The wood thrush makes its nest in woodlands in the northern and eastern United States. As patches of woods become smaller, increasing numbers of wood thrush nests have eggs laid in them by the brown-headed cowbird. Cowbirds live in open fields and are nest parasites; the female cowbird flies up to an unattended nest, quickly lays an egg in another birdʹs nest, and leaves the host parents to raise their ʺadoptedʺ young. Wood thrushes are decreasing in numbers because _______________.

Question

Quizplus · Accepted Answer

Habitat fragmentation creates smaller patches of woodlands, which makes it easier for cowbird parasitism to occur because there are fewer nesting options for wood thrushes. This means that the cowbirds are laying more eggs in wood thrush nests, leading to a decrease in wood thrush populations.

The Wood Thrush Makes Its Nest in Woodlands in the Northern