He is a tall, slender bird who one day lands on the telephone wire Bully and his flock of birds (including Chipper, Snob, and Neurotic) were already perching on. Bully and his flock first noticed the Big Bird when he honked and when they first saw him he waved hello and expanded his crest. After they notice how different the Big Bird was, the smaller birds immediately start making fun of him and mockingly imitated his appearance and voice until he honked again. The birds then moved farther across the wire from the Big Bird and began whispering to each other about him. The Big Bird tried to reach over to hear what they were saying, but almost fell off the wire, so he flew over to them. He then calls to the smaller birds as he lands between them; his weight caused the wire to sag and bend downwards, causing the smaller birds to slide toward him and therefore making them very annoyed. They chirped at him to move off, but he misinterpreted it as singing, causing him to "sing" along with them. Bully then pecks Big Bird near the leg, causing him to fall under the wire, but he still manages to hold on. Bully, still trying to get rid of him immediately, pecks at one of his toes, causing it to let go. He and the Bird next to him got an idea and started pecking at the rest of Big Bird's toes causing him to lose grip one by one. Neurotic notices this and has all of the smaller birds chant together at this. Big Bird notices this, and, without knowing why they're chanting for, joined them and hung down more. When Neurotic realized that there was only one of Big Bird's toes still grabbing onto the wire, which was dangerously close to the ground, he warns the other chanting birds and they immediately tries to tell Bully and the other bird to stop, but by the time they do, Big Bird has let go of the wire and causes it to bounce back up, knocking all of the smaller birds upwards with their feathers in the places the birds once were. Big Bird on the other had, was safely on the ground (though upside down, but he flipped himself back up again). He noticed the feathers floating down and blew several of them when Bully landed without any feathers, which Big Bird noticed and laughed at while offering Bully a leaf to cover himself up with (which he immediately took). When the other smaller birds also dropped with a few to none feathers on them. Big Bird laughed even harder as they ran into the bushes behind him out of embarrassment.
The Big Bird appears to resemble either a shoebill or a hamerkop (both tall, stork-like birds native to eastern Africa whose beaks resemble a wooden clog and a hammer, respectively).
Big Bird is also the name of a Jim Henson character associated with Sesame Street. However, the Sesame Street characters, unlike the Muppets, have no connection to Disney, although he appeared in the 1978 special, The Wonderful World of Disney and appeared with Mickey and Donald in the Little Golden Books back cover.