Many species of cuckoos are known to leave their eggs in other nests, so that their young will be raised by an entirely different bird species.
In recent observations, scientists believed cuckoos typically wait for an opportunity to leave their eggs in another nest, which means the mother bird is not in the nest.
However, a new study in the Ethology journal by University of Granada researchers found that great spotted cuckoos lay its eggs in the nest of magpies, while the magpie was sitting on it.
Smithsonian Mag has reported that scientists concluded that magpies might have been irritated raising the cuckoo birds and started sitting on their nests more these days and incubated their own eggs. However, this defensive act is not working out well for them.
It appears like the cuckoos called the magpie’s bluff and just laid their eggs inside the nest, even when the magpie’s still there.
Magpies are fighting back with some violent pecking, but in every single time, the cuckoo manages to lay her eggs in the nest, according to the report.