Camera-wearing falcons reveal hunting strategy
'Motion camouflage' tactic used to stalk prey, study finds
Falcons wearing tiny cameras are giving scientists a dizzying glimpse into the predators' aerial hunting tactics.
In an interview airing Saturday, physicist Suzanne Amador Kane tells CBC Radio's Quirks & Quarks how she analyzed falcon hunting strategies mid-flight and in three dimensions.
"In order to get a sense of what the falcons were seeing, we used miniaturized video cameras small enough to mount on little helmets or little backpacks," said Kane, an associate professor of physics and astronomy at Haverford College in Pennsylvania.
Using a video camera the size of a USB key, Kane watched the mid-air, dogfight-style pursuits.
Targeting prey's 'future position'
The falcon's excellent peripheral vision allows them to give chase with a "predictive strategy," she said.
"Falcons have found a way to figure out where the prey will be in the future rather than where they see it at the present," said Kane. "They target the prey so it's constantly at an angle in their visual field, and that constant angle corresponds to the angle that will allow them to fly towards the prey's future position."
The manoeuvres are so effective because falcons appear to use a "motion camouflage trick" in which the falcon keeps a fixed position on the side of its prey, making it appear motionless during the pursuit.
From the prey's point of view, she said, the falcon's approach would be masked and gradually "loom larger as the two get closer together."
Kane's research is published in the Journal of Experimental Biology.
You can listen to the full interview Saturday at noon on CBC Radio One.