smew
A species of duck (Mergellus albellus). The name is usually written in katakana.
In winter, smews come to the lake.
Katakana spelling is standard for this bird name; usually written in kana.
Rare kanji form; it is rarely used.
The name likely derives from 巫女 (miko, shrine maiden) and 秋沙 (aisa, merganser), referring to the bird's plumage pattern resembling a miko's attire, but the exact origin is uncertain.