Karoo

Carue, also spelled "Karoo", is Vivi's pet spot-billed duck, a fast-footed riding bird (one of the fastest modes of transportation available in Arabasta).

Appearance
Carue is a large, yellow duck. His wings are tipped with black (though not always present), as are his tail feathers. As the name implies, he has a spot on his bill. He wears a blue chullo with a white pattern on it. He also wears pink goggles with blue lenses. During the travels in Arabasta, he carried a barrel of water around his neck, complete with a straw sticking out of it.

Personality
Carue is very loyal to Vivi as well as to her friends the Straw-Hats. He acts very unique as he does sometimes exactly what he is told, like giving his hand, or doing exactly something opposite like drinking all his water although Vivi tells him to conserve his water in the desert.

His role during Vivi's time with the Straw Hat Pirates is mostly that of comic relief, although he does relay valuable information to Chopper from time to time, helps Luffy and Usopp to defeat the Baroque Works agents in Little Garden and saves Vivi from Mr. 2 Bon Kurei in Arabasta. He is the center of several jokes in the Arabasta arc, at one point being used as bait for fishing by Luffy and Usopp to Vivi's anger and chagrin, and he is mistaken for an ostrich by Sanji. He is the leader of the Super Spot-Billed Duck Squad in Arabasta.

Past
Carue has been Vivi's friend since childhood. On a quest to save Arabasta Kingdom, Carue, along with Vivi and Igaram, infiltrated Boraque Works, a secret crime organization that has been manipulating the people of Arabasta Kingdom. Vivi and Igaram managed to learn the boss's identity, Crocodile, who in turn decided to take action against them.

Whiskey Peak Arc
Carue was first introduces assisting Miss Wednesday (Vivi), Mr. 9, Miss Monday, and Mr. 8 in their fight against Zoro. Carue had trouble following the simplest instructions from Miss Wednesday. Eventually Zoro defeated the Boraque Works agents. Mr. 5 and Miss Valentine arrived on the scene with orders to eliminate Vivi. Carue helped Vivi evade the two officer agents until Luffy and Zoro intervened and defeated them. After Vivi accidentally told the Straw Hats of the boss's identity and Igaram's decoy ship blew up, Carue quickly fled Whiskey Peak with Vivi and the pirates.

Little Garden Arc
Following the log pose, the Straw Hats arrived at Little Garden. After disembarking, Carue and Vivi went with Luffy exploring the island a met a giant named Dori. After Dori drank some alcohol that had been tainted with explosives, the giant hold Luffy responsible and Carue quickly left the scene. While running through the jungle, the duck unfortunately ran into Mr. 5 and Miss Valentine. The two officer agents forced Carue to cry for help, but the duck remained silent. They beat Carue up and draged him to Dori's home where Luffy, Usopp, and Vivi are present. After Mr. 5 and Miss Valentine abducted Vivi, Carue, Luffy, and Usopp set out to save her. They found four Boraque Works agents on Little Garden: Mr. 5, Miss Valentine, Mr. 3, and Miss Goldenweek. They also found Vivi, Zoro, and Nami stuck on Mr. 3's candle set and in the process of turning into wax figures. Carue and Usopp spend most of the battle running from Mr. 5 and Miss Valentine, but they also helped Luffy break free from Miss Goldenweek's Color Traps. After Usopp figured out how to free Vivi, Zoro, and Nami, he had Carue run around and wrap Mr. 3's candle set with a rope coated with oil. Luffy then lights up the rope with the fire atop of Mr. 3's head freeing the captives. Luffy and Carue went after Mr. 3 and Miss Goldenweek as they were fleeing the scene. After Luffy knocked out Mr. 3, Carue attacked Miss Goldenweek.

After Sanji acquired an eternal pose to Arabasta from the Unluckies, Carue, Vivi, and the Straw Hats set sail for the desert kingdom.

Drum Island Arc
During the journey to Arabasta, Nami suddenly became sick and the crew needed to find a doctor. They disembarked on Drum Island and Zoro and Carue stayed behind to watch the ship. Zoro took a swim in the cold river to train himself. Carue, fearing that Zoro would freeze in the river, decided to jump after him but end up getting frozen in the river himself. After the crew recruited Chopper and returned to the ship, they found the frozen Carue and defrosted him.

Arabasta Arc
On their way to Arabasta, the Straw Hats were short on food. Luffy and Usopp decided to use Carue as bait to catch fish much to Vivi's dismay. After passing through a hot spot, Carue caught Mr. 2 Bon Kurei. After Bon Kurei is picked up by his own ship and crew and leave, the Straw Hats disembark on Arabasta. Vivi send Carue with a message to Alubarna to warn the King. Carue reached the palace and successfully delivered the message.

As Vivi and the Straw Hats (minus Luffy) make their way to Alubarna, Carue and the Spot Billed Duck Squad came to their aid and traveled to the capital. Once they reach the capital, the Straw Hats lured the Boraque Works officer agents away from Vivi. Vivi tried to stop the rebel army, but a dust cloud caused by a Baroque Works agent under cover in the royal army prevents the Rebel Army from seeing her. Carue covered Vivi preventing her from getting trampled down by the rebel army. When Mr. 2 arrived attempting to finish off Vivi, Carue ran off with her climbing the steep walls of Alubarna but still is pursued by Mr. 2. However, he gets delayed by Sanji, who buys Vivi time to get to the palace. On their way to the palace Carue was shot by a stray bullet. The Spot Billed Duck Squad took Carue to safety while Vivi head for the castle.

After Crocodile's defeat and the rebellion came to an end, Carue rest and recover in the castle with the Straw Hats.

Merchandise
He featured alongside Chopper in the One Piece Desert Kingdom Mascot Keychain/Cellphone Strap collection.

Translation and Dub Issues
His name comes from the Japanese word "karugamo," which means "spot-billed duck."

In the 4Kids dub, his name is pronounced as "Kuh-roo", but in the FUNimation dub, it's pronounced "KAH-rue".

Trivia

 * In the 4th Japanese Fan Poll, Carue is ranked the 53rd most popular character in One Piece.
 * Despite his long absence from the series and his separation from ties to the Straw Hat crew, Carue has been and still is being featured on the cover page of One Piece chapters several times along with Vivi.