The Common Cuckoo, Cuculus canorus, is a brood parasite. Female cuckoos lay their eggs in the nests of other birds (pictured here is a reed warbler) who brood the eggs and feed the young cuckoos. Cuckoo chicks monopolize their foster parents’ care by pushing their own chicks out of the nest. Cuckoos are much larger birds than their hosts, so the cuckoo chicks soon outgrow their foster parents who diligently feed them until they fledge.
More about the Common Cuckoo: Encyclopedia of Life
Image by Per Harald Olsen via Wikimedia Commons
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