Caribbean reef shark  (Carcharhinus perezi)

Classified as Near Threatened on the IUCN Red List (1).

The most common shark in the Caribbean Sea, the Caribbean reef shark displays the characteristic shark form, with a long, powerful, stream-lined body, a large dorsal fin, and greyish upperparts, fading into a white underside (2) (3). Physically similar to a number of related species, the Caribbean reef shark is distinguished by a relatively short, broadly rounded snout, and a ridge running between the rather straight, first dorsal fin and the reduced, second dorsal fin (2). The eyes are large and conspicuous, and moderately long gill slits sit above tapered pectoral fins (2) (4). The elongated caudal fin is well developed, propelling the shark through the water in a powerful, yet graceful motion (2).

The Caribbean reef shark is found throughout the tropical waters of the West Atlantic and the Caribbean Sea, from the southeast coast of Florida, south to Brazil (1). 

Most abundant around the outer edges of coral reefs, the Caribbean reef shark inhabits shallow coastal waters, up to a depth of 30 metres. Juveniles are rarely found occupying the same habitat as adults, showing a preference for shallow lagoons and forereefs (1). The Caribbean reef shark is occasionally found in caves off the Mexican coast and the Brazilian archipelago of Fernando de Noronha (3).

An active, aggressive predator, the Caribbean reef shark preys upon bony fish, large crustaceans, and other elasmobranchs, dwelling on or near the ocean floor (1). Prey is located using acute eyesight, a keen sense of smell, and specialised organs around the head that detect electric vibrations, and subsequently captured in sharp, serrated teeth, after a sudden, sideways snap of the crushing jaw (2). Between hunting forays, the Caribbean reef shark may be observed lying motionless on the ocean floor, a behaviour leading to the species being given the nickname, the ‘sleeping shark’ (5). The Caribbean reef shark may itself fall prey to larger sharks, such as the bull shark (Carcharhinus leucas) and the tiger shark (Galeocerdo cuvier) (3). 

The Caribbean reef shark is viviparous, giving birth to four to six live young during the summer months, after a gestation period of around one year. During mating, the males are extremely aggressive, and pregnant females are often seen with large scars on the sides of the body from biting. Females may travel to nursery grounds to give birth, with possible sites off the coast of northeast Brazil (3). Juveniles prefer shallow waters that offer safety from predators, sheltering during the day and foraging at night (6).

A victim of intensive fishing in the 20^th century, the Caribbean reef shark has suffered significant declines. Often driven by the demand for shark fins in Southeast Asia, where they are considered a delicacy, dedicated shark fisheries operated throughout the Caribbean, before dramatic reductions in catches forced many to shutdown in the late 1990s. However, fishing pressures still persist, and the Caribbean reef shark is found in an alarming 39 percent of fishing catches on the San Andrés Archipelago, Colombia. But in common with most other sharks, the greatest threat to the Caribbean reef shark is accidental bycatch in longline and gillnet fisheries. It is also caught in hook and line grouper and snapper fisheries, and there is growing concern about the effect this is having on the population. The Caribbean reef shark is also sought after as trophies in sport fishing, and is also taken for its skin and oils, which are used to make leather and beauty products (1).

The Caribbean reef shark is protected in the United States, and shark fishing is prohibited in some Cuban waters,  resulting in a noticeable increase in sightings in parts of the species’ range (1). The Caribbean reef shark is also protected in a large number of Marine Protected Areas (MPAs), and an increased abundance within several MPAs has been observed (6) (7). However, MPAs are often highly fragmented, and no-take restrictions may be poorly enforced. Furthermore, there are no binding international treaties for the management of sharks, including the regulation or outlawing of finning (8). Fortunately, the Caribbean reef shark is still relatively abundant and widespread, and measures to protect coastal habitats and wildlife will ensure this majestic shark continues to grace our tropical oceans (1).

To find out more about the threats to sharks, see: 

• The Shark Trust:
  http://www.sharktrust.org/
 
• The Shark Research Institute: 
  http://www.sharks.org/
 
• Conservation International: 
  http://www.conservation.org/learn/biodiversity/species/profiles/sharks/Pages/threats.aspx