DAVIS, Calif., Dec. 4 (UPI) — Birds signal each other with alarm calls when threatened, but they also may be putting the predator on notice, scientists in California said.
Birds might be telling the predator “I’ve seen you,” said Jessica Yorzinski, a graduate student in animal behavior at the University of California-Davis.
Yorzinski captured dark-eyed juncos, yellow-rumped warblers, house finches and other birds and recorded their calls for 24 hours before releasing them back into the wild, the university said in a release Thursday.
When shown a stuffed owl, the birds overall issued omnidirectional calls, suggesting they were warning other birds. The juncos, warblers and finches, however, focused their calls in the direction of the owl, suggesting their alarm calls were to warn off a predator, Yorzinski said.
Some birds projected a call in one direction while their beak was pointed in another.
“It’s like talking out of the corner of their mouths. It’s not clear how they’re accomplishing this,” Yorzinski said in the journal Proceedings of the Royal Society B.
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