As the aquaculture sector continues to expand rapidly around the world, its environmental consequences are also increasing even environmentally sustainable fish farming is getting a big concerning issue for our planet. Wild salmon and other fish species are being displaced by farmed salmon, while vast amounts of aquaculture sludge are adversely impacting coral reefs and other natural habitats.
It’s no secret that the world’s natural fish stocks are in a poor situation because of excessive water pollution, and low levels of oxygen in oceans. Some statistics speculated that by 2048 there will be no fish left in our ocean. Traditional aquaculture has become a volatile industry.
Subsequently, the oxygen levels in our oceans have also decreased. Some scientists have even speculated that by 2048 there will be no fish left at all. So, could farmed fish be the solution?
Fortunately, today’s progressive aquaculture operators have the knowledge, the aquatic technology, and the commitment to reduce the environmental impacts of their operations even using artificial intelligence in aquaculture to analyze big data. By using sustainable practices, they are striving to create a more sustainable aquaculture industry.
Here we are going to describe just seven steps for environmentally sustainable fish farming which is much more important in the twenty-first century.
Steps for Environmentally Sustainable Fish Farming
1. A Proper Business Plan
A perfect plan is essential for a sustainable fish farm. It is important to have a plan that outlines all the necessary steps to ensure that the fish farm remains profitable and sustainable. An effective plan should include goals and objectives, a timeline, budgeting, and a strategy for success.
The goals and objectives of the plan should include the desired production level of fish, the quality of fish produced, and the desired profit margin. The timeline should include the length of time it will take to reach the desired production level, the timeline for achieving the desired quality of the product, and the timeline for reaching the desired profit margin. It is also important to create a budget that covers the costs associated with running the fish farm such as feed, equipment, and labor.
The strategy for success should be based on research and data that is collected from the fish farm. This includes data on the current production level, the quality of the product, the cost of production, and market trends. This data can be used to create an effective strategy to increase production and quality while decreasing costs. By understanding the data, it is possible to create a plan that will make the fish farm profitable and sustainable.
A perfect plan is essential for a sustainable fish farm. It provides the roadmap for achieving the desired goals and objectives, outlines the budget, and provides a strategy for success. Without a perfect plan, it is difficult to ensure that the fish farm is profitable and sustainable.
2. Choose The Right Species
As we know, invasive non-native species are plants and animals that are not native to a particular location and can spread rapidly, leading to a depletion of resources for native species. These species can eventually outcompete and replace native species, or even hybridize with them.
The effects of non-native fish species on native fish populations are far-reaching and costly. In many countries, the highly adaptable tilapia has replaced native freshwater species in tropical areas, while in colder climates, escaped salmon have crowded out native salmon species. A study conducted in the United States reported that economic losses caused by escaped exotic fish amount to nearly $5.4 billion annually. Similar investigations in other parts of the world have reached the same conclusion.
Native species often perform better than exotic species, as they have adapted traits and habits that are better suited to local ecosystems. People from a certain region often prefer native species as they are familiar and traditionally consumed, meaning that farmers can fetch higher prices for them. This gives farmers an incentive to choose native species over exotic ones. As Hoevenaars explains, in Zambia, the Fisheries Act states that tilapia species can only be cultured if this species is present in receiving waters, and recommends that farmers stock only native species.
3. Select A Suitable Farm Site
When establishing a new farm, it is important to avoid sites that are environmentally sensitive, such as swamps, coral reefs, or mangrove forests. Clearing and converting these areas into fish ponds would have a drastic effect on the local biodiversity. Additionally, farm effluents would eventually lead to eutrophication, a process in which excessive nutrients cloud the water and block out sunlight, thus negatively impacting the growth of plants and other marine life. Therefore, it is essential that environmentally sensitive areas are avoided when selecting a site for a new farm.
By avoiding swamps and coastal mangrove areas, one can reduce the risk of flooding and mitigate the health risks posed by mosquitoes to farm workers.
According to Hoevenaars, Zambia’s “dambo” areas, which are typically situated in low-lying swamps and often below flood level, are not suitable for fish farming as they are highly prone to flooding. These areas have ponds that are not drainable as they are constantly supplied with water from below the surface.
If you do not have the financial resources to purchase the highest quality equipment, it is best to select a sheltered area that is sheltered from large waves when choosing sites for marine cages. This is because storms can cause immense damage to expensive and difficult-to-repair pens and cages. Therefore, locations that are exposed and vulnerable to strong storms should be avoided.
4. Farm Design And Layout
The hazardous effects of untreated wastewater from traditional fish farms, especially pond farms, on the environment, the surrounding communities, and neighboring farms are a major cause for concern. The release of untreated wastewater has the potential to pollute public canals, which are used for drinking, bathing, and cleaning utensils, causing health risks to the local population. Furthermore, pathogens can spread rapidly from one farm to another, putting other fish farms in the area at risk of contamination.
Designing pond operations that treat and recycle water can provide numerous benefits. To achieve this, extra ponds can be set aside for water treatment. A settling pond, for instance, enables solids to collect at the bottom. Additionally, filter feeders such as bivalves or plants like mangroves can clean the water, while wood chips can eliminate nitrates in excess. If necessary, chemicals can be used to remove pathogens. Before disposal, discharged wastewater must also go through a similar treatment process.
A biofloc system can be an effective addition to the previously suggested solution, as it helps to convert waste materials like uneaten feeds and faeces are converted to feed fish and shrimp, thereby reducing waste output and decreasing feed costs. Moreover, this system can potentially increase farm productivity by up to 20 percent.
By implementing sustainable practices, farmers can not only promote environmental sustainability but also benefit their financial performance. Through reduced water usage and improved biosecurity, the potential for disease outbreaks is minimized, leading to greater cost savings for the farm. In the long term, carefully planned and designed farms will yield dividends for both the farmers and the environment.
5. Manage Feeding Practices
Feeds are the main source of waste in and around fish farms. When feed, such as trash fish or low-quality pellets, is not consumed, it sinks to the bottom and contaminates the water. This can lead to a decrease in the quality of the water, not only for the fish but for the environment surrounding the fish farm as well.
When it comes to fish feeding, the quality of the pellets and their suitability for a given species is of utmost importance. Low-grade feed pellets with an excessively high protein content can result in high levels of unused nutrients ending up in the faeces, which can pollute the water the fish live in. For this reason, it is recommended to use only high-quality feed pellets specifically designed for the species. Not only does this create less water pollution, but it also results in better growth rates and improved health, thus increasing farm performance.
Hoevenaars notes that many small-scale farmers in Africa and Asia still rely on single-ingredient sources such as rice bran or even kitchen waste to feed their fish. However, in Zambia, there have been initiatives to distribute quality pellet feeds to these farmers, and the governments of several countries in Southeast Asia have begun providing training in good aquaculture practices to further encourage the usage of quality pellet feeds in the sector.
The excessive feeding of livestock by farmers is not only costly, but it can also significantly contribute to water pollution. It is therefore essential that farmers practice mindful feeding in order to reduce both their expenditure and the amount of pollution in our water systems.
Good feeding practices can help prevent excessive waste and optimize the water quality and health of farmed fish, thus reducing the weakening of their immune systems and preventing high mortality and slow growth rates.
6. Minimise Chemicals And Veterinary Drugs
Farmers often use chemicals to prepare ponds by eliminating predators and snails, as well as to maintain water quality. Additionally, veterinary drugs may be employed to keep fish healthy or to treat sick batches.
The undeniable truth is that most of these chemicals enter the public water supply. When farm runoff is released, these potentially lethal chemicals and veterinary medicines can end up in the environment near the farm. Just consider: if they were created to kill snails and bugs in ponds, they will likely have the same effect on rivers and lakes.
By having an understanding of best farming practices and utilizing natural alternatives, the need for chemical treatments can be eliminated. It is much better to treat any ill fish in an isolated, quarantined tank so that the chemicals used will not be released into the natural environment.
Hoevenaars explains that the guide for smallholders in Zambia recommends four measures to keep fish healthy and reduce the need for veterinary medicines: stocking healthy seed, using clean water, avoiding stress through appropriate stocking densities, regular feeding, and careful handling; and ensuring regular sampling and observations to check for signs of diseases.
7. Plant Native Vegetation
In conclusion, planting trees around your farm is beneficial in many ways. Not only do they provide shade, they also reduce the effects of wind and offer an additional source of food for humans, fish, birds, and other creatures.
As aquatic weeds provide natural shelter for both vectors and predators, and weeds on the pond dykes and dense vegetation near the pond will be hiding places for predators and other unexpected animals. So it should also be noticed that for biosecurity purposes the pond and immediately adjacent areas must be kept clear of vegetation
In addition, planting in the right location and season is important to ensure that your trees and plants stay healthy and thrive. Consider the natural conditions of your area such as soil type, average temperature, amount of sunlight, and water availability. Planting during the optimal season for your area will also help to ensure that your plants and trees get off to a good start, and will increase the chances of them surviving and thriving for years to come.
Through these seven tips, we hope to help today’s generation of forward-thinking modern fish farmers produce more seafood sustainably. By implementing sustainable fish farming practices, the demand for daily consumption levels can be met in a way that is better for the environment. These practices include reducing the use of chemicals, controlling the amount of feed given to fish, and carefully monitoring water quality.
In addition, fish farms should be designed and managed in such a way that they do not disrupt the natural habitats of wild fish species. By implementing these measures, fish farms can become more eco-friendly and help to preserve the aquatic environment for future generations.