This has never been recorded and is most likely another conduct, say researchers.
Zoologists at the University of Cambridge recorded a gathering of mallard ducks chasing different flying creatures on a repository in Romania.
Two youngsters – a dark wagtail and a dark redstart – were pursued and gulped when they arrived in the water.
Mallards are a standout amongst the richest sorts of wild duck, and a typical sight in parks and on lakes.
The duck regularly snacks on seeds, oak seeds, berries, plants and creepy crawlies.
It has, on events, been believed to eat little fish, however greater vertebrates are ordinarily entirely off the menu.
Dr Silviu Petrovan saw the strange conduct of a gathering of mallards while he was out winged animal viewing with companions close to a national stop in southwest Romania.
He saw the grown-up female duck snatch the dark wagtail in her nose, and over and over submerge it in the water, before in the long run eating it.
A moment winged creature – a youngster dark redstart – then arrived in the water, where it was pursued by adolescent mallard ducks.
“The poor winged creature arrived on the water and was shouting and attempting to explore itself out of risk,” said Dr Petrovan. “At that point it was quickly assaulted by the mallards.”
The flying creature in the end vanished – thought to be suffocated or devoured.
The researchers could discover no record of mallard flying creature predation in the logical writing, which recommends such conduct is both “exceptionally uncommon” and recently learned.
“The mallard was hugely attempting to eat that wagtail, apparently on the grounds that it couldn’t really shred it in light of the fact that the bill is smoothed – it’s not intended for tearing prey separated,” said Dr Petrovan.
“Processing bones and plumes – that is not something that mallards have truly advanced to do.”
Ducks by nature are at times forceful and tend not to appreciate novel nourishment.
Nonetheless, mallards in California have been believed to enter the ocean to eat sand crabs, maybe to discover new wellsprings of high-vitality protein.
The same might be going on at the store, which is to a great extent profound water.
“Conceivably there is a considerable amount of weight for those quickly developing adolescents to get creature protein consumption, and accordingly they are taking a gander at chances to supplement that,” said Dr Petrovan.
“Be that as it may, the way that these people appear to have learnt how to chase winged animals is truly exceptional.”
The discoveries are distributed in the diary, Waterbirds.