"I saw my first Blakiston's fish owl in the Russian province of Primorye, a coastal talon of land hooking south into the belly of Northeast Asia . . . No scientist had seen a Blakiston's fish owl so far south in a hundred years . . . When he was just a fledgling birdwatcher, Jonathan C. Slaght had a chance encounter with one of the most mysterious birds on Earth. Bigger than any owl he knew, it looked like a small bear with decorative feathers. He...