In the movie, when Bernard and Miss Bianca go to find Orville to get a flight to Australia to rescue the kidnapped boy Cody, they find out that Orville no longer runs the Albatross Airlines. However, his brother Wilbur does. Bernard and Bianca find Wilbur dancing to some music that Bernard has to stop in order to get Wilbur's attention. When Wilbur meets Miss Bianca he tells her that Orville told him all about her. Bernard asks Wilbur to give them a flight tonight but Wilbur refuses because of the snow storm outside but when they tell him about the kidnapped boy, Cody, Wilbur suddenly feels bad and gives the mice a flight to Australia. His takeoff is so fast and clumsy it causes a car accident below on the streets. On the way they make connections with an airliner plane also en route to Australia and fall asleep in the plane's cargo holder. When the plane gets to Australia, Wilbur flies the mice out and into a little airport where a kangaroo mouse named Jake works.
When Wilbur radios into Jake about landing, Jake tells Wilbur to turn around because the runway isn't big enough for a bird his size. But Wilbur refuses and lands on the runway anyway. When Wilbur lands, Jake helps Bernard and Bianca off the bird. Wilbur has back pain from landing on the runway and Jake helps get Wilbur get to the hospital, where Bernard, Bianca and Jake tell Wilbur they'll come back for him as soon as they find Cody and leave. At the hospital the doctor has Wilbur undergo several operations, including shooting a rifle loaded with tranquilizers at him. The next morning the nurse mice put Wilbur's head in a vice and are preparing to use a chainsaw, which they refer to as the epidermal tissue disruptor, on him, causing Wilbur to panic. He tries to escape but the Nurse Mice pull him back inside and he lies flat on his back on top of the doctor. His back feels better and he turns bad. He exits, flying off to find Bernard, Bianca, and Jake. While flying Wilbur notices some female birds and asks them if they've seen any mice wandering down there, but the birds ignore him and fly off. Soon, Wilbur arrives where Bernard is hiding Marahute's eggs. Bernard orders him to sit on Marahute's eggs to keep them warm while he goes to rescue Cody, Bianca, Jake, and Marahute from the evil poacher, Percival C. McLeach.
At the end, Wilbur is seen still sitting on the eggs and calling for Bernard and Bianca, but just as he's about to fly away, the eggs hatch and Wilbur finds out that one of Marahute's babies is cute and when he was cooing, there was a sound of the crack, causing Wilbur to scream in pain as the credits to the movie roll.
Since The Rescuers Down Under was the only sequel in the series, it's unknown what happens to Wilbur after the babies hatch at the end of the film. He might become the new mate of Marahute since she lost her first mate, but this is doubtful, since Wilbur and his brother Orville are both based on the Wright Brothers, and neither brother in real life ever got married or had kids. Hopefully, Bernard and Bianca, who were seen at the end of the movie riding Marahute, eventually remembered about Wilbur and returned to him so he could take them back to New York City, but the rest remains unknown.
Storyboards for an unused extension to the film's ending (seen in the book Paper Dreams: The Art & Artists of Disney Storyboards), in which Bernard and Bianca ride off on Wilbur after their wedding, suggest that they evidently did return to him.
Like his brother, Orville, Wilbur is named after Wilbur Wright of the Wright brothers.
Although Wilbur and Orville look alike (since they're brothers), you can tell the difference between the looks of the two albatross brothers by the scarf color; Wilbur's scarf is aqua-colored, while Orville's scarf is lavender-colored.