There are seven varieties of tuna you might buy: albacore, bigeye, skipjack, yellowfin, Atlantic bluefin (farmed and wild), southern bluefin (farmed and wild) and Pacific bluefin. One rule here is simple: avoid all bluefin tuna. (Tweet this) Some are critically endangered species, and even farmed bluefin have to be captured from the wild. So no bluefin. Ever.
Albacore can be sustainable, bigeye and yellowfin rarely are, so the best tuna variety to choose is generally skipjack, a fast-growing species that is still quite plentiful around the world and makes up most of the tinned tuna you will find. The problem here, however, is how it’s caught.