Hungry weaver bird chicks literally sing for their supper by making uniquely recognisable calls to their parents, scientists have learned.

Their distinctive voices allow parents not only to single out their offspring in a big colony, but also to assess how hungry they are.

German and Swiss scientists studied a population of Jackson’s golden-backed weaver birds on the shores of Lake Baringo, Kenya.

The researchers temporarily removed chicks from their nests and set up cameras and microphones to record their behaviour and begging calls.

Lead researcher Hendrik Reers, from the Max Planck Institute for Ornithology in Seewiesen, Germany, said: “Weaver bird chicks have two parts to their call: a ‘whistle-like’ call followed by a ‘trill-like’ call.

“In a non-hungry state, these parts of the call are slightly different from bird to bird, and this allows the mother to identify their chicks. As the chicks get hungrier, as you might expect with any baby, the call gets louder and more energetic, but each bird still has a unique way of modifying their ‘normal’ call to an ‘I’m hungry’ call.

“These results imply that parents have to be familiar with their chicks’ begging calls in order to estimate their hunger precisely.”

The hungrier a weaver bird chick got, the more unique its call became, the scientists found. The findings are published in the online journal BMC Ecology.