Ever since coming to New Zealand on vacation for five weeks on February 23, I have been eating a lot of the country's wonderful fish and seafood. Everything from the well-known salmon, prawns, shrimp, oysters, and calamari to butterfish, groper, smooth dory, gurnard, ling, monkfish, and blue cod and on to fish I never heard of before -- hoki, moki, warehou, tarakihi, whitebait, bluenose, trumpeter, and green shell mussels. We have a greater variety of fish and any other source of omega-3 fats,...