Finfish fisheries

This study reports the first evidence of the occurrence of perfluoroalkyl acids (PFAAs) in commonly consumed seafood from the coastal area of Bangladesh. Fifteen target PFAAs in 48 seafood samples (5 finfish and 2 shellfish species) were measured by HPLC-MS/MS. The results were comparable with other studies worldwide, particularly from China, Spain, Sweden, and USA. The majority of monitored PFAAs did not show clear seasonal variation. However, seafood from the southeast area (Cox's Bazar and Chittagong) showed relatively higher levels of PFAAs.

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.

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 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.

Fisheries are an important source of animal protein for most of Thailand’s population, particularly in provinces on or near the coast. Between 1978 and 1997 the per capita consumption of fish averaged 24 kg·capita-1 annually. In 1995, about 535 210 people were involved in the fisheries sector and 44% of these were engaged in small scale marine capture fisheries. Since 1982, Thailand has faced problems with the development of marine capture fisheries and their over-exploitation which has increased fishery conflicts and disputes with neighboring countries.

The Java Sea is a major fishing ground in Indonesia contributing 31% of the national marine fisheries production. Demersal and small pelagic fishery resources account for most production in the area. During the 1960s and 1970s, strong demand for fish, which in Indonesia resulted from both increased human population and increased per capita fish consumption, stimulated the development of fishing in the Java Sea. This led to development of up-stream and down-stream industries, increases in employment opportunities, and increases in the number of fishers and fishing households.

Fisheries are an important source of protein and employment for Sri Lanka’s population. The declaration of the Exclusive Economic Zone (EEZ) in 1976 gave the country a water area larger than its land area. The coastal fisheries resources consist of small and large pelagic fish, demersal and coral reef fish, invertebrates, shrimps and crabs. The small pelagic fish contribute 70% of the catch from coastal waters with an estimated annual production of 152 752 t in 1997.

This paper presents the results of analyses of the demersal fish assemblages in Bangladesh waters of the Bay of Bengal. Catch data from three trawl survey cruises from January to February 1985 covering 135 stations were utilized for community structure analysis using TWINSPAN and DCA techniques. Both techniques separated the deepwater stations (> 90 m) from the shallow areas (< 90 m).

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.

The 1995 trawl data of the research vessels Pramong 2 and 9 in the Gulf of Thailand were analyzed using TWINSPAN and DCA. Four main station clusters were identified related to geographic location and depth. Two clusters are associated with shallow water areas and the other two clusters are found in deeper areas with water depths > 30 m. Temporal analysis indicates clustering of monthly data into wet and dry seasons. Examination of species abundance data indicates that the seasonality may not be very pronounced.