwanese feeds. Yields were significantly higher (P < 0.05) on one of the locally prepared diets (FFC1) than Taiwanese and Nippai, and Taiwanese than Nippai. All diets yielded significantly more shrimp biomass at 30960 than 4216 (P > 0.05). The relative costs of imported and locally produced diets are discussed and it is concluded that it is possible to produce cost-effective nursery diets in Saudi Arabia. A growout feeding study for P. indicus juvenile utilising 4 locally formulated diets compared with a Taiwanese diet revealed no significant difference (P. > 0.05) in survival nor in growth or yield amongst all diets. However growth was slow due to low pH and high ammonia levels. Finally shrimp density production trials at 20, 40,60 and 80m"2 during winter and summer were conducted in cages placed in a rubber lined pond. For all densities; yields were significantly higher in summer than winter with an overall average of 3.41±1.5 tonnes and 4.04±2.36 tonnes 180 days-- for winter and summer respectively. Yield at 80m'1 was highest but was not different from yield at 60m'2. Based on average harvested size and market price the density of 60. =was regarded suitable for growout culture.

The effects of water movement or agitation on the biological performance of planktonic organisms under intensive culture have been rarely studied quantitatively. Stagnation or minimum values are considered important in the problem of scale-up based on optimum conditions. Near stagnation, inadequate water movement brings about undesirable effects, e.g. accumulation of metabolites, uneven distribution of feed and low dissolved oxygen concentration. An important mechanism associated with water movement at these conditions is the oxygenation process which defines the oxygen transfer rate from the gas to the water. Experiments were conducted using potable water to determine the overall oxygen mass transfer coefficient in two types of container geometries; a) cylindri-conical tank and b) oblong-shaped center- partitioned raceway. For each type of container, three geometrically similar sizes were investigated with scale ratio of approximately 1:2:3.5. Agitation was induced by the introduction of air into the system. General correlations for both tank geometries were obtained from experimental data and were expressed in terms of the operating and geometric parameters. The correlations are in the form of dimensionless groups (Froude and Reynolds numbers) making them appropriate for scale-up estimates. The general correlations for the overall oxygen mass transfer coefficient were subsequently used to provide the scaling equations to define the operating parameters in different sizes of containers for the culture of brine shrimp in sea water fed with rice bran. The high correlation coefficient obtained for the relationship between total brine shrimp biomass production and the overall mass transfer coefficient applicable to different sizes of both the cylindri-conical tank and the raceway indicates that the overall oxygen mass transfer coefficient is an effective scale-up criterion in brine shrimp culture. / Graduate and Postdoctoral Studies / Graduate

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