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Ocean Conservation Namibia
Informationskampagne
zu Aquakultur
All about Fish Farming
If you are eating seafood, it is very likely that the fish you had for lunch came from a fish farm. Aquaculture, or fish farming, is booming all over the world because of increasing global demand for seafood, with salmon, tilapia, carp, catfish and shrimp leading the charge. Once celebrated as the solution to overfishing, many countries are in the process of shutting aquaculture down due to severe ecological concerns. We’re dedicating our next social media awareness campaign to the dangers and threats of fish farming – stay tuned for our upcoming posts!
What is fish farming?
Fish farming, a form of aquaculture, describes the highly organised and bioengineered process of raising fish in saltwater or freshwater enclosures to be sold for profit.
What is Fish Farming?
Fish farming is done in natural ponds, rivers, oceans, as well as land-based artificial tanks and lakes.
What is Fish Farming?
In 2022, the global aquaculture industry was valued at 300 billion USD with an annual growth rate of 5%.
What is Fish Farming?
Fish farming is one of the fastest growing industries in the world.
How does fish farming work?
Fish farming starts in so-called hatcheries where fish eggs are hatched and raised in large laboratories under controlled conditions until they're big enough to be added to bigger enclosures to grow to size. Some fish farmers catch wild hatchlings and juveniles from natural rivers, lakes, or oceans to grow them into more profitable commodities. Depending on the species, they are being fed pellets, fish meal, live food, and supplements including growth hormones, until they have gained enough value and are ready to be harvested. On paper, it’s a perfect system.
Aqua culture has not solved overfishing, but instead has created major problems with wastewater, pesticides, diseases, and invasive species.
Aqua culture has not solved overfishing, but instead has created major problems with wastewater, pesticides, diseases, and invasive species.
Is fish farming stopping overfishing?
Is fish farming stopping overfishing:
In short: no. Aquaculture is not stopping conventional fishing and the same species continue to be overfished beyond sustainable levels. Almost 90% of global fish stocks are exploited or overfished! Additionally, fish farmers need krill, anchovies and other fish of lower commercial value to feed larger farmed fish. So – rather than easing the impact on wild populations - we’re killing lots of wild fish to feed the ‘more desirable’ fish we want to eat.
In short: no. Aquaculture is not stopping conventional fishing and the same species continue to be overfished beyond sustainable levels. Almost 90% of global fish stocks are exploited or overfished! Additionally, fish farmers need krill, anchovies and other fish of lower commercial value to feed larger farmed fish. So – rather than easing the impact on wild populations - we’re killing lots of wild fish to feed the ‘more desirable’ fish we want to eat.
Spread of Diseases and Parasites in Fish Farms
Fish farmers will put as many fish in one enclosure as they legally can, like batteries for chicken. Thousands of fish or even more are cramped together in small areas, a perfect breeding ground for diseases and parasites, especially sea lice, and fungal, viral and bacterial diseases. In open-pen fish farms, those diseases spread to native fish populations and destroy the local ecosystem with devastating impacts to other species. Fish diseases can occur naturally in the wild, but their effects often go unnoticed because dead fish quickly become prey. In cramped enclosures, this natural mechanism is absent.
Pesticides Used in Fish Farming
To prevent the spread of diseases, fish farmers use a wide range of pesticides and antibiotics. Farmers cannot treat individual animals. Instead, large quantities of those chemicals are poured into ocean pens and consequently, the open ocean. Wastewater flushed from land-based facilities also contains pesticides. These chemicals create so called “dead zones” with fatal consequences to native fish species and populations. Those dead zones are a major reason why developed countries are moving their fish farms to the less regulated developing countries, including Namibia! While fish was once considered a healthy meal choice, farmed fish cannot be considered organic or sustainable.
Wastewater from Fish Farms
The unusually high concentration of fish leads to contamination from feces, uneaten food, and dead fish. Open pen farms have no barriers to the open ocean or rivers, and waste products are flushed untreated into the surrounding waters. The same goes for wastewater from land-based fish farms, which often get directed into a nearby ocean or river. This contamination is called eutrophication.
Eutrophication
When wastewater from fish farms gets dumped into the ocean or lake, a process called ‘eutrophication' occurs. The water becomes too enriched with nutrients, which leads to excessive plant and algae growth, known as algal blooms. You can see when algae take over because the water turns green or brown or red. Algal blooms are part of nature, and we sometimes see them in Walvis Bay, but they happen a lot more often and more seriously around fish farms. Algal bloom causes low oxygen levels and blocks sunlight, it even clogs fish gills. In short: it kills everything.
Habitat loss
Commercial fish farms choose the same prime locations for their operation as marine animals, meaning they both compete for the same breeding and feeding grounds. Huge areas in sensitive and ecologically important habitats need to be cleared to make space. Fish farms change natural currents and take natural habitats away from local flora and fauna. Mangroves need a special mention: shrimp farming has emerged as the primary reason for mangrove destruction and deforestation globally.
Fish spills
Each single enclosure within a commercial fish farm can carry hundreds of thousands of farmed fish. Fish spills, meaning hundreds of thousands of fish escape from their enclosure at once, occur when a net pen ruptures due to corrosion, weather, lack of maintenance or negligence. It is impossible to reverse a fish spill. The escaped fish put local marine life at risk as they are competing for the same limited resources to survive. In case of escaped predators like tuna and salmon, smaller sized fish will be wiped out completely.
Escaped Fish
800.000 escaped farmed fish in Chile became invasive predators, spread disease, and disrupted local ecosystems and fisheries — a major environmental concern.
300.000 escaped Salmon in Washington State, US
In August 2017, a net pen operated by Cooke Aquaculture collapsed near Cypress Island in Puget Sound. In 2018, Washington State passed legislation to ban farming of non-native finfish (like Atlantic salmon) in state waters. Existing leases were phased out, and by 2022, Cooke Aquaculture had to end its Atlantic salmon operations in Puget Sound.
Infrastructure Causes Entanglement for Marine Animals
Open-pen fish farms are usually anchored to the ocean floor, held up by buoys and other flotation devices, and connected by walkways, tubing, ropes, or other infrastructure, creating a permanent risk of entanglement, especially when they pose a barrier to natural migrations. Once corrosion, saltwater, bad weather and tides break down the fish farm’s infrastructure, those ropes and nets and other debris turn into ocean rubbish. Some abandoned aquafarms even leave ropes and anchors behind, putting many future generations of marine animals at risk of entanglement.
The OCN team saw the reality of this risk firsthand when a stressed and panicking whale had to be rescued from a rope that was left behind at an abandoned oyster farm in Walvis Bay! The image shown is of a whale who wasn't lucky enough to be saved.
The OCN team saw the reality of this risk firsthand when a stressed and panicking whale had to be rescued from a rope that was left behind at an abandoned oyster farm in Walvis Bay! The image shown is of a whale who wasn't lucky enough to be saved.
Predators: a Welfare Issue
Fish farms attract predators including birds, marine mammals and fish who will use all their skills to try and break into an enclosure full of their favorite food. The constant sight or even the threat of predators causes farmed fish to remain in a state of constant stress making them more susceptible to diseases. If a predator enters an enclosure, farmed fish cannot protect themselves, they are exposed to injuries and death. To scare away predators, fish farmers use deterrents such as bombs, bean bullets or loud crackers, which cause even more stress among the caged fish. At the same time, predators are exposed to potential entanglement and diseases.
Fish Farming and the Environment - Big Operations are Moving to the Global South!
Many developed nations are implementing strict policies surrounding fish farming or banning the practice altogether due to its devastating environmental impacts. What do investors do now? They move their operations to countries with less rules and enforcement, with the promise of economic development, food security and jobs. We'll explore in the following posts that profits rarely trickle down to the local communities. Instead, they are the ones who are exposed to pollution, ecological destruction and other negative impacts of fish farming.
Will Fish Farming bring Jobs?
Global fish farm operations flock to developing countries with the promise of new jobs. But the advanced technology of fish farming is allowing much of the production system to be automated and only a few, usually less desirable positions are available for locals. As always, most high paying jobs go to foreigners. Instead, traditional fishermen might get pushed out of the market if farmed fish becomes available locally, or if their traditional fishing ground is taken over by commercial fish farms. Even worse – fish farms can have a devastating impact on jobs in tourism when they destroy well-known landscapes that are popular with tourists. Are fish farms a solution for job creation? No, they might even worsen the local unemployment crisis.
Senegal and Chile - Two Case Studies
Chile and Senegal are both experiencing dramatic negative impacts of fish farming in their countries. It should be a warning for other nations who are looking for solutions to fight unemployment and food insecurity.
Lake Victoria - Another example of fish farming gone wrong!
When Nile perch was introduced into Lake Victoria, it caused ecological collapse by preying on hundreds of native cichlid species, many of which went extinct.
Land-based Fish Farming
Land-based fish farming avoids some of the issues discussed in our recent social media posts, but it comes with its own challenges. Large commercial fish farms require a lot of water and energy for their feeding, cooling and storing processes. Land-based tanks must be temperature and water-quality regulated 24/7, and wastewater is often directed into the ocean, rivers or lakes.
Ocean-based and land-based fish farming have one major issue in common with the global meat industry: they rely on manufactured animal feeds like soy or fish meal, which has a major impact on global fish stocks, deforestation and climate change.
Ocean-based and land-based fish farming have one major issue in common with the global meat industry: they rely on manufactured animal feeds like soy or fish meal, which has a major impact on global fish stocks, deforestation and climate change.
Eating Farmed fish
Fish is regarded as a sustainable source of protein and a healthy alternative to meat. But more than half of the globally consumed fish are no longer caught wild, they come from large commercial fish farms where fish are exposed to pesticides and antibiotics. Farmed fish are the equivalent of battery chickens.
Large commercial fish farms contribute to overfishing and ocean pollution, and they reduce global food security and employment. The world's appetite for seafood buffets and all-you-can-eat sushi is destroying our oceans. But there is good news too: it is still possible for our oceans to recover. For that, we must change our eating habits. We say: Skip The Fish!
Large commercial fish farms contribute to overfishing and ocean pollution, and they reduce global food security and employment. The world's appetite for seafood buffets and all-you-can-eat sushi is destroying our oceans. But there is good news too: it is still possible for our oceans to recover. For that, we must change our eating habits. We say: Skip The Fish!
Would Fish Farming Reduce Ocean Plastic?
In short: no. Fish farming relies on fishmeal, which is produced from small, open-ocean fish such as anchovies, herring, sardines, and mackerel. Large amounts of fish must be caught to feed farmed fish and the ghost fishing gear crisis could even worsen! On top of that, ocean-based farms use nets and various plastic materials for their infrastructure, some of them will inevitably end up polluting the oceans.
Future of Fish Farming
It is projected that by 2030, over 60% of the world’s seafood will be farmed. Global governing agencies have called for better management of fish farms and more research on sustainable practices. But instead of working towards responsible and sustainable fish farming, large commercial fish farms move their operations to less regulated countries, including Namibia. The negative impacts of fish farming are well documented, but usually ignored and moved out of sight. Please give the ocean a voice and reconsider what you put on your plate!
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Der Ocean Conservation Namibia Trust ist eine beim Obersten Gerichtshof Namibias eingetragene gemeinnützige Stiftung.
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