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Like all sharks, the blacktip reef shark has exceptional sensory systems. From there keen sense of smell to having the ability to see in low light condition, these adaptation have made them prestige at tracking down there prey. Sharks also have an additional sixth sense where they can sense electromagnetic fields in the water. The ampullae of Lorenzini, located in the snout region, enable a shark to detect its prey without physically seeing it.
The Caribbean Reef Shark also finds its food in the reefs such as bony fishes, large crustaceans and cephalopods. This shark is also known to feed on yellow sting-rays and eagle rays quite frequently. A unique feature of these predators is that they are capable of reverting or purging their own stomachs. This helps purge the parasites, mucus or any other objects on the stomach lining.

These sharks prefer the shoreline from Florida to Brazil. This is where it gets the common name from. The tropical parts of the western Atlantic Ocean is home to this variety of sharks. Normally found on the outer edges of reefs, the Caribbean Reef Shark prefers to live in coral reefs and its shallow waters as well as continental shelves and insular shelves. These sharks are found quite commonly at a depth of about 100 feet (30 meters) and are known to dive to incredible depths of around 1250 feet (380 meters).
Reproduction is viviparous; once the developing embryos exhaust their supply of yolk, the yolk sac develops into a placental connection through which they receive nourishment from their mother. Mating is apparently an aggressive affair, as females are often found with biting scars and wounds on their sides.[4] At the Fernando de Noronha Archipelago and Atol das Rocas off Brazil, parturition takes place at the end of the dry season from February to April, while at other locations in the Southern Hemisphere, females give birth during the Amazon summer in November and December.[4][12] The average litter size is four to six, with a gestation period of one year. Females become pregnant every other year.[8] The newborns measure no more than 74 cm (29 in) long; males mature sexually at 1.5–1.7 m (59–67 in) long and females at 2–3 m (79–118 in).[4]
Blowhole Cliffed coast Coastal biogeomorphology Coastal erosion Concordant coastline Current Cuspate foreland Discordant coastline Emergent coastline Feeder bluff Fetch Flat coast Graded shoreline Headlands and bays Ingression coast Large-scale coastal behaviour Longshore drift Marine regression Marine transgression Raised shoreline Rip current Rocky shore Sea cave Sea foam Shoal Steep coast Submergent coastline Surf break Surf zone Surge channel Swash Undertow Volcanic arc Wave-cut platform Wave shoaling Wind wave Wrack zone
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]
Are there so few reef sharks because of human activities such as fishing and finning, or were there never very many to start with? To answer this question, a team of marine biologists (which did not include Friedlander) decided to count reef sharks at coral reefs close and far to human settlements to better understand how humans impact their populations.
They are also found in mangrove areas, moving in and out with the tide and even in fresh water near the sea. They occur singly or in small groups. Adults often aggregate in reef channels at low tide. This is one of the three most common reef sharks in the Indo-Pacific, the two others are the grey reef shark, Carcharhinus amblyrhynchos and whitetip reef shark, Triaenodon obesus.
Along with the blacktip reef shark (C. melanopterus) and the whitetip reef shark (Triaenodon obesus), the grey reef shark is one of the three most common sharks inhabiting Indo-Pacific reefs. They actively expel most other shark species from favored habitats, even species larger in size.[3] In areas where this species co-exists with the blacktip reef shark, the latter species occupies the shallow flats, while the former stays in deeper water.[4] Areas with a high abundance of grey reef sharks tend to contain few sandbar sharks (C. plumbeus), and vice versa; this may be due to their similar diets causing competitive exclusion.[11]
These sharks prefer the shoreline from Florida to Brazil. This is where it gets the common name from. The tropical parts of the western Atlantic Ocean is home to this variety of sharks. Normally found on the outer edges of reefs, the Caribbean Reef Shark prefers to live in coral reefs and its shallow waters as well as continental shelves and insular shelves. These sharks are found quite commonly at a depth of about 100 feet (30 meters) and are known to dive to incredible depths of around 1250 feet (380 meters).
The snout is rather short, broad, and rounded, without prominent flaps of skin beside the nostrils. The eyes are large and circular, with nictitating membranes (protective third eyelids). There are 11–13 tooth rows in either half of both jaws. The teeth have broad bases, serrated edges, and narrow cusps; the front 2–4 teeth on each side are erect and the others increasingly oblique. The five pairs of gill slits are moderately long, with the third gill slit over the origin of the pectoral fins.[4] The first dorsal fin is high and falcate (sickle-shaped). There is a low interdorsal ridge running behind it to the second dorsal fin, which is relatively large with a short free rear tip. The origin of the first dorsal fin lies over or slightly forward of the free rear tips of the pectoral fins, and that of the second dorsal fin lies over or slightly forward of the anal fin. The pectoral fins are long and narrow, tapering to a point.[2] The dermal denticles are closely spaced and overlapping, each with five (sometimes seven in large individuals) horizontal low ridges leading to marginal teeth.[4]
Off Enewetak, grey reef sharks exhibit different social behaviors on different parts of the reef. Sharks tend to be solitary on shallower reefs and pinnacles. Near reef drop-offs, loose aggregations of five to 20 sharks form in the morning and grow in number throughout the day before dispersing at night. In level areas, sharks form polarized schools (all swimming in the same direction) of around 30 individuals near the sea bottom, arranging themselves parallel to each other or slowly swimming in circles. Most individuals within polarized schools are females, and the formation of these schools has been theorized to relate to mating or pupping.[25][26]
Caribbean reef sharks are sometimes seen resting motionless on the sea floor or inside caves; it is the first active shark species in which such a behavior was reported. In 1975, Eugenie Clark investigated the famed "sleeping sharks" inside the caves at Isla Mujeres off the Yucatan Peninsula, and determined that the sharks were not actually asleep as their eyes would follow divers. Clark speculated that freshwater upwellings inside the caves might loosen parasites on the sharks and produce an enjoyable "narcotic" effect.[8] If threatened, Caribbean reef sharks sometimes perform a threat display, in which they swim in a short, jerky fashion with frequent changes in direction and repeated, brief (1–1.2 second duration) drops of the pectoral fins. This display is less pronounced than the better-known display of the grey reef shark (C. amblyrhynchos).[8][9]

Blacktip reef sharks are viviparous with a yolk-sac placenta, with a gestation period about 10 months and litter size of 2-4 pups. Size at birth ranges from 33-52 cm. Males mature at about eight years of age and 95-105 cm in length; females mature at about 9 years old and a length of 93-110 cm. Courtship features the one or more males following closely behind a female. Reproductive behavior includes distinct pairing with embrace where the male grasps the female’s pectoral fin between his teeth and mates belly to belly. There is one breeding season in the central and western Pacific, but two seasons in the Indian Ocean. Females rest for 8-14 month between pregnancies to rebuild their energy stores. Blacktip reef sharks are preyed upon by other sharks and large groupers. The is a socially complex species that performs a variety of group behaviors.


The International Union for Conservation of Nature (IUCN) has assessed the Caribbean reef shark as Near Threatened; its population has declined off Belize and Cuba from overfishing and exploitation continues in other regions. They are also threatened by the degradation and destruction of their coral reef habitat.[1] Commercial fishing for this species is prohibited in United States waters.[4] They are protected in the Bahamas due to their significance to ecotourism, as well as in a number of Marine Protected Areas (MPAs) off Brazil and elsewhere. However, enforcement against illegal fishing is lacking in some of these reserves, and many areas in which this species is abundant are not protected.[1]
Despite its abundance in certain areas, the Caribbean reef shark is one of the least-studied large requiem sharks. They are believed to play a major role in shaping Caribbean reef communities. These sharks are more active at night, with no evidence of seasonal changes in activity or migration. Juveniles tend to remain in a localized area throughout the year, while adults range over a wider area.[7]
Grey reef sharks are often curious about divers when they first enter the water and may approach quite closely, though they lose interest on repeat dives.[4] They can become dangerous in the presence of food, and tend to be more aggressive if encountered in open water rather than on the reef.[13] There have been several known attacks on spearfishers, possibly by mistake, when the shark struck at the speared fish close to the diver. This species will also attack if pursued or cornered, and divers should immediately retreat (slowly and always facing the shark) if it begins to perform a threat display.[4] Photographing the display should not be attempted, as the flash from a camera is known to have incited at least one attack.[3] Although of modest size, they are capable of inflicting significant damage: during one study of the threat display, a grey reef shark attacked the researchers' submersible multiple times, leaving tooth marks in the plastic windows and biting off one of the propellers. The shark consistently launched its attacks from a distance of 6 m (20 ft), which it was able to cover in a third of a second.[14] As of 2008, the International Shark Attack File listed seven unprovoked and six provoked attacks (none of them fatal) attributable to this species.[29]
But another potential cause is that these sharks are skittish around people. So when too many people move into the area, the reef sharks flee to other coral reefs. Indeed, the researchers found far more sharks at small, isolated reefs than they expected. But this in itself is a danger to the reef sharks. With so many sharks concentrated in a small area, “if you really wanted to, you could fish out a few hundred sharks very easily,” said Friedlander.
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The "hunch" threat display of the grey reef shark is the most pronounced and well-known agonistic display (a display directed towards competitors or threats) of any shark. Investigations of this behavior have been focused on the reaction of sharks to approaching divers, some of which have culminated in attacks. The display consists of the shark raising its snout, dropping its pectoral fins, arching its back, and curving its body laterally. While holding this posture, the shark swims with a stiff, exaggerated side-to-side motion, sometimes combined with rolls or figure-8 loops. The intensity of the display increases if the shark is more closely approached or if obstacles are blocking its escape routes, such as landmarks or other sharks. If the diver persists, the shark will either retreat or launch a rapid open-mouthed attack, slashing with its upper teeth.[3]
But another potential cause is that these sharks are skittish around people. So when too many people move into the area, the reef sharks flee to other coral reefs. Indeed, the researchers found far more sharks at small, isolated reefs than they expected. But this in itself is a danger to the reef sharks. With so many sharks concentrated in a small area, “if you really wanted to, you could fish out a few hundred sharks very easily,” said Friedlander.

The Caribbean reef shark feeds on a wide variety of reef-dwelling bony fishes and cephalopods, as well as some elasmobranchs such as eagle rays (Aetobatus narinari) and yellow stingrays (Urobatis jamaicensis).[1] It is attracted to low-frequency sounds, which are indicative of struggling fish.[4] In one observation of a 2 m (6.6 ft) long male Caribbean reef shark hunting a yellowtail snapper (Lutjanus crysurus), the shark languidly circled and made several seemingly "half-hearted" turns towards its prey, before suddenly accelerating and swinging its head sideways to capture the snapper at the corner of its jaws.[8] Young sharks feed on small fishes, shrimps, and crabs.[8] Caribbean reef sharks are capable of everting their stomachs, which likely serves to cleanse indigestible particles, parasites, and mucus from the stomach lining.[11]
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