Cuckoos trick other cuckoos in the race for nests

Native Australian bronze-cuckoos trick other cuckoos as they compete to take over other birds’ nests.

Australian National University researchers found the cuckoos, which invade other birds’ nests to lay their eggs, targeted species that build domed-grass nests.

The darkness inside the nest made it hard for other invading cuckoos to see the first cuckoo eggs, which are dark-coloured.

Researchers used models of different-coloured eggs to study cuckoo behaviour and found the cuckoos were more likely to evict light-coloured eggs, namely the natural host eggs.

Previous studies have focussed on the ways cuckoos trick their hosts, rather than other cuckoos.

The findings, which were published in journal Proceedings B, give new insights into how the deceptive habits of cuckoos have evolved.

Read more at Australian National University