These images of Millie and Roy dancing are from an 8-second dance sequence on August 18, 2006. Barbaro, their colt, had made her first flight two days earlier. Note that each time Roy jumps, he apparently vocalizes.
For a discussion of dancing, click on the link above: "Why do cranes dance?"and also see Alaska Sandhill Crane Blog for June 18, 2009.
For dancing with colts, see the galleries: "Roy's tour jete" and "Dance training".