Two images, one each of Mr. and Mrs. Brown-heaed Cowbird.
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The cowbirds do not build a nest, but the female usually places one egg in the nests of finches, warblers, vireos or other small song birds.
These eggs are then incubated by the host bird and after hatching, the young cowbird starves and crowds out the other nestlings by monopolizing the food supplied by the host birds.

Top Image: Mr Cowbird.


Mrs. Cowbird.