Stanford student spots 'holy grail for birders' on remote Bay Area ranch
That Thursday morning, though, Freeland noticed an unusual bird darting around in a willow tree. It had a torpedo-shaped body that was roughly the size of a large lime, and a strip of feathers above the eye resembling an eyebrow, which he recognized as belonging to an Old World warbler. Immediately, he knew what that meant: He was looking at a bird that had never been recorded in the Bay Area. Because certain warblers are some of the hardest birds in the world to tell apart, there was some debate in the group at first about what species Freeland had found. But after he captured audio of the bird's distinctive "tsu-weet" call, most everyone agreed: It had to be a yellow-browed. "For one to end up on the wrong side of the Pacific is truly astounding and insane, and it barely ever happens," Freeland told SFGATE. "So for anyone who wants to see a yellow-browed warbler, this was the moment."…