By far one of the most popular fish consumed worldwide, salmon have been introduced around the world, occasionally reaching invasive status. But not all salmon are created equal. Below, guest contributor Peter Levi discusses options for sustainable salmon consumption. Peter is a PhD student at the University of Notre Dame whose research focuses on the influence of annual salmon migrations and watershed disturbance on stream ecosystem function.
The many species of salmon
There are seven species of Pacific salmon, five of which spawn in streams and lakes of North America. These five species have two common names each, which can lead to some confusion (but see table below). The genus, Oncorhynchus, also includes Steelhead and cutthroat trout.
|Common names||Scientific name||Available in Grocery|
|King, Chinook||O. tshawytscha||Fresh fillets, smoked|
|Sockeye, Red||O. nerka||Fresh, smoked, frozen|
|Coho, Silver||O. kisutch||Smoked, frozen|
|Pink, Humpback||O. gorbuscha||Canned|
|Chum, Dog||O. keta||Canned|
Atlantic salmon (Salmo salar) are listed as an endangered species in the United States and Canada. Despite the listing, Atlantic salmon appear on many menus and fish markets due to their popularity as a farm-raised fish.
Wild-caught vs. farm-raised: it’s all in the label
Salmon are a sustainable fish…for the most part. Salmon are often well-stocked in grocery stores, from fresh fillets and vacuum-sealed smoked fillets to canned and frozen. With several species available, being an informed consumer can ensure the salmon fishery continues to be sustainable.
Wild-caught salmon are considered to be the most responsible consumer choice. Any of the five Pacific salmon species may be wild-caught. Note that the labels in grocery stores read “wild-caught” and not simply “wild”. The natural populations of salmon in the Pacific Northwest, British Columbia, and Alaska are intensively managed and supplemented by hatchery-raised salmon (king, sockeye, and coho). Hatcheries release juvenile salmon into nearby streams and they travel to the ocean, similarly to naturally-spawned salmon. There is no way to distinguish between the millions of Pacific salmon that were born in a hatchery versus the wild
Farm-raised salmon are very popular, and their market has been growing along with many other forms of aquaculture in the previous two decades (e.g., shrimp, tilapia). Since Atlantic salmon are endangered in the US, the fillets on the market are farm-raised. However, many of these farms are located in the waters off Chile in the Pacific Ocean. Escaped Atlantic salmon have caused damage to Pacific salmon species and has the potential to establish as an invasive species.
Introduced Pacific salmon also occur in several places around the globe, including the Great Lakes. King and coho salmon were introduced to the Great Lakes in the 1960s to foster a sport-fishing industry. The populations are maintained with annual stocking, similar to the wild populations in the Pacific. Pink salmon also exist in the Great Lakes as an invasive species from an accidental introduction.
As informed eaters, we can choose salmon and other fish species to minimize extinction risk, environmental damage, and by-catch. For information on salmon and which other fish species are the most responsible dining choices, check out the Monterey Bay Aquarium’s Seafood Watch.