The cattle_egret, a species widely distributed in Africa, Eurasia, and
   Australia,  was not found in the Americas 200 years ago. Some of these
   strongflying  birds  managed  to  fly  across  the  Atlantic Ocean and
   colonize  northeastern South America in the late 1800s. They gradually
   spread  northward  into  North America, reaching Florida in the 1950s.
   Today  they breed as far west as the Pacific Coast and as far north as
   southern Canada. 1