Hawaii: Strange Ring Shaped Clouds Reported

Strange cloud formation filmed and sent in by a reader, filmed on July 26th at approximately 12:30 PM Hawaii time.  It may gave been a contrail from a plane flying concentric circles but then again it may not?
Filmers Comments: 
Hey I filmed this very strange cloud formation out over the ocean on Oahu. Never seen anything like it. Can't find any information on it as well and the local new didn't