Nassau Grouper Displaying Territorial Behavior!!

In the beautiful video below, filmed by Frans De Backer, you will see several Nassau Grouper engaging in some pretty interesting behaviors.  Nassau spend most of their lives living in one particular area of the reef and they don’t like to share their territory with other Nassau Groupers.  Pay close attention to their coloration!  Do you think their behavior with be different during the spawning event?  If so, how?

  http://vimeo.com/63104193