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Abstract: We used 39-year datasets from the Breeding Bird Survey (BBS) and the Audubon Christmas Bird Count (CBC) to determine continental and regional population trends of 146 species of waterbirds that regularly occur in seven bird conservation regions in which more than 10 % of the land area is devoted to row crops. Thirty-nine of the species show long-term continental declines on one or a combination of the surveys; 52 species show large increases. For many of these species, CBC analyses are available for the first time. Current wetlands acreage is a fraction of what occurred 300 years ago as Europeans spread throughout the continent; however, our results show a partial recovery of waterbird populations, especially over the past 20 years. Probable contributors to this partial recovery include: 1) Banning of organochlorine pesticides and the population recovery of fish-eating birds, 2) Success of wetland and farmland conservation programs in restoring waterbird habitat, and 3) Provision of excess food to waterbirds, especially corn and rice. Although there are more increasing species than decreasing, there are nonetheless a significant number of declining species and additional species with inadequate trend information that are known to be of conservation concern. We discuss possible causes of declines and reasons for conservation concern for these species