Fig. 2. Population trends of ground nesters and cavity nesters, including the seven most abundant species: American Black Duck, Ring-necked Duck, Common Goldeneye, Common Merganser, and Canada Goose, Common Loon, and American Greed-winged Teal. Population sizes are IBP for the whole study area: values extrapolated from survey plots to the whole 540,000-km˛ study area; left vertical axis, and IBP/100 km˛ (right vertical axis) for the 1990–2003 period. Population trends for all species surveyed are available in Bordage et al. (2003).