Cuckoos Lay Eggs in Warbler Nests and fly away. Should Mama Warbler raise the cuckoo baby as her own? Inspired by The Ugly Duckling by Hans Christian Anderson. This story shows mutual benefit to both warblers and cuckoos when a cuckoo lays an egg in a warbler's nest. Cuckoo babies eat six times as much as warbler babies. Soon they are bigger than their warbler mamas. They are stinky and hungry and huge. Will Mama Warbler love her new baby?