Great Ape Trust of Iowa is home to six orangutans. Azy, an adult male, arrived in the fall of 2004 from Smithsonian's National Zoological Park in Washington, DC.  He and Dr. Robert Shumaker have been research partners for nearly 25 years. Knobi, an adult female, came to Great Ape Trust in early 2005 from Henry Doorly Zoo in Omaha while Allie, an adolescent female, arrived from the Denver Zoo in late 2005.

In 2008, Great Ape Trust’s orangutan population increased to six with the arrival of three orangutans from the Los Angeles area: Rocky, a male juvenile, was the most visible orangutan in entertainment before his arrival to Great Ape Trust in July 2008. Also retired from entertainment were adult females Katy, Rocky’s biological mother, and Popi, who starred opposite Clint Eastwood in the 1980 blockbuster movie Any Which You Can. In 2008, Great Ape Trust also retired five other orangutans from the entertainment industry. Those apes are currently being cared for in California.