Band 8.5 model answer: advantages and disadvantages

Aquaculture has expanded so quickly that farmed salmon, shrimp and tilapia now account for over half of the seafood eaten worldwide, a shift governments frame as a solution to collapsing wild stocks such as the Grand Banks cod fishery in Canada, which has never recovered since its 1992 closure. On balance, I believe the benefits of this shift outweigh its costs, though the environmental price tag needs careful management rather than blind celebration. The clearest advantage is that fish farming relieves pressure on wild populations while stabilising food supply. Norway's salmon industry, for instance, produces over 1.3 million tonnes annually from pens rather than open ocean, allowing wild Atlantic salmon runs to be left largely untouched. Aquaculture also offers economic advantages that wild fishing cannot match: yields are predictable, prices are stable, and coastal communities in countries like Vietnam have built entire local economies around shrimp ponds, generating steadier employment than the boom-and-bust cycles of open-sea fishing. However, the disadvantages are not trivial. Densely stocked farms are prone to disease and parasite outbreaks, such as the sea lice infestations that have repeatedly forced Chilean salmon farms to use heavy doses of antibiotics, some of which leach into surrounding waters and affect wild fish. Farms built in mangrove areas, as happened extensively in Indonesia during the 1990s shrimp boom, have also destroyed natural coastal buffers, leaving communities more exposed to storm surges. These are genuine costs that campaigners are right to highlight. Yet these problems are largely management failures rather than inherent flaws in the practice itself. Countries that have introduced stricter siting rules and closed-containment systems, such as Scotland's newer land-based salmon farms, have shown that disease transmission and habitat loss can be sharply reduced. Given that wild stocks are declining regardless of what governments do next, the realistic choice is between poorly regulated aquaculture and well-regulated aquaculture, not between farming and an undisturbed ocean. In conclusion, while fish farming carries real environmental risks, its capacity to relieve pressure on depleted wild stocks and support coastal economies means its advantages outweigh its disadvantages, provided governments enforce rigorous environmental standards.