Farming Requirements and Site Selection Criteria

1. Salinity
   Asian sea bass is a euryhaline species, meaning it can thrive in varying salinity levels from freshwater to seawater. However, farming is most effective in brackish waters with salinity levels ranging between 10-30 ppt. Coastal and estuarine regions are ideal for farming due to the stable salinity conditions.
2. Temperature
   Optimal growth is achieved in warm waters of 26-32°C. Temperatures below 20°C for prolonged periods can cause mortalities, making warm climates essential for successful farming.
3. Water Quality
   The preferred water parameters for Asian sea bass farming include:
   • pH: 7.5-8.5
   • Dissolved Oxygen (DO): 4-9 ppm, with floating net cages offering 7-8 ppm due to constant water flow.
     Sites with low microbial loads are necessary to ensure healthy fish growth and minimise disease risks.
4. Water Exchange
   Locations with strong currents (1-2 knots or 50-100 cm/sec) and tidal fluctuations (2-3 m) help maintain clean water in cages. Floating net cages placed at least 2 m above the seabed prevent siltation and waste accumulation.
5. Protection from Strong Winds
   Farms should be established in protected bays, lagoons, or coves to shield cages from strong winds and large shipping activities.
6. Biofouling and Predation
   Sites should be assessed for biofouling organisms and predator risks, as these factors significantly affect maintenance efforts and fish survival.

Advantages of Cage Farming for Asian Sea Bass

1. Rapid Growth and High Yield
   Asian sea bass grows quickly under optimal conditions, contributing to large-scale production and meeting high consumer demand.
2. Economic Viability
   Cage farming requires lower land investment compared to traditional pond farming, making it cost-effective. The species’ high market value ensures a strong return on investment.
3. Efficient Water Flow and Oxygen Levels
   Floating net cages facilitate continuous water exchange, providing ample dissolved oxygen and removing waste, which supports fish health and growth.
4. Adaptability to Diverse Environments
   The species thrives in freshwater, brackish water, and seawater, making it suitable for diverse farming locations.

Challenges of Cage Farming for Asian Sea Bass

1. Cannibalism and Feeding Challenges
   Asian sea bass is highly cannibalistic, particularly during its juvenile stages, requiring careful size grading and monitoring to prevent stock losses.
2. Biofouling and Predator Risks
   Biofouling organisms increase net maintenance efforts, while predators like larger fish and birds pose threats to stock.
3. Temperature Sensitivity
   Farming is unsuitable in regions with fluctuating or cooler temperatures, limiting its geographical scope.
4. Site Maintenance and Monitoring
   Cage farming demands regular cleaning of nets and close monitoring of water quality, adding to operational costs.
5. Environmental Impact
   Without proper waste management, uneaten feed and fish waste can accumulate beneath cages, affecting local ecosystems.

Asian sea bass cage farming presents a lucrative opportunity for aquaculture due to its fast growth, high market demand, and adaptability. However, challenges such as biofouling, cannibalism, and environmental management require careful attention. With proper planning, adherence to best practices, and environmental sustainability measures, cage farming for Asian sea bass can significantly contribute to meeting the rising demand for seafood while supporting economic growth in the aquaculture industry.

The post Asian Sea Bass or Barramundi farming in cages appeared first on Seafood Network BD.

Within Bangladesh’s current maritime boundaries, the productive economic sectors of the blue economy are highlighted and taken into consideration in order to harness and fully utilize ocean-based resources. These ocean-based resources can offer a solid foundation for revenues and economic advantages if they are handled with effective planning and cross-sectoral coordination of public-private partnerships and investment.

To grow marine aquatic species/groups like finfish, shellfish, and seaweed for commercial farming and human consumption, marine aquaculture is defined as the installation of land-based ponds, enclosures/cages in the onshore and offshore environments. Over the past 40 years, Bangladesh has made few attempts to advance mariculture, with the exception of tiger shrimp (Penaeus monodon) farming, which uses time-honored and modernized comprehensive traditions in the coastal areas.

Major Constraints:

When it comes to salinity, temperature, pH, dissolved oxygen, nitrate, and ammonia, marine creatures are extremely sensitive. They are also susceptible to disease and predators. Cyclones, pollution, and the effects of climate change are only a few examples of manmade and natural activities that might cause uncertainty in mariculture operations. Many species need a long time to reach a size that is suitable for marketing and require a sizable initial investment and working capital. The main obstacles and challenges to the development of mariculture in Bangladesh are (i) the suitability of the site, (ii) the accessibility of seed and broodstock, (iii) the price and accessibility of feed, (iv) the availability of skilled manpower, (v) market access, (vi) financial resources, (vii) logistics support, (viii) environmental concerns, and (ix) biosecurity.

Any species that may be farmed requires seed, and in cases when natural seed is not available, hatcheries are necessary. Unfortunately, the country lacks marine finfish or crab hatcheries, which are more essential for the growth of mariculture. For some species (such as tiger shrimp and carnivorous finfish), intensive feeding with high-quality food (both live and supplemented) is necessary to maximize output, shorten grow-out times, pay off investment in ponds or cages more quickly, and improve profitability. This might not be desirable for reasons of food security because it could raise production costs, financial hazards, and the risk of disease. All of these crucial aspects need to be taken into account when creating production models.

Preventive Measures:

Under the eighth five-year plan of the government of Bangladesh and the concept of blue economy development, mariculture technology should be successfully implemented in coastal, near-coastal, and offshore locations. The nation will be able to meet its population’s needs for bulk protein in their diets and reap long-term advantages in the economic spheres. Through training programs and demonstrations, Bangladeshi farmers and researchers could access the trained labor in mariculture found in China, Vietnam and Indonesia. To produce adequate and chosen marine fin fish, shellfish, and plants for the long-term advantages of Bangladesh’s economy, environment, and coastal communities, a viable and sustainable mariculture business need to be developed. Following that, ministries, departments, and research institutions, as well as interested private entrepreneurs, should work together to develop a strategy for the effective development and implementation of marine aquaculture farming in the country’s coast, inshore, and offshore areas.

Farhana Islam
Agriculturist, Researcher
Fisheries Resource Management, CVASU

The post Concerns and remedy of mariculture development in Bangladesh appeared first on Seafood Network BD.

Criteria for being potential species:

The potential candidate species for mariculture were chosen after taking into account a number of specific factors.

1. Local environmental conditions
2. Local market drivers
3. Available knowledge and capacity
4. The Ecosystem Approach to Aquaculture (EAA).

The species chosen, in particular, were native to the environment in which they were to be cultured, with brood stock sourced from local populations and produced in local hatcheries. We also took into account the species’ life history characteristics, such as trophic level, feeding biology, growth rates, and suitability for cultivation in net cages.

Potential fish and shellfish for mariculture

Production of fish and shellfish species can contribute significantly to livelihoods in some coastal areas, though suitable sites are likely to be scarce and husbandry more demanding. However, this may represent a good opportunity for private companies and other non-governmental organizations to produce high-quality export products. Export-oriented production of these species holds great promise for assisting Bangladesh in developing a blue economy.

The potential candidate species for mariculture are including below,

1. Hilsa shad (Tenualosa ilisha)
2. Seabass (Lates calcarifer)
3. Grey mullet (Mugil cephalus)
4. Black tiger shrimp (Penaeus monodon)
5. Mud crab (Scylla serrata)
6. Green mussel (Perna viridis)
7. Clam (Meretrix meretrix)
8. Oyster (Crassostrea madrasensis) and
9. Sea cucumber (Parastichopus californicus)

Marine algae:
Because of their high biomass productivity and ability to remove airborne and waterborne pollutants, algae represent a sustainable energy source. Bangladesh has 244 seaweed species, including 19 commercially important species, and approximately 5000 metric tonnes of seaweed biomass is available.

Macroalgae:
Seaweed is used in phycocolloid or hydrocolloid, cosmetic, biofuel, biotechnology, pharmaceutical, waste water treatment, and bioplastic industries in addition to human consumption. St. Martin’s Island’s water quality parameters and rocky substratum make it an ideal location for naturally occurring seaweeds.

1. Gracilaria sp.
2. Hypnea sp.
3. Enteromorpha sp. and
4. Kappaphycus sp.

Microalgae:
Microalgae (single-celled algae or phytoplankton) play an important nutritional role as feed for marine animals in the open sea and aquaculture. In Bangladesh, microalgae oil is used to make biofuels.

1. Skeletonema costatum
2. Thalassiosira sp.,
3. Chaetoceros gracilis,
4. Tetraselmis sp. and
5. Nanochloropsis oculata

Bangladesh currently contributes very little to total production. Culture of these species, on the other hand, is a low-investment activity with high returns.

There is growing interest in the production of these marine and coastal species due to the importance of social, cultural, food, nutrition, and conservation perspectives. Domestication of these for artificial propagation and mariculture in cages, intensive and semi-intensive, represents a potential option for contributing to the country’s blue economy development.

Farhana Islam
Agriculturist, Researcher
Fisheries Resource Management, CVASU

The post Potential species for mariculture in Bangladesh’s coastal water bodies appeared first on Seafood Network BD.

Twenty six potential Blue Economy sectors have been identified by the MoFA which include the fishery, maritime trade and shipping, energy, tourism, coastal protection, maritime safety and surveillance for development of blue economy in Bangladesh. It also covers a wide range of activities, including renewable energy, fisheries, maritime transportation, waste management, tourism, and climate change.

The coastal and marine environment is becoming increasingly important in achieving the country’s social, economic, and strategic goals. The oceans economy, also known as the blue economy, is a concept that promotes economic growth, environmental sustainability, social inclusion, and the strengthening of ocean ecosystems all at the same time. It is now critical to demonstrate measurable progress toward critical internationally agreed-upon targets for a variety of issues such as fisheries, aquaculture, habitat protection, and pollution reduction, among others.

Mariculture will incorporate the value of natural capital into its development, respecting ecological parameters throughout the production cycle, creating sustainable, decent employment, and offering high-value commodities for export under the Blue Economy.

Mariculture encompasses a wide range of activities that are carried out in habitats ranging from coastal lagoons to the open ocean using a variety of techniques ranging from extensive to intensive. A wide range of food chain species, from single cell algae to pelagic predators like seabass (Lates calcarifer) and groupers, are now farmed commercially.

The main theme of mariculture and the focus of blue economy development plans in Bangladesh is integrated multitrophic aquaculture (IMTA), which is where diversification of aquaculture results in greater benefit (e.g. economic) over single species farming due to lower environmental impacts and better social acceptance. IMTA boosts output by farming species from different trophic levels, such as fish, mollusks, and crustaceans, in the same production system while minimizing the use of supplementary inputs, such as artificial feed. All cultivation components have an economic value with these processes (IMTA), as well as a key role in environmental and societal services and benefits. While having little impact on the environment, this cultivation technique has become more complex and intensive, necessitating infrastructure development and increased human capacity.

Farhana Islam
Agriculturist, Researcher
Fisheries Resource Management, CVASU

The post Mariculture deserves an attention to enhance the blue economy of Bangladesh appeared first on Seafood Network BD.

A total of 26 profitable blue economy development and economic sectors have been identified in Bangladesh within its current 1, 18, 813 sq. km maritime boundaries for the full exploitation of ocean-based resources. The marine fisheries and aquaculture sector has the greatest potential for boosting overall economic growth and improving the standard of living for Bangladesh’s many thousands of coastal rural residents. Aquaculture and marine fisheries hold great promise under the blue economy model.

Over the past 40 years, Bangladesh has made few attempts to advance mariculture, with the exception of Black tiger shrimp (Penaeus monodon) farming, which uses time-honored and modernized comprehensive traditions in the coastal areas. There are vast opportunities for thriving mariculture along the coast, in the vicinity of the beach, and offshore after the ultimate resolution of maritime border conflicts. With coastal and marine species including seaweed, macro algae, shellfish (such as mussels, oysters, etc.), sea urchin, sea cucumber, etc., Bangladesh may quickly begin marine aquaculture.

The mariculture of marine species such as sea bass (Lates calcarifer), grey mullet (Mugil cephalus), pomfret (Pampus argenteus), hilsa (Tenualosa ilisha), saline-tolerant tilapia, and others. The mariculture of marine shellfish such as shrimp (Penaeus monodon, P. indicus, P. Merguiensis), mud Seaweeds (both macro and micro algae), mussels including the green mussel (Perna viridis), the clam (Meretrix meretrix), and the oyster (Crassostrea madrasensis), corals, sea cucumbers, sea urchins, and other marine non-traditional species are also crucial for marine aquaculture in Bangladesh.

The country would be able to achieve the desired solutions for the requirements of mass protein in the diet of the people for the success of mariculture. It will be helpful to obtain sustainable benefits in economic sectors. Mariculture are implemented under the concept of blue economy development and the seventh 5 Year Plan of the Government of Bangladesh. If these opportunities are successful, GDP of Bangladesh will enhance to great extant.

Because of the growth of mariculture, it lowers the market value of wild fish, shrimp, mollusks and consequently, the investment in fishing fleets. It can ease pressure on these species, increase stock by reducing overfishing and less bio-fuel consumption. It helps to maintain a balance in coastal and marine ecosystems.

Properly managed coastal aquaculture and mariculture offer considerable potential for green growth and job possibilities for coastal communities while releasing less CO2. Many coastal communities rely on mariculture as a major source of income and employment, as well as a major producer of aquatic food in coastal and deeper oceans. Through prospects for export, mariculture can assist both food security and economic growth. The economy and environment of Bangladesh can be enhanced by creating a strong and long-lasting mariculture sector there.

Mariculture has enormous potential for the growth of Bangladesh’s blue economy. The government should ascertain the present condition of the prospects and difficulties for expanding the sector. The socioeconomic situation of the country can be improved by developing its mariculture system through the wise use of marine resources.

Farhana Islam
Agriculturist, Researcher
Fisheries Resource Management, CVASU

The post Mariculture, a potential industry to add earnings in Bangladesh’s economy appeared first on Seafood Network BD.