Look out, Hawaii! Open ocean aquaculture (OOA), also known as sea-cage farming, has many problems.
OOA of carnivorous fish is worse than over-fishing. Production of one pound of farmed tuna requires the oil from over 10 pounds of wild-caught fish, usually anchovies, menhaden and sardines, which are an important source of protein in Third World countries and an important source of omega-3 fatty acids in developed countries. Farmers use as much soy as they can, but tuna can't survive without fish oil.
Anchovy, menhaden and sardines are important "cleaners" of the ocean. When these plankton-eating fish are over-harvested, jellyfish are released from competition for food, and they proliferate.
Farmed carnivores have higher levels of organic pollutants than wild-caught fish of the same species, and they have lower levels of omega-3 fatty acids because farmers use as much soy as possible in their feed.
Sewage from sea-cage fish is like human sewage in its effects on the ocean. OOA supporters say that dilution is the solution, but this only pushes the problem somewhere else.
Read the complete story from The Star Advertiser.
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