The Caribbean reef shark (Carcharhinus perezi) is a requiem shark species found in the tropical waters of the western Atlantic Ocean, ranging from Florida to Brazil. It is the most common reef shark encountered in the Caribbean Sea. This sturdy shark is abundant in the Caribbean, and because of its average features, is often confused with other requiem sharks. As one of the largest apex predators in its ecosystem, understanding its diet is crucial to comprehending the dynamics of the coral reef communities it inhabits.
Physical Characteristics and Habitat
The Caribbean reef shark has a heavy-bodied, streamlined shape, making it difficult to distinguish from other large requiem shark species like the dusky shark (C. obscurus) and the silky shark (C. falciformis). They usually measure 2-2.5 m (6.6-8.2 ft) long; the maximum recorded length is 3 m (9.8 ft) and the maximum reported weight is 70 kg (150 lb). The coloration is dark gray or gray-brown above and white or white-yellow below, with an inconspicuous white band on the flanks. The snout of C. perezi is moderately short and broadly rounded. It has poorly developed, low anterior nasal flaps and relatively large circular eyes. Caribbean reef sharks also have moderately long gill slits with the third gill slit lying above the origin of the pectoral fin.
This shark’s common name, Caribbean reef shark, is quite suitable since the shark mainly inhabits coral reefs in the Caribbean and off South America. The Caribbean reef shark is the most common shark on or near coral reefs in the Caribbean. It is a tropical inshore, bottom-dwelling species of the continental and insular shelves. Although C. perezi mainly inhabits shallow waters, it has been recorded to reach depths to at least 98 feet (30 m). Caribbean reef sharks are commonly found close to drop-offs on the outer edges of coral reefs and also may lie motionless on the bottom of the ocean floor. They have been found ‘sleeping’ in caves and on the ocean floor, behavior that is still unexplained. They can be reliably observed resting in caves in Florida.
Dietary Preferences
Like many sharks, the Caribbean reef shark mainly eats bony fishes. Caribbean reef sharks are typical reef predators, mostly found on coral and rocky reefs in the Caribbean and Gulf of Mexico, but also down to southern Brazil. Caribbean reef sharks primarily consume reef fish, along with cephalopods (e.g. squid) and crustaceans (e.g. crabs). Larger individuals will also eat other elasmobranchs, including the yellow stingray and eagle rays.
The shark uses six keen senses to locate its prey: olfactory, visual, tactile (including water vibration sensitivity through a lateralis canal system), auditory, gustatory, and electric reception.
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Apex Predator Role
Usually growing 6.5 to 10 feet long, these are the apex predator of their food web. Adult reef sharks are often the apex predator wherever they live. Juvenile Caribbean reef sharks are preyed upon by larger sharks such as the tiger shark (Galeocerdo cuvier) and the bull shark (C. leucas).
Hunting Behavior
Caribbean reef sharks are more active at night, with no evidence of seasonal changes in activity or migration.
Threats to Humans
The Caribbean reef shark infrequently attacks humans. In general, a shark attack on a human is behaviorally similar to an attack upon natural prey. A human is more susceptible to being attacked if the shark is cornered and feels that there is no escape route. Another danger posed to humans by the Caribbean reef shark involves the accumulation of toxins in the flesh of the shark. Since sharks are apex marine predators, they may contain toxic levels of mercury and other heavy metals due to bioaccumulation (increasing concentrations at higher levels in the food web).
Reproduction and Life Cycle
Like other requiem sharks, it is viviparous with females giving birth to 4-6 young every other year. The Caribbean reef shark is a viviparous species, meaning its developing embryos are nourished via a placental connection. The litters average four to six pups. Although this shark’s reproduction has not been studied in the northern hemisphere, but to the south, parturition occurs during the Amazon summer of November to December. Pregnant females are often found to have biting scars from males on the sides of their bodies, due to the aggressive behaviors of males during mating. Gestation is believed to take approximately one year. A pregnant female with biting scars and wounds on the sides of her body, taken off the coast of north-northeastern Brazil, carried four near-term embryos. One was a 27.5 in. (700 mm) long male and three were females measuring 27.0 in. (685 mm), 27.4 in. (697 mm), and 27.7 in. (704 mm) in length. Because she was carrying near-term embryos, it is postulated that this area may be a pupping ground. Although such captures have shed light on the topic, relatively little is known about the reproduction of the Caribbean reef shark. Much information has been obtained from a pregnant female carrying four near-term embryos off the coast of northeastern Brazil. This female had scars and wounds on her side. The lifespan is around 15 years.
Conservation Status and Threats
The International Union for Conservation of Nature (IUCN) has assessed the Caribbean reef shark as Endangered; 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. Commercial fishing for this species is prohibited in United States waters. 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. The Caribbean reef shark is currently listed as “Near Threatened” on the World Conservation Union (IUCN) Redlist.
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Throughout their range, Caribbean reef sharks are a valuable resource to fisheries and ecotourism operations. The Caribbean reef shark is the most common shark landed in Colombia (accounting for 39% of the longline catch by occurrence), where it is utilized for its fins, oil and jaws (sold for ornamental purposes). In Belize, this species is mainly caught as bycatch on hook-and-line intended for groupers and snappers; the fins are sold to the lucrative Asian market and the meat sold in Belize, Mexico, and Guatemala to make "panades", a tortilla-like confection.
Ecotourism and Shark Feeding
A profitable ecotourism industry has arisen around this species involving organized "shark feeds", in which groups of reef sharks are attracted to divers using bait. This practice has drawn controversy, as opponents argue that the sharks may learn to associate humans with food, increasing the chances of a shark attack, and that the removal of reef fishes for bait may damage the local ecosystem. Conversely, proponents maintain that shark feeds contribute to conservation by incentivizing the protection of sharks and educating people about them.
Taxonomic Information
The Caribbean reef shark (Carcharhinus perezi) is a species of requiem shark, belonging to the family Carcharhinidae. The Caribbean reef shark was originally described as Platypodon perezi by Felipe Poey in 1876, in the scientific journal Anales de la Sociedad Española de Historia Natural. The type specimens were six individuals caught off the coast of Cuba. Bigelow and Schroeder later described the same species as Carcharhinus springeri in 1944 and the reef shark appears in much literature under this scientific name. The genus name Carcharhinus is derived from the Greek “karcharos” = sharpen and “rhinos” = nose. The currently accepted valid name is C.
Distinguishing Features
The Caribbean reef shark has an interdorsal ridge from the rear of the first dorsal fin to the front of the second dorsal fin. The second dorsal fin has a very short free rear tip. The upper teeth of the Caribbean reef shark have narrow cusps with serrated edges and broad bases. The front two to four teeth on each side of the jaw are erect and the others are increasingly oblique. The dermal denticles of the Caribbean reef shark have a large number of marginal teeth and ridges. They are closely and regularly overlapping.
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