blog posts Female cowbirds pay attention to cowbird nestling survival, study finds Sep 9, 2015 11:15 am by Diana YatesResearch Share on Facebook Tweet Email Images Brown-headed cowbirds lay their eggs in other birds’ nests and then disappear, the story goes. But a new study suggests cowbird moms pay close attention to how well their offspring do, returning to lay their eggs in the most successful host nests. Share on Facebook Tweet Email