The brown-headed cowbird is a brood parasite of the songbird. This means that it lays its eggs in the songbird's nest, and its chicks get taken care of. The cowbird only targets those songbird nests which are located on the forest edge. This is because, edges tend to be near agricultural lands, which provide the cowbird with an ample supply of insects. An increase in deforestation means that the forest edge is increasing, which has resulted in more cowbirds and lesser songbirds, especially because the former is even known to throw aside the latter's eggs to accommodate its own.
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