Birds mimic alarm calls of other species to steal food
By ANIWednesday, November 3, 2010
LONDON - A new study has discovered that drongos in the Kalahari mimic the alarm calls of other species to steal food.
The birds ‘play tricks’ on meerkats in particular, following the little mammals around until they catch a meal, reports the BBC.
The drongos then make fake alarm calls that mimic other species and cause the meerkats to run for cover, allowing the drongos to swoop in.
Scientists reported that by mimicking other species, the drongos keeps their deception ‘believable’.
“It’s a nifty trick,” said Tom Flower, the Cambridge University PhD student who carried out the research.
Flower began his work studying meerkats in the Kalahari Desert and noticed their reaction to the drongos’ alarm calls.
When a predator was in the area, the birds could make an alarm call and the meerkats would immediately dash for cover in boltholes.
“But when the drongos saw a meerkat with a large food item such as a gecko, larvae or even a scorpion, it would make a false alarm call that sounded the same as the calls they made at predators, even though there were no predators around,” said Flower.
The researcher then followed and studied the drongos, and discovered that they mimicked the alarm calls of several other species.
This appeared to persuade the meerkats that there was a dangerous predator in the area and they should abandon their food and hide.
To avoid being ignored, the birds deliberately changed the type of call they make - to alter the species they mimic - when meerkats stop responding to their alarm calls.
“This might keep their deception racket going, increasing their food stealing profit,” said Flower.
Although most of the species they impersonated were other birds, drongos even managed a meerkat alarm call.
Flower thinks the birds may have learned by trial and error that meerkats are likely to find their own alarm call ‘particularly convincing’.
“It’s very common in birds, but [previously] we had no idea why they did it,” said Flower.
The findings are reported in the journal ‘Proceedings of the Royal Society B’. (ANI)