LOS ANGELES (Reuters) - Anne Hathaway, Neil Patrick Harris and Rodrigo Santoro are negotiating to lend their voices to Rio, the next collaboration between Blue Sky Studios, Fox Animation and director Carlos Saldanha, all of whom are riding the $882 million global tsunami of Ice Age: Dawn of the Dinosaurs. Rio, which follows the adventures of a nerdy macaw who lights out from his small-town Minnesota cage for the exotic Summer Olympic city of Rio de Janeiro, is scheduled for an April 8, 2011, release. Like Dinosaurs, it will be filmed in 3D digital animation. Chris Jenkins (Surfs Up) and Bruce Anderson (Dr. Seuss Horton Hears a Who) are producing. Hathaway and Harris have done animation before. Hathaway voiced the lead role of Red in the Weinstein Co. release Hoodwinked in 2005, and Harris voiced a character in Sony Pictures Animations Cloudy With a Chance of Meatballs. Fox would not confirm casting. With the three Ice Age movies, Horton and Robots, Blue Sky and Fox have generated $2.4 billion in worldwide grosses since 2002. The Brazilian-born Saldanha, who has been developing Rio for years, has had a hand in all of them except Horton. Hathaway most recently starred in Bride Wars. She next appears in Valentines Day and as the White Queen in Tim Burtons Alice in Wonderland. Harris recently hosted the Emmys and continues to star on the CBS comedy How I Met Your Mother. He next stars in the CBS Films release Beastly, hitting theaters in July. Santoro has starred in Post Grad, Che, Redbelt and 300. He next appears in There Be Dragons, directed by Roland Joffe.