NEW YORK — Mackerel is in but octopus is out. And bluefin tuna, known as the king of sushi for its fatty belly meat, is a definite no-no.

These tips and others on ocean-friendly sushi are now available in pocket guides being published this month by three conservation groups. The sustainability guides are the first specifically for sushi, listing fish by their Japanese and English names.

"The sushi industry as a whole is probably pretty far behind the curve," said Trevor Corson, the author of "The Story of Sushi" and a contributor to one of the guides, produced by the Blue Ocean Institute.