"Nesting hawks defensively swoop passersby," the Arizona Game and Fish Department Tucson said in a post on Facebook. "Warn others of nests with safety tape, traffic barricades or signs guns.

Instead, they make an abrupt dive and upward swoop just before perching, which reduces the chance of a clumsy landing. Young hawks appeared to learn the behaviour though experience, improving ...

By selecting just the right speed and position from which to swoop up to the perch, the birds were already within grabbing distance of the perch when they stalled, keeping their landings as safe ...