It is so exciting to see a grouper congregation of great size and great numbers below a rock or filling a canyon. The reason for this activity, that we are lucky to see occasionally, is a mystery to me. In this occasion there were not only groupers, but also a barred pargo and a green moray looking for space below this rock ledge (the green moray is not visible). There were more than 30 groupers in what we (my family and I) call a “cabrilla hole”, and that is only what is visible in my video. There were more fish way underneath the rock.