The Caribbean reef shark occurs throughout the tropical western Atlantic Ocean, from North Carolina in the north to Brazil in the south, including Bermuda, the northern Gulf of Mexico, and the Caribbean Sea. However, it is extremely rare north of the Florida Keys. It prefers shallow waters on or around coral reefs, and is commonly found near the drop-offs at the reefs' outer edges.[4] This shark is most common in water shallower than 30 m (98 ft), but has been known to dive to 378 m (1,240 ft).[1]
With more than 60 years of experience in manufacturing and fabricating flexible plastic laminates, Reef Industries has the expertise in helping customers tackle the challenges they face when needing solutions to safeguard and prolong the service life of their investments. From protecting equipment during outdoor storage to ensuring buried utilities are protected from accidental dig-ins, Reef Industries provides customers with dependable and proven high-quality materials for long-term performance.

Tax-deductible donations made to Tetiaroa Society help fund critical conservation efforts, scientific research being conducted at our Ecostation, and education programs for the local schools. Your contribution also helps us advance what we are doing on Tetiaroa as a model for island/earth sustainability. We deeply appreciate your generosity and look forward to sharing our progress with you.


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]
Grey reef sharks are prey for larger sharks, such as the silvertip shark.[9] At Rangiroa Atoll in French Polynesia, great hammerheads (Sphyrna mokarran) feed opportunistically on grey reef sharks that are exhausted from pursuing mates.[15] Known parasites of this species include the nematode Huffmanela lata and several copepod species that attach to the sharks' skin,[16][17] and juvenile stages of the isopods Gnathia trimaculata and G. grandilaris that attach to the gill filaments and septa (the dividers between each gill).[18][19]
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]
Socially, they are mostly loners unless living in a threatening ecosystem. These are the first and the only species of sharks that are known to “sleep” on the ocean floor or within reef caves. It is believed that these sharks are not actually sleeping but merely resting. These sharks have actually been given the nickname “sleeping sharks” because of their habit of lying motionless at the sea bottom. This is a somewhat unusual and unique behavior of these sharks.
Founded in 1996, the Reef Check Foundation exists to help preserve the oceans and reefs which are critical to our survival, yet are being destroyed. With headquarters in Los Angeles and volunteer teams in more than 90 countries and territories, Reef Check works to protect tropical coral reefs and California rocky reefs through education, research and conservation.
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]
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.
The grey reef shark has a streamlined, moderately stout body with a long, blunt snout and large, round eyes. The upper and lower jaws each have 13 or 14 teeth (usually 14 in the upper and 13 in the lower). The upper teeth are triangular with slanted cusps, while the bottom teeth have narrower, erect cusps. The tooth serrations are larger in the upper jaw than in the lower. The first dorsal fin is medium-sized, and there is no ridge running between it and the second dorsal fin. The pectoral fins are narrow and falcate (sickle-shaped).[4]
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 coloration is grey above, sometimes with a bronze sheen, and white below. The entire rear margin of the caudal fin has a distinctive, broad, black band. There are dusky to black tips on the pectoral, pelvic, second dorsal, and anal fins.[9] Individuals from the western Indian Ocean have a narrow, white margin at the tip of the first dorsal fin; this trait is usually absent from Pacific populations.[5] Grey reef sharks that spend time in shallow water eventually darken in color, due to tanning.[10] Most grey reef sharks are less than 1.9 m (6.2 ft) long.[4] The maximum reported length is 2.6 m (8.5 ft) and the maximum reported weight is 33.7 kg (74 lb).[9]


Despite sharks being portrayed as notorious aggressive animals, very few incidents have involved blacktip reef sharks, none being fatal. Still the importance of an apex predator is vital to a balanced and healthy ecosystem. Unfortunately, this species is very susceptible to reef gill netting. And sharks all around continue to be threatened by fishing pressure resulting in a decrease in many shark populations.
There is little evidence of territoriality in the grey reef shark; individuals will tolerate others of their species entering and feeding within their home ranges.[27] Off Hawaii, individuals may stay around the same part of the reef for up to three years,[28] while at Rangiroa, they regularly shift their locations by up to 15 km (9.3 mi).[27] Individual grey reef sharks at Enewetak become highly aggressive at specific locations, suggesting they may exhibit dominant behavior over other sharks in their home areas.[3]
Cyanobacteria do not have skeletons and individuals are microscopic. Cyanobacteria can encourage the precipitation or accumulation of calcium carbonate to produce distinct sediment bodies in composition that have relief on the seafloor. Cyanobacterial mounds were most abundant before the evolution of shelly macroscopic organisms, but they still exist today (stromatolites are microbial mounds with a laminated internal structure). Bryozoans and crinoids, common contributors to marine sediments during the Mississippian (for example), produced a very different kind of mound. Bryozoans are small and the skeletons of crinoids disintegrate. However, bryozoan and crinoid meadows can persist over time and produce compositionally distinct bodies of sediment with depositional relief.
×