Migration Info One of the last of the migrants to return in spring, the Eastern Wood-Pewee doesn't appear in northern forests until there are plenty of flying insects. Small numbers of this species cross the Gulf of Mexico, while the majority of individuals move up the Gulf lowlands then fan out and move through the eastern states on a broad front. This species is declining due to loss of wintering habitat in South America as well as breeding habitat in the United States. Eastern Wood-Pewees prefer forests with dense understory growth. Studies have shown that their decline in this country may be a result of destructive browsing by White-tailed Deer, whose populations are exploding in the upper Midwest and northeastern states.