Carrion Crows in Spain thrive when they have a cuckoo in the nest

Carrion Crow chicks derive benefits from having to share their nest, researchers have found

A study in Spain has uncovered an interesting relationship between Carrion Crows and Great Spotted Cuckoos, reports Springer’s journal Behavioral Ecology and Sociobiology.

When the cuckoos lay up to three eggs in the nests of the larger crows, the chicks of both species are often raised together successfully, with the young crows ultimately growing bigger than the cuckoos.

So it’s not so bad for crow chicks as it can be for other species of birds who find their nests taken over by a cuckoo youngster.

When our Common Cuckoos utilise the nests of Reed Warblers, the growing cuckoo chick will push other eggs and chicks out of the nest.

When Great Spotted Cuckoos parasitise and take over Magpie nests, they do not evict the host’s young from the nest. They do, however, succeed in out-competing the magpie chicks for food, which often leads to the latter’s death.

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