Meet the bird that not only cries wolf, but also benefits from sounding false alarms by stealing food when other animals flee.
In a new study, researchers detail how the African forked-tailed drongo imitates the alarm calls of other birds and even meerkats, Reuters reported. The ruse scares animals into running away, leaving the sneaky bird free to snag the food that gets left behind.
"They're rather demonic little black birds with red eyes, a hooked beak and a forked tail," evolutionary biologist Tom Flower of the University of Cape Town in South Africa told Reuters. "They're also highly aggressive and are renowned for attacking eagles and hawks, for which they apparently have no fear."
Drongos have an extensive repertoire of sounds comprising the warning calls of birds including pied babblers, glossy starlings, sociable weavers and pale chanting goshawks. They also imitate some mammals such as the meerkat.
Why do animals continue to listen? The drongo is smart enough to change up the alarm call if animals aren't running away. The medium-sized bird also sometimes uses its danger signal for legitimate purposes, making other animals trust the warning sound.
"All the animals in the Kalahari eavesdrop on each other's alarm calls, which provide invaluable information about potential predators. It's a bit of an information superhighway where all the animals speak each other's language," Flower told Reuters.
He and his team monitored 42 of the birds, which have around 51 alarm calls at their disposal, recording the sounds they made in the wild as they attempted to steal food.
Tracking the wild drongos on 151 foraging excursions, the researchers found that the drongos changed up alarm signals on 74 occasions when the first call didn't work.
"They're paying attention to their targets, and they change what they're doing based on the feedback they receive," Flower told National Geographic.