sentences:  Adults who bred in northeastern Hudson Bay area of Canada reached their wintering grounds, which range from central Michigan to southern Pennsylvania to northeastern Alabama, in 26 to 40 days, with arrival dates from November to early December.The departure dates from wintering grounds are variable.In southwestern Canada, they leave their wintering grounds by 6 April to 8 May (the mean being 21 April); in southwestern Idaho, wintering birds leave from 20 March to 13 April (mean of 29 March); and in the Southwestern United States, wintering birds may depart by early March.