What is Aquaculture?

Fish and fish products are considered important in eradicating hunger and malnutrition in many parts of the world. Global demand for fish protein products has increased with population growth and rising living standards. According to the Food and Agriculture Organization (FAO) of the United Nations, total fish consumption has increased by 122% from 1990 to 2018. Capture fisheries alone cannot meet this increasing demand due to harvest stagnation and overexploitation of resources. This, along with the advancement of technology, encouraged people to domesticate aquaculture and breed fish in all kinds of aquatic environments.

Aquaculture is the method of breeding, cultivating and harvesting marine and freshwater fish and other aquatic organisms in a controlled environment. As per the latest FAO report, a significant share of consumed protein (52 percent) comes from aquaculture based fisheries. Aquaculture has expanded the availability of fish to regions and countries with limited or no access. It is key to ensuring food security in the future, where fish are accessible to everyone at affordable prices. Aquaculture originated in China about 4000 years ago, and today, China (35 percent) and other Asian fish producers (34 percent) dominate the global aquaculture market.

Aquaculture in Sri Lanka

Sri Lanka is an island nation with an Exclusive Economic Zone (EEZ) of 200 nautical miles in the Indian Ocean for fishing. The country mainly depends on natural fish production, where more than 90% of seafood is still caught wild. These unsustainable practices are a major threat to the entire aquatic ecosystem. Aquaculture was introduced to Sri Lanka in the early 1980s to solve these issues, with investment from large and medium scale multinational corporations. It has minimal impact on the environment and provides income generation opportunities that are non-competitive but complementary to the traditional fishing industry.

Aquaculture has been identified as a new industry that can contribute to the national economy and create new employment opportunities. According to the research study on New opportunities for Aquaculture in Sri Lanka, there is a strong demand for the seafood varieties produced in Sri Lanka in local and global markets.

Fish farming is mainly carried out in the Eastern, Northern, Uva, North-western and North-central provinces of Sri Lanka, due to the availability of suitable space and environmental conditions for aquaculture. The industry is highly concentrated on shrimp and prawn farming in the mangroves, salt marshes, and brackish water areas. According to the Sri Lanka Export Development Board, there are more than 3600 prawns and shrimp farms in Sri Lanka.

Fish farmers are also considering other alternatives that are easier to raise and less vulnerable to disease. Due to this, offshore fish farming in Sri Lanka is now being extended to other species of fish and aquatic organisms such as cage-raised sea bass, tilapia, carp, finfish, seaweed, oysters, mussels, lobsters, sea cucumbers and mud crabs. These products are selling profitably in local markets, and they have the potential to be exported to overseas markets, especially to Europe and Asia.

National Aquaculture Development Authority (NAQDA) and the National Aquatic Resources Research and Development Agency (NARA) have initiated several R&D projects to accelerate this movement. They also have established few cultivation zones to harvest shrimp and other seafood species like crabs, sea cucumbers, oysters and mussels. As stated by the National Aquaculture Development Authority, in 2019, Sri Lanka has produced over 17,000 metric tons of fish based on aquaculture.

Feed Management

Feed management is vitally important for efficient aquaculture. Both overfeeding and underfeeding have negative consequences which may affect the viability of the farm. Underfeeding lowers the growth and survival rates of fish, which can lead to loss of production. Overfeeding is a waste of expensive fish food. It can also cause water quality problems that require costly corrective measures. Also, feeding rates are not constant throughout the growth cycle of fish. It may vary according to the type, size and age of the fish and the water conditions.

Water Quality

Temperature, pH, dissolved oxygen concentration, and salinity are some aspects that determine water quality. Low water quality leads to poor growth, disease or parasite infestations and reduced mortality of farmed fish. Different species have their optimum range of water quality, where they can survive, grow and reproduce. Farmers need to ensure that water quality conditions are maintained within the optimum range all the time. Hence, it is necessary to measure temperature, pH and DO level with sufficient accuracy for the management of aquaculture farms.

Challenges faced by local fish farmers

Aquaculture farmers in Sri Lanka can sell their produce to high-end markets around the world. But, it is necessary to adhere to strict standards of proper cultivation and harvesting to maintain the quality of the products. Feeding, cleaning, harvesting, transferring, and other monitoring and management tasks of aquaculture farms in Sri Lanka are done manually. Therefore, it is a highly labour-intensive industry, where large-scale commercial farms require massive staff for day-to-day operations. Aquaculture is still limited in Sri Lanka due to these high production costs.

Inadequate nutrition, pathogens and adverse environmental conditions can reduce yields and product quality. Environmental and other factors within the tank can change unexpectedly and pose a threat to health, or even endanger fishing within minutes. Hence, it is essential to identify problems well in advance in order to take proactive actions to address them and prevent losses.

In addition, crucial decisions such as harvest dates, appropriate feed amount, dissolved oxygen levels, and when the water needs to be purified and the tanks cleaned, are made based on past experience, gut instinct, guesswork or small data sets collected by hand. This data could also be inaccurate, as it is common to have errors and missing information when entered manually.

Without a proper management solution that provides real-time and continuous monitoring and control, farmers cannot make timely decisions and continue to face negative consequences that could affect the viability of the farm. Shrimp farms have suffered from various diseases for many years due to improper management and quality control. Local farmers are also struggling to meet export demand because of inconsistent production and low-quality produce.

Intelligent Aquaculture

With the emergence of new technologies such as the Internet of Things (IoT), Big data, 4G/5G networks, cloud computing and artificial intelligence, the aquaculture industry is entering a new era of digitization and automation. These tools have gradually transformed traditional labour-intensive farming into automated aquaculture systems. They have significantly reduced labour demand while increasing production rates and efficiency. It is an intelligent production mode driven by data collected from a mix of sophisticated sensors and devices. These systems with robust analytics also provide unprecedented insights on how they operate now and how to achieve better outcomes and operational efficiency in the future. Besides, farmers are able to make long-term strategic decisions based on historical information using intelligent aquaculture practices.

An intelligent aquaculture system comprises the following.

1. Data collection –  Install the appropriate sensors based on the parameters you intend to measure and monitor in real-time. In general, information is collected through various temperature and humidity sensors, dissolved oxygen sensors, water quality sensors, light sensors, cameras and other digital imaging equipment.
2. Data Preprocessing – Collected data is sent to a central location via wireless communication nodes. These raw data sets need to be organized, cleaned and transformed before being fed into various dashboards, models or algorithms for decision making.
3. Real Time Data monitoring – Observe the current condition using a central dashboard as it gives an overall understanding of what is going on in the aquaculture farm.
4. Data Analytics and Decision Making – Stored preprocessed data is fed into analytical models to obtain actionable and meaningful insights and make operational decisions to increase productivity, efficiency, yield and quality and reduce costs.
5. Feedback of decisions – Intelligently and automatically execute controllable equipment such as feeders, aerators, cleaners, pumps and carry out operations independently. In addition, notify farmers when corrective actions need to be taken to maintain ideal conditions via SMS/ Email/In-app notifications.

How does it work?

Automated feeding

The feed amount depends on the fish species, its growth stage, environmental conditions and water quality. Producers should consider all of these factors in determining the optimal feed amounts and ideal feeding times. Therefore, feeding can be a complex and burdensome task especially for a large aquaculture farm that breeds multiple fish species. However, intelligent feeders take dissolved oxygen levels, water temperature and other species-specific data into consideration when making decisions. The software controls the feeders automatically to feed fish, only when required.

It eliminates the guesswork and ultimately makes feeding more efficient. Accurate feeding also ensures high production, better water quality and reduces waste of expensive fish feed. Additional algorithms also predict the feed amounts required for the near future, allowing farmers to order and purchase the correct amount well in advance.

Automated aeration and oxygen control

These intelligent systems take accurate real-time readings of dissolved oxygen levels using wireless sensors and aerate the tanks automatically to adjust the values when needed. They ensure a favourable living environment for the inhabitants and improve growth and survival rates. In addition, the system will also notify the staff using multiple alert methods when abnormal DO levels are observed.

Water quality monitoring and control

These real-time remote monitoring tools provide instant visibility into the environmental condition and composition of water. Farmers will be alerted if any anomalies are detected, along with the corrective actions that need to be taken. It helps fisheries to maintain ideal conditions for the fish, preventing disease incidences and putting them under stress.

Benefits

• Automated feeders and feed optimizations improve feed conversion ratios and eventually increase the yield and quality.
• Remote and real-time monitoring ensure fish is healthy by increasing water quality and reducing disease incidences.
• Automated control will free up labour and improve production efficiency.
• It is energy efficient as controllable equipment is utilized only when necessary.
• Real-time alerts mitigate risk and reduce losses.
• Collectively it will enable scaled-up operations and improved bottom lines.
• It also acts as a catalyst that drives aquaculture to a more efficient and profitable industry.