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.
The WorldFish Center is implementing the FtF Aquaculture Project in 20 southern districts in Bangladesh. The project is implemented under USAID’s Feed the Future initiative in collaboration with the Government of Bangladesh.
A mass-balance steady-state trophic model of the coastal fisheries ecosystem off the West Coasts of Sabah and Sarawak, Malaysia (10 - 60 m depth) was constructed using the Ecopath software. The ecosystem models were partitioned into 29 ecological/trophic groups. The input values (e.g. biomasses) for selected groups were obtained from the research (trawl) surveys conducted in the area in 1972. The estimated mean trophic level of the fisheries catch for both models is about 3.3.
The Ecopath approach and software were used to construct a trophic model of the coastal fisheries ecosystem of the southwest (SW) coast of India. The model consisted of 11 ecological groups and used estimated landings from all areas along the southwest coast (based on the sample surveys conducted by Coastal Marine Fisheries Research Institute for the years 1994, 1995 and 1996). The trophic model suggests high catch levels, particularly for the large and medium predators, demersal feeders and detritivores.
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.
The present study makes use of the fisheries survey data collected during the period 1984 - 87 by the multi-purpose research vessel RV Anusandhani in the waters of Bangladesh, Bay of Bengal. The data consists of twelve survey cruises directed at the shrimp resources (1985 - 87) and nineteen survey cruises directed at the demersal fish resources (1984 - 86). The biomasses for shrimp and demersal fish during the survey period were estimated, along with a detailed analysis of biomass distribution by depth zone and catch rates for important species of shrimp and demersal fish species.
Research trawl surveys have been conducted in four areas of Malaysian waters (west and east coast of Peninsular Malaysia, and waters off the coast of Sarawak and off the west coast of Sabah) since 1970. Selected surveys (1972 - 98) were used to examine the status of demersal fishery resources in each area, focusing on catch rate and biomass trends, population parameters and the exploitation rates of dominant species.
Data from trawl surveys (1961 - 95) and annual production statistics (1971 - 95) were used to examine the status of demersal fishery resources in the Gulf of Thailand. Analyses were focused on biomass trends, population parameters and exploitation rates of dominant species, and assessment of excess capacity from fishing effort and yield estimates. The results indicate by 1995, the trawlable biomass in the Gulf had declined to only about 8.2% of the biomass level in 1961.
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.