Still others build tunnels in the rocks or sand, hide under larger rocks or blend in with whatever is in the area. They are all looking for a meal and trying to avoid becoming one. In shallow water you'll find a dazzling array of life under the rocks. I do not advocate disrupting the coral reef, so carefully turn over and replace rocks the way you found them. Concentrate on having a low impact on the fragile shallow reefs.
Animals hide under rocks for protection.
If you notice other fish waiting around for you to turn things over, don't do it. You will be causing the unnatural death of some small creature. In sea grass or algae you will find snails nudebranchs and perhaps see a shelless animal called the sea hare feeding along the reef. Some can be coaxed out from it's hiding place momentarily, while others might even tolerate your gently handling of them. Remember to help them back where they belong.