A study conducted for the New York Times last March found that six of the eight New York City fish vendors tested were falsely selling farm-raised salmon as wild. The story unfolded when the Times realized that many of the stores were selling "fresh" wild Pacific salmon in the fish’s off-season. People covet wild salmon because it is leaner, tastier and contains no color dyes and fewer cancer-causing polychlorinated biphenyls (PCBs) than its pen-raised cousin, according to Ecotrust’s Salmon Nation.
Infectious diseases common in farm-bred pens can spread into the surrounding waters (see "Wild and Free," Currents, November/December 1998), and interbreeding of wild and escaped farmed salmon is a threat. Farmed salmon are sometimes caught outside pens and sold as wild, fooling both the fisherman and the consumer. To be certain salmon is truly wild, try to determine your vendor’s supplier and make inquiries.