The Pew Environment Group, which conducted the study, analyzed the shark meat found in 51 bowls of the traditional Chinese delicacy from 14 U.S. cities, including one from Seattle.
The researchers found meat from the school shark — also known as the soupfin shark — in the Seattle soup, a species classified as "vulnerable" by the International Union for Conservation of Nature. School shark was also found in bowls from Las Vegas, San Francisco and Orlando, Fla.
A bowl from Boston contained meat from the scalloped hammerhead, an endangered species. And soup from other cities contained such species as spiny dogfish, shortfin mako and smooth hammerhead, all considered vulnerable.