Quoted: According to neurologist Lauren Riters of the University of Wisconsin, starlings have among the longest and most complex songs of any birds in North America. They continually incorporate new sounds into their vocal arrangements, often mimicking frogs, goats, cats and even other birds. The result is an admixture: warbles, creaks, squeaks, whistles, throaty chirrups, twitters and raspy trills.
While singing, the starling syrinx vibrates in two separate parts, which allow one bird to sing harmonizing duets with itself. “Starlings sing because it makes them feel good,” Riters explains.