Close The world's biggest owl is endangered. Fortunately, it's not yet too late to save it. Native to Russia and parts of Asia, the Blakiston's fish owl is facing a continuous decline in population due to habitat loss and climate change. (Photo : Jonathan C. Slaght) Bubo blakistoni doerriesi found on the Russian mainland and likely northeastern China, and Bubo blakistoni blakistoni, which lives in Hokkaido, Japan, Russia's southern Kuril Islands. Rada Surmach, a Ph.D. candidate and researcher at the Federal Scientific Center of the East Asia Terrestrial Biodiversity in Vladivostok, has created a long-term conservation plan to reintroduce captive-bred fish owls to the Land of the Leopard National Park in southern Primorye. In this relatively developed region, the fish owl once lived.