Most observed displays by grey reef sharks have been in response to a diver (or submersible) approaching and following it from a few meters behind and above. They also perform the display towards moray eels, and in one instance towards a much larger great hammerhead (which subsequently withdrew). However, they have never been seen performing threat displays towards each other. This suggests the display is primarily a response to potential threats (i.e. predators) rather than competitors. As grey reef sharks are not territorial, they are speculated to be defending a critical volume of "personal space" around themselves. Compared to sharks from French Polynesia or Micronesia, grey reef sharks from the Indian Ocean and western Pacific are not as aggressive and less given to displaying.[3]
The Caribbean reef shark (Carcharhinus perezi) is a species of requiem shark, belonging to the family Carcharhinidae. It is found in the tropical waters of the western Atlantic Ocean from Florida to Brazil, and is the most commonly encountered reef shark in the Caribbean Sea. With a robust, streamlined body typical of the requiem sharks, this species is difficult to tell apart from other large members of its family such as the dusky shark (C. obscurus) and the silky shark (C. falciformis). Distinguishing characteristics include dusky-colored fins without prominent markings, a short free rear tip on the second dorsal fin, and tooth shape and number.
In older literature, the scientific name of this species was often given as C. menisorrah.[5] The blacktail reef shark (C. wheeleri), native to the western Indian Ocean, is now regarded as the same species as the grey reef shark by most authors. It was originally distinguished from the grey reef shark by a white tip on the first dorsal fin, a shorter snout, and one fewer upper tooth row on each side.[6] Based on morphological characters, vertebral counts, and tooth shapes, Garrick (1982) concluded the grey reef shark is most closely related to the silvertip shark (C. albimarginatus).[7] This interpretation was supported by a 1992 allozyme phylogenetic analysis by Lavery.[8]
In California, Reef Check helps ensure the long-term sustainability and health of the nearshore rocky reefs and kelp forests. Reef Check California volunteers are divers, fishermen, kayakers, surfers, boaters, and a wide range of Californians who take a proactive role in making sure that our nearshore ecosystems are healthy and well managed. We monitor rocky reefs inside and outside of California's marine protected areas (MPAs). We work with marine managers, researchers and the public to provide the scientific data needed to make informed, science-based decisions for the sustainable management and conservation of California's ocean environment. We would love your support, volunteer today!

Dutch ichthyologist Pieter Bleeker first described the grey reef shark in 1856 as Carcharias (Prionodon) amblyrhynchos, in the scientific journal Natuurkundig Tijdschrift voor Nederlandsch-Indië. Later authors moved this species to the genus Carcharhinus. The type specimen was a 1.5 metres (4.9 ft)-long female from the Java Sea.[4] Other common names used for this shark around the world include black-vee whaler, bronze whaler, Fowler's whaler shark, graceful shark, graceful whaler shark, grey shark, grey whaler shark, longnose blacktail shark, school shark, and shortnose blacktail shark. Some of these names are also applied to other species.[2]

There is a variety of biotic reef types, including oyster reefs and sponge reefs, but the most massive and widely distributed are tropical coral reefs. Although corals are major contributors to the framework and bulk material comprising a coral reef; the organisms most responsible for reef growth against the constant assault from ocean waves are calcareous algae, especially, although not entirely, coralline algae.
×