The South Bird (サウスバード Sausu Bādo?) is a species of bird native to the forests of Jaya and Skypiea. For unknown reasons, its head is always inclined south, regardless of the bird's current location or position.
In ancient times, prior to the development of log poses, some civilizations used South Birds as navigational aids.
South Birds have extremely colorful plumage, chiefly in alternating patterns of purple and green. Their heads - particularly bills - are markedly long and narrow, akin to those of toucans. Like most birds, they are tetradactyl, with three forward-facing toes and one backward-facing.
The typical Jaya specimen is roughly the size of a human toddler. However, the typical Skypiea specimen - due to generations of consuming the land's unique nutrients - is several times larger.
South Birds cannot point their heads in any other direction, even momentarily, without considerable effort. To compensate, their neck muscles are incredibly flexible, allowing them to turn and move their bodies more-or-less independently of their heads.
Their call is a deep and highly distinctive "Jyo" (ジョー?). Through unknown mechanisms, this call allows them to control a wide variety of insects, such as moths, hornets, and praying mantises.
Possibly due to a long history of being hunted and used as navigational tools, the South Birds of Jaya tend to be ill-disposed toward humans, and will not hesitate to drive nearby insects against would-be hunters. In contrast, those of Skypiea are benign enough to befriend, respect, and even rescue humans at no gain to themselves.
Sky Island Saga
On Jaya, the Straw Hats needed a south bird to find their way to the Knock-Up Stream. Mont Blanc Cricket told them they needed a south bird to act like a compass so they could navigate to the Knock-Up Stream. Nico Robin eventually caught the bird and held him for the trip to Skypiea, using her Devil Fruit power. During the voyage to the Knock-Up Stream, The South Bird tried to confuse the Straw Hats by turning its head in a different direction (but failed due it getting antsy whenever facing a direction other than south). After attacking Nami for not setting it free the south bird escaped once the crew made it to Skypiea. In a comedic twist, the south bird came back to the Going Merry. Chopper translated for the bird, stating that he did not want to stay at Skypiea. After Chapter 302, the south bird is not seen again until after the timeskip in a chapter cover.
In the anime, the south bird's role was somewhat extended to play another comedic role as he is annoyed by Vice Admiral Jonathan and attacks him in the G-8 Arc. The south bird was again unseen after that.
The south birds on Skypiea are much larger than those found on Jaya and seemingly much friendlier. Chopper, Gan Fall, and Pierre were saved from drowning by them after their encounter with Shura. Chopper learns from them that Gan Fall was the previous God of Skypiea. Later, one saved Zoro's life only so it could steal his lunch. It also laughed at Zoro for getting lost (prompting Zoro to throw his backpack at it).
Despite its friendly nature, it's not above sacrificing something at hand to save its own skin (such as when it dropped Zoro so the Giant Python would leave it alone). This variety first appeared in Chapter 251 and Episode 164.
From the Decks of the World demonstrated that there are other varieties of birds whose heads point a particular direction, and they are closely related enough for a south bird to mate with a north bird and produce eastern and western birds as a result.
- Ironically, a south bird started following Zoro, who was lost at the time and needed to go south, but was going in the opposite direction as indicated by the south bird's head pointing the other way.
- Before chapter 644's cover, the anime showed three birds where one was shown pointing east.
- These birds were possibly inspired by the magnetoreception abilities found in many real-life animals, most famously the homing pigeon.
- One Piece Manga and Anime — Vol. 27 Chapter 251 and Episode 164, The South Birds of Skypiea rescue Gan Fall, Pierre, and Tony Tony Chopper for no apparent reason other than regard for Skypiea's rightful "God."
- One Piece Manga — Vol. 65 Chapter 644, cover story: From the Decks of the World Vol. 27, North, Eastern and Western Birds are revealed.
- One Piece Anime — Episode 150, Birds are seen with their heads pointing perpendicular to each other.