Threats to the Environment & Wildlife
In addition to harms posed by overfishing, aquaculture can pose imminent threats to the environment and wildlife in several ways, most notably by allowing fish to escape their facilities and invade wild habitats:
- Genetic Pollution: Specially-bred species that are ill-suited for the wild can interbreed with wild stocks and “water down” the gene pool, leading to the potential extinction of those native stocks.
- Habitat Invasion: Specially-bred species can invade natural habitats and alter both the physical geography of the ecosystem and the localized food web, competing with wild fish for space and food sources. They can also impact marine mammals that may aggregate in new locales due to the changing environment and food sources.
- Spread of Disease: Fish crammed in unsanitary conditions in aquaculture facilities are prone to infection and disease, such as infectious salmon anemia and sea lice. Diseased fish can escape and spread such pathogens to wild stocks with potentially devastating effects.
Furthermore, dumping of aquaculture facility wastes into open ocean waters can destroy fragile marine environments. Antibiotics used to prophylactically treat fish can bioaccumulate in wild marine animals and harm critical ocean bacteria, and harmful pesticides used to control sea lice and protect fish eggs can poison complex marine environments.