Erratum.
In the News & Comment article "The Chesapeake Bay's difficult comeback" by Marjorie Sun (15 Aug., p. 715), the size of the Bay was reported incorrectly to be 64,000 square miles. It is the Bay's watershed that spans 64,000 square miles. The Bay itself covers more than 2,500 square miles of surface area, according to Environmnental Protection Agency figures.