Invasion of the Chinook

Chinook, or king salmon, largest of the five North American salmon species, reached South America some 25 years ago as people tried to farm them there, says Cristián Correa of McGill. Now a broad survey of records and stream visits finds chinook reproducing on their own in at least 10 Andean watersheds that empty into the Pacific plus more along the coast, and three Atlantic watersheds, Correa and Mart Gross report in the June Biological Invasions. Correa says he is worried that the invaders could disrupt both freshwater and marine ecosystems.