Almost all the Yellow-rumps have left for breeding grounds in the north. They are a pleasure to welcome back in the garden in early fall, quite unmistakable with their yellow rump and side. A large warbler and the only one we expect in winter, often feeding on berries in the middle canopy.
They migrate in large flocks. In the spring of 2001, an estimated 34,000 were seen over Northampton county for two hours. Never here in summer, they are occasionally reported in the west of the state where they rarely stay to breed.