great grey owl
Refers specifically to the species Strix nebulosa. In Japanese, bird names are often written in katakana.
I saw a great grey owl in Hokkaido.
Standard katakana spelling for this bird name.
Kanji spelling is rare; the word is usually written in kana.
From 樺太 (Karafuto, 'Sakhalin') + 梟 (fukurō, 'owl'). The name reflects the owl's range, which includes Sakhalin.