Benefits derived from selective breeding have been demonstrated in livestock and in some fish species, but by contrast, there have been few systematic selection programs reported for shrimps. Improving growth rate has been identified as the most important trait in the breeding objective for cultured shrimp species. In the present study we analyzed a four generation data set from a fully pedigreed selective breeding program for giant freshwater prawn (GFP in Vietnam. We estimated phenotypic and genetic parameters for body and carcass weight traits.
India is endowed with a continental shelf of 0.5 million km2 and an exclusive economic zone (EEZ) of about 2 million km2. Almost half (39%) of the Indian population utilizes the marine fisheries resources. India ranked sixth worldwide in total fish production (4.95 million t) and second in inland fish production (2.24 million t) during 1995 - 96. Fish production expanded from 0.75 million t in 1950 - 51 to 4.95 million t in 1995 - 96, giving a significant increase at a cumulative growth rate of 4.2% per annum.
Spatial and temporal variations of the demersal fisheries resources of Malaysia were studied using multivariate analysis of their abundance (biomass) from research trawl surveys in relation to geographical and environmental parameters. TWINSPAN results indicate that the demersal resources of Malaysia can be geographically divided into five major species assemblages. Two assemblages are in Peninsular Malaysia and three assemblages are in Sabah and Sarawak waters.
Settlement ponds are used to remove particulate and dissolved nutrients in Australian land-based aquaculture wastewater. At best, marine and brackish water settlement ponds reduce total suspended solids by 60%, but their efficiency is inconsistent. Functional improvements to nutrient removal systems are essential to provide uniform and predictable treatment of flow-through aquaculture wastewater. Furthermore, environmental regulation of discharge from intensive systems in Australia is increasing, providing the impetus to upgrade rudimentary single-step settlement pond systems.
A preliminary mass-balance trophic model was constructed for the coastal fisheries ecosystem of the West Coast of Peninsular Malaysia (0 - 120 m depth). The ecosystem was partitioned into 15 trophic groups, and biomasses for selected groups were obtained from research (trawl) surveys conducted in the area in 1987 and 1991. Trophic interactions of the groups are presented. The network analysis indicates that fishing fleets for demersal fishes and prawns have a major direct or indirect impact on most high-trophic level groups in the ecosystem.
The biomass of 40 ecological groups, the diet composition of prey and predators, production/biomass (P/B) and consumption/biomass (Q/B) ratios, and catches were used as basic input to parameterize an Ecopath model of the Gulf of Thailand. Following construction of a mass-balance ecosystem model, a time-dynamic simulation model (Ecosim) was used to simulate the impact of change in fishing effort. This was done using time series data to validate the historic fisheries development in the Gulf of Thailand prior to using the model for forward-looking simulations.
The present study examined the variation in survival, proportion of male morphotypes, female and male proportion, female reproductive status and tag losses in nine crosses from a complete (3 × 3) diallel mating of three populations of Macrobrachium rosenbergii in India. The populations originated from Gujarat (north-west), Kerala (south-west) and Odisha (east), representing different agro-ecological regions in India. Progeny from 60 families (4773 juveniles) were individually tagged and reared for 16–17 weeks in earthen ponds. Binary logistic regression was used to analyse the data.
Relative biomass per recruit of adult (i.e. sexually mature) fin to shellfish is shown to help in identifying levels of fishing mortality likely to lead to recruitment overfishing. This is illustrated with data from a Malaysian penaeid shrimp fishery.
The fishing industry in the Philippines was tantamount to a marine capture fishery in the 1950s to 1960s. Aquaculture and inland fishery production were not significant. Only during the 1970s did aquaculture and inland capture fisheries contribute significantly to fish production. From 250 000 t fish production in 1951, this increased substantially to 1.6 million t in the 1990s. An average 4.3% was contributed by fisheries to the gross domestic product from 1988 - 98. Fisheries export earnings reached P12 billion in the 1990s.
Bangladesh has an exclusive economic zone (EEZ) of 164 000 km2 and a continental shelf area of 66 440 km2. Artisanal (small scale) fisheries extend from the coast to 40 m while industrial (commercial scale) fisheries operate beyond 40 m depth. The coastal fisheries of Bangladesh exploit a complex multi-species resource. There are 18 demersal and pelagic species, seven species of larger pelagic and 10 shrimp species that are commercially important among the fishes exploited.