I didn't know Jacks..

....did this. While finishing up a transect the other day, I was coming to the top of a wall on the reef. A large bar jack swam right in front of me and pushed itself into some soft coral. It shimmied its way in like a lion in the grass. I thought, "Hmm, I haven't seen that before. Perhaps, it is hiding from me." Then it burst from the plumes and shot into a large group of brown chromis (picture not included). Hundreds of them scattered in every direction for about 2 seconds and then everything was back to normal.
Maybe soon I'll have a complete post with all of the pictures!