Population status of North American grassland birds from the North American Breeding Bird Survey
We summarize population trends for grassland birds from 1966 to 1996 using data from the North American Breeding Bird Survey. Collectively, grassland birds showed the smallest percentage of species that increased of any Breeding Bird Survey bird group, and population declines prevailed throughout most of North America. Although 3 grassland bird species experienced significant population increases between 1966 and 1996, 13 species declined significantly and 9 exhibited non-significant trend estimates. We summarize the temporal and geographic patterns of the trends for grassland bird species and discuss factors that have contributed to these trends.
|Population status of North American grassland birds from the North American Breeding Bird Survey
|B. Peterjohn, J.R. Sauer
|USGS Publications Warehouse
|Patuxent Wildlife Research Center