From the Ringling Brothers website:
17. Can I bring my camera or video camera to the show?
Ringling Bros. policy is that no video cameras of any kind are allowed in the arena; however still cameras are permitted providing they are non-professional type cameras, and the photos are intended for personal use only. Since the definition of non-professional cameras and the use of digital cameras varies from arena to arena; please contact your local arena to verify their policy.
http://www.ringling.com/general/faq.aspx#17