cockatoo
Refers to the bird family Cacatuidae. The kanji form 巴丹 is ateji.
I saw a white cockatoo at the zoo.
Katakana spelling, common for animal names.
The reading ばたん likely derives from English 'cockatoo' via Malay 'kakatua' or Dutch 'kaketoe', with the kanji 巴丹 used as ateji.