As interesting as these findings may sound, peregrine expert Glenn Stewart of the Predatory Bird Research Group believes that the authors’ explanation of stoop success fails to take into account a major factor – eyesight.
“We don’t fully understand what and how peregrines see,” Stewart told IFLScience. “A peregrine eye has two foveas – we have just one – enabling them to quickly judge speed and distance simultaneously.”
He continues that the birds’ unique eye anatomy allows them to focus on prey while keeping their head aerodynamically tucked, a trick non-raptor birds can’t perform.
Furthermore, this type of study can’t quantify the impact of acquired skill. Stewart adds: “And of course, practice-practice-practice helps them survive.”
“Young peregrines fly well but are clumsy their first day or so in the air. They chase one another, other raptors, and are known to practice in-air captures by snatching dragonflies and knocking the tops of flowers. Within just a few days they transform themselves from bumbling landings to true masters of the sky – yes in literally three days!"