"Di, we will always love you. And we will miss you so much. But I know that you will be happy. For now, you truly are in the eternal 'Cat Haven,'" Paul Hanson said in the statement.
The sanctuary will remain closed to the public today.
Cous Cous was raised at the preserve from 8 weeks old, and even made an appearance on "The Ellen DeGeneres Show" when he was a cub.
Cat Haven was founded in 1993 and is run by Project Survival, a privately funded education and conservation organization.
The 100-acre facility is home to a variety of wild cats -- including tigers, leopards and other threatened and endangered species that are kept for limited breeding and use in educational programs, according to Cat Haven's website.
Officials said the park has had a good history, and had an active permit to operate.
Cat Haven also runs an outreach program, and its "cat ambassadors" may sometimes be taken off-site to make appearances as part of that program, according to the website.
The preserve is run by a core staff supported by volunteers.
Editor's Note: A previous version of this story incorrectly stated that an internship is required by the Association of Zoos and Aquariums in order to work at an AZA-accredited zoo or aquarium. No such requirement is in place, according to AZA Senior Vice President Steve Feldman.
ABC News' Larry Dechant and Suzan Clarke contributed to this report.