The Spotted Eagle Ray, (Aetobatus narinari), is a cartilagionus fish of the eagle ray family, Myliobatidae. As traditionally recognized, it is found globally in tropical regions, including the Atlantic, pacific and Indian Oceans. Spotted eagle rays are most commonly seen alone, but occasionally swim in groups. They are ovoviviparous, the female retaining the eggs then releasing the young as miniature versions of the parent. This ray can be identified by its dark dorsal surface covered in white spots or rings. Near the base of the ray’s relatively long tail, just behind the pelvic fins, are several venomous, barbed stingers. Spotted eagle rays commonly feed on small fish and crustaceans, and will sometimes dig with their snouts to look for food buried in the sand of the sea bed. aquila di mare maculata
The spotted eagle ray is hunted by a wide variety of sharks. However, in coral reefs it often happens to see the spotted eagle ray in more or less numerous schools swimming together with sharks and sharing the same stretch of sea. As you can see in the video we made in the Maldives. The rays are considered near threatened on the IUCN Red List. They are fished mainly in Southeast Asia and Africa, the most common market being in commercial trade and aquariums. They are protected in the Great Barrier Reef.
(extract from Wikipedia)
Over 4,000 species of fish inhabit coral reefs. The reasons for this diversity remain unclear. Hypotheses include the “lottery”, in which the first (lucky winner) recruit to a territory is typically able to defend it against latecomers, “competition”, in which adults compete for territory, and less-competitive species must be able to survive in poorer habitat, and “predation”, in which population size is a function of postsettlement piscivore mortality. Healthy reefs can produce up to 35 tons of fish per square kilometer each year, but damaged reefs produce much less.