Seafood Watch - Seafood Guide


© Monterey Bay Aquarium
Opah Avoid: Avoid these products for now. These fish come from sources that are overfished or fished or farmed in ways that harm the environment. Moonfish Imported Longline
Opah Good Alternative: These are good alternatives to the best choices column. There are some concerns with how they are fished or farmed – or with the health of their habitats due to other human impacts. Moonfish Hawaii Longline

Opah, Longline, Hawaii or Imported

Opah is not targeted by any major commercial fishery, but is caught accidentally in longline fisheries that target tuna, mahi mahi and other valuable open ocean fishes.

Consumer Note

Opah, also referred to as moonfish, is sold both fresh and frozen and can also be found prepared as sashimi.

Health Alert

Environmental Defense Fund has issued a consumption advisory for opah due to high levels of mercury.


There is considerable concern about the amount and type of accidental bycatch from longlining. Longline fisheries kill sea turtles, seabirds, protected and endangered marine mammals, as well as other vulnerable fishes like sharks and rays. Managers and fishermen in the U.S. fleet have made great strides in reducing interactions in recent years through changes in regulations and modifications to longline fishing gear.

International longline fishing fleets, however, may not adopt such precautionary measures. For this reason, consumers should "Avoid" imported opah, while opah caught by U.S. fisheries is a "Good Alternative."

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How fish are caught or farmed makes a difference. Fishing boat