The number of Hooded Merganser (Lophodytes cucullatus) broods hatching in nest houses on 53 study areas in Massachusetts increased by 289% from 1979–1983 to 1994–1998 and the number of areas used increased from 9 of 53 in 1979 to 26 of 53 by 1998. The number of Hooded Mergansers counted on 21 Massachusetts Christmas Bird Count circles from 1979–1983 to 1994–1998 increased by 225%. The increasing trend lines did not match, suggesting different populations. This appears to support reports of increasing Hooded Merganser populations by other northeastern state waterfowl biologists.