Aquaculture - What & How?

 AQUACULTURE:

The word aqua should remind most of us about water. Well it’s true! But aquaculture is not just something related to water. It is the entire sum of processes involved in the breeding, raising, and harvest of aquatic organisms in a controlled environment. Generally it is done in water. So we can say that aquaculture, is farming of aquatic organisms like fish, shellfish, aquatic plants etc., in water. In the United States, aquaculture or aquafarming is a major farming practice that provides and acts as a source of food and related commercial products, protector for healthy habitats and also revival mechanism for endangered aquatic species. It is said to have originated in China somewhere around 2000 BC and gradually spread to other parts of Asia and later Europe.

    Though aquaculture is often misunderstood to be the same as fisheries or fish farming, there are differences. One can simply say that aquaculture can be a part of fisheries but fisheries is a lot more than that.

Why aquaculture?

85% of the sea fish stocks in the world have been depleted so far, as reported by BBC. This is very much alarming considering the fact that the demand for seafood has only been rising year to year. So to find an alternative to depleting our ocean reserves, we can consider aquaculture to meet this growing demand for seafood, as it is one among the most popular methods in fish farming. There are multiple benefits in adopting an aquaculture system. If managed well, it can provide a good, nutritionally sufficient source of food, uplift the coastal and rural economy and also cleanse the waterbodies naturally.

How does it work?

            The different techniques involved in a farm – to –table procedure of aquaculture can vary with each species. There are four basic steps or stages in the production of seafood, which starts from a hatchery and ends at your favourite seafood restaurant in the town. With respect to the quality and safety of seafood produced and, its impacts on the environment these stages can vary. This is pretty much the reason why the BAP certification programme (Best Aquaculture Practices) is regulated and monitored by Global Seafood Alliance. BAP is the sole certification programme that ensures coverage of all the steps in the supply chain and it serves in improving the fish farming industry of the world.

The stages:

Hatchery. This is the 1^st stage in the production chain and is where the fishes are bred and eggs are hatched and fishes are reared.

2.    On attaining of sufficient maturity these fishes are taken to a farm where they are fed & let to grow to harvestable sizes.

3.      The harvested fish are then transported to a processing unit.

4.      The packaged food products are finally sent to retail sellers and stores actively involved in the seafood business.

Different types of production systems

1.      Cage system: Makes use of cages and are placed in the waterbodies like lakes, ponds, oceans where there are fishes. Also known as off-shore cultivation, is a system where fishes kept in cages are artificially fed and harvested.

2.      Irrigation ditch or pond systems: This is an inland system where a ditch or pond that contains a considerable amount of water is used for rearing the fish at a small level. There is a self-sustaining feature attributed to this type of cultivation which is that ponds naturally has plants and algae in them which allows fishes to feed on them and the waste products from the ponds can be used as manure for agricultural lands. This is a way for increasing the revenue of a farmer.

3.      Composite fish culture: As the name suggests, this method is a mixture or combination method involving both local fish species and also imported ones. There usually might be upto 6 species of both types that co-exist in the same pond. The choice of species are such that they are compatible with each other and the competition is less. One definitely have to make this a serious factor, if he does not want his fishes to feed on each other and ruin his business.

4.      Integrated recycling systems: This is a resource recycling method, where fish wastes are recycled to provide nutrition to plants. Inside a greenhouse, a hydroponic system cultivating mostly herbs like parsley and basil is set up. Beside a hydroponic bed there will be a large plastic tank which houses the fishes. So the water from the tanks that contain the fish wastes will be circulated into the hydroponic beds and acts as a nutrient rich medium for the cultivated crops. This is by far the largest pure fish farming method by scale.

Are these production systems always healthy and good?

Overfishing is definitely a major threat to the ecosystem. Fish farming is claimed to be a solution to the overfishing problem. But most farms are still lagging behind in terms of their handling and management pose serious threats of damage to ecosystems in the form intrusion of diseases, pollutants, invasive species etc. Fish farms often rely on wild fish species like anchovies which are placed lower in the food chain hierarchy, to feed the larger carnivorous fishes. This is a significant problem as it takes almost 5 pounds of the little ones to feed a pound of the biggies. This is not necessarily easing the impact on wild populations and such overfishing has substantial consequences in the oceanic ecosystem.

Similar to other animal farms, the housing of fishes are also in crowded and cramped environments where they lack much room to move around. The intensive & commercial nature of most farms are the reasons for it. With less room these fishes are open to suffer from lesions, damage their fins and have other serious injuries. Such conditions are also hubs to a wide variety of diseases and parasite outbreaks. In order to treat this fish farmers then turn to agrochemicals and antibiotics, which in turn create toxicity in these fishes which end up in the bodies of wildlife populations and also humans. It is quite debatable as to how fish farming and seafood business and industry can be run in an ecologically sustainable yet commercially feasible manner. Research and developments in the aquaculture sector is hence highly recommended so as to revise the existing practices and come up with newer innovations and standards to acquire the above mentioned balance required for the overall well-being of humanity and the other aquatic and terrestrial life forms in this planet.