Blackeye Goby

This Blackeye goby was sitting on a shelf at Blue Caverns on Catalina.  His deep-yellow coloration is unusual; the more common colorations being beige, beige-and-white, or ivory.  Like some other blackeye gobies I've seen, he had his mouth open: was he singing?  Blackeye gobies certainly live in loose groups and communicate quite a bit: mostly by body language rather than song, however!