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Birds pass along secret code to un-hatched chicks

Birds pass along secret code to un-hatched chicks

Before they even hatch, Superb Fairy Wren chicks are learning a secret code that means everything for their survival. The mothers of the chicks sing a special “password” note to their un-hatched chicks, which they must recite once hatched, in order to be fed. No password, no food.

It may seem a bit paranoid on the mother’s part, but there is a very good reason for them to be suspicious. That’s because Cuckoo birds have been known to secretly plant their eggs in Fairy Wren nests. Once the baby cuckoos hatch, they are fed and raised by the surrogate mother. The “pass-note” method then, helps the mother to distinguish which chicks are hers and which are cuckoos. The mother is thought to start singing the note about 10 days after the eggs are laid, giving the chicks just five days to learn it. Cuckoos often only have two days in the nest and therefore don’t have enough time to learn the note. This method isn’t quite foolproof, though. The mothers only catch the cuckoos around 40% of the time. Oftentimes the cuckoo chicks happen to sing the note by trying multiple calls.

Perhaps soon enough the Cuckoos will come up with a counter-strategy of their own for cracking the code. In the meantime, visit our website and learn how our Song Meter SM2+, accessories, Song Stream Remote Access Module and Song Scope software can make your bird call collection and analysis work faster and easier.

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