Salmon Farms: my interpretation of what is happening
Updated: Apr 8
Sealice that do appear in wild Salmons, but are easily gotten rid off once the Salmon swims into a river and they do not pass as easily between one another as the salmon aren't kept in such close proximity. In the pens, sealice get transfered between Salmon much easier as they are a lot closer together. As well as this, farmed salmons cannot swim inot rivers to get rid of these sealice. Treating sealice in farms has lead to the use of antibiotics being fed to the salmon to get rid of the lice, which in turn obviously goes into their system, which later on will be consummed by us. As well as this, The amount of Salmon that dies in these farms is around 1/3 of each pen. If a pen has 20,000 salmon, 1/3 would be 6,666 fish. A farm has around 10-30 net pens, therefore each farm "wastes" around 66,666 - 2,000,000 fish per season. Fish decay is not necessarily a bad thing, there are a lot of benefits to fish decomposing at the bottom of the ocean such as nutritional value. However, the mass death of these fish cuase large levels of nitrogen, sulfur, carbon and phosphorus that are then transferred from the ocen to land. such large levels of these nutrients can have an impact on plant growth as the soil will become too acidic for plants to grow.
Apart from this, farm-bread salmon are much smaller and weaker than wild salmon. If salmon escape from the farm, they usually die. However, those that dont, reproduce and transfer their genes to their offsprings. This cause for the wild salmon population to diminish since the farm-bread salmon genes are much weaker, causing their offsprings to also, be weaker than pure wild salmon and die.
Salmon is the no.1 fish eaten in the UK. Its frowing demand is causing more and more salmon farms, which in conclusion is causing more environmental as well as health issues. Preventative methods have been used to fix issues in the salmon farms, however these are short term resolutions, not ideas to stop the overall problem.