During the last several years, fish production has been gradually increasing in Bangladesh. The annual growth rates of production indicate that inland aquaculture grew fastest, followed by the marine sector. On the other hand Inland capture fisheries are on a declining path. Inland aquaculture and Marine and Brackishwater sectors likely have the largest future potential for growth.
Culture fisheries included ponds, oxbow lakes, lakes, canals, borrowpits, paddy fields, seasonal water-bodies, natural depression, beels, etc. Construction of roads, embankments, development of irrigation systems separated floodplains from the continuous flowing and converted into seasonal culture fisheries through community based management practices when monsoon water drained in the dry season.
Cage-culture and pen-culture in the irrigation systems and flowing rivers contribute large to the culture fisheries. With the decreasing of natural stock beel is successfully using for fish-culture, seasonally or perennially depending on the areas and habitats.
Small water-bodies or homestead ponds are meant for family based fish rearing of quick growing species and supplementing in the diet of malnourished group. Culture fisheries are guided by a number of economically and socially viable technologies. The major technologies are carp poly-culture, rice-fish culture, cage-culture, pen-culture, rice-prawn culture, closed-beel culture, commercial carp seed culture, improved shrimp culture, shrimp-crop rotational culture, etc.
Average production from pond culture system recorded in the year 2007-’08 is about 3000 kg/ha against national average 986 kg/ha. Production from other cultivable water bodies is far below the national level. Major carps contribute highest in percent, nearly 22% of the total production. Though exotic, but well adjusted as pond fishes and contribute 13% in total production.
Rivers, tributaries, creeks, canals, baors (oxbow lakes), haors and floodplains which contain waters throughout the year are capture fisheries. Floodplains, wetlands or marshy lands areas flooded during the monsoon season and remain under water for a period of 4-6 months is also included in the capture fisheries. Capture fisheries is the major source of total production, which is estimated to represent 41% of the total inland catch. The main group is hilsa and second important group consists of the major carps. The rest are catfish, minor carps, snakeheads, shrimps and other small fishes. The inland capture fisheries are the major source of diverse livelihoods opportunities of the poor fishers.
The capture fisheries of Bangladesh are under intense pressure of natural changes and social competition. It has declined in area and productivity. This cannot be reversed, but through improved management with the goal of stabilizing the resource and by allocating it for the use of the traditional fishing communities, then the capture fisheries can continue to be a source of income for a large number of the rural poor.
Brackishwater also consider as closed culture based resources. Tidal ponds, salt pans, coastal floodplains, rice fields in the polders are included in the brackish-waters. The major product includes shrimps, white fishes, crabs, eels, etc. Shrimp are considered major commercial component of brackishwater fisheries. Shrimp sector (includes Penaeus, Metapeneaus sps. and Macrobrachium sp) is alone contributed 5.25% of the total fish production of 2.56 million mt of fish produced in 2007-2008. Bagda (Penaeus monodon) is major cultivable species. The other miscellaneous species of shrimps are chaka (P. indicus), harina (Metapenaeus monoceros) ) chama (M. brevicornes). Shrimp sector recognized internationally for its high quality shrimp produced using socially responsible and environmentally sustainable production methods.
Earlier brackishwater aquaculture was confined in some tidal floodplain areas in the southwest part of the country and exists in a very rudimentary form for decades. In the early seventies expansion of this sector started with the entrance in world export market. The increasing demand and steady rising prices of shrimp caused a silent revolution in the sector. The brackish-water aqua-farming spread over 217,877 ha till 2007-2008, distributed over several coastal districts in the country, quite common in Satkhira, Bagerhat, Khulna and Cox’sBazar.
The increased demand of shrimp in the international market resulted in a strong position of shrimp culture in the country. However, it leads to certain conflicts of rights and interest between users and land owners. Intrusion of saline water by tidal bore, aila, and other natural hazards often caused devastating loss of shrimp industries. Recent banning on shrimp export to the EU countries results loss of this expanding industries. The imposition forced to maintain quality in management, harvesting, handling, carrying, preservation, and packaging to the HACCP standard. These issues must be addressed to secure the future of this sector.
Marine fisheries are an important source and contribute 19-20% in the total harvest. A total of 490 species of finfish belonging to 133 families have been observed in marine and coastal environment, of which 65–70 species are commercially important. Hilsa, jack, anchovy, etc., are the most important pelagic species. Bhetki / Koral (Lates calcarifer), mullet (Mugil sps) are found as most important members of marine-culture. Several species of milkfish (Chanos chanos) are also occurring in the sea. A number of crustaceans (shellfish) resources including 36 species of shrimp, 3 species of lobsters including other traditional and non-traditional fisheries, such as, cuttlefish, octopus, oysters and mussels, Turtles. The sector is mainly capture based. Among marine species, major contributors are Bomabay duck (Harpondon nehereus) 1.44%, Jew fish (poa, lambu, kaladatina, etc.) 1.32% in total catch of marine source.
A dynamic change takes place over the decades in fishing effort. This has been due to the introduction of industrial fishing boats, the mechanization of traditional boats and the increased numbers of people involved in the artisanal and shore based fishery. This development has largely gone on uncontrolled with no real management of the resource. There is no clear knowledge of how the sector is coping except anecdotal evidence that the fishery is in decline. The ownership of the resource has also increasingly moved out of the hands of the fishermen into the hands of the wealthy businessmen and traders. These issues need to be addressed to ensure a sustainable utilization and management of the resource.
Paucity of knowledge, experience and initiatives on mariculture kept the sector harvest-based rather than culture-based. Culture of sea weeds, mollusks, breeding and management of green turtle are some of the recent initiatives ventilates the scope of mariculture that needs extensive research for wider expansion. Recent study and observation suggested exploring the scope of mariculture surrounding the islands of St. Martin’s, Moheshkahli, Sonadia and other coast. Research on standing crops, breeding and seed production of sea bass (Lates clacarifer), mullets (Mugil sps.) widened the prospects of mariculture. Commercialization of Artemia, marine diatom, algae, rotifer production and pearl culture in marine mussels are emphasized and recommended in the study. A number of sea weeds; Hypnea, sp.,Caulerpa racemosa. Species of commercial and medicinal value are widely distributed in inter tidal and sub tidal water of St. Martin’s Islands. Demonstration of culture technology of seaweeds indicates its economic dimension through commencing seaweed cultivation.
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