| grassland songbirds in a dynamic management landscape: behavioral responses and management strategies. | in recent decades, earlier and more frequent harvests of agricultural grasslands have been implicated as a major cause of population declines in grassland songbirds. from 2002 to 2005, in the champlain valley of vermont and new york, usa, we studied the reproductive success of savannah sparrows (passerculus sandwichensis) and bobolinks (dolichonyx oryzivorus) on four grassland treatments: (1) early-hayed fields cut before 11 june and again in early- to mid-july; (2) middle-hayed fields cut once ... | 2006 | 17205901 |