thats a toughy ....but a pergrin falcon comes to mind...
based on the speed ...but scientists have determined that highways do indeed have signifgant usage as land marks used by many species to navigate with.... owls work the highways and some of the smaller ones are white colored and are incredible fliers
. there had to be some kind of pattern to the flying like dipping
~~~~ ------u----- .........'`` and that is a big clue.
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