Carcharhinus limbatus
Black fin shark
(Also: Black tip; Black tip shark; Black-tip shark; Black-tipped shark; Blackfin shark; Blacktip Shark; Blacktip shark; Blacktip whaler; Common blacktip shark; Grey shark; Requiem shark; Shark; Small black tipped shark; Small blacktip shark; Spot-fin ground shark)

The blacktip shark is widespread in all tropical and subtropical continental waters. These waters include: the Western Atlantic Ocean (including the Caribbean Sea), the Eastern Atlantic, the Indo-West Pacific (Southeast Asia and Australian waters), Central Pacific (Hawaiian Islands), Eastern Pacific (Californian coast) as well as in the Red Sea (Compagno, 1984).

Blacktip sharks are common tropical, warm-temperate, inshore and offshore sharks (Stafford-Deitsch, 1987). They are often found on or near the continental and insular shelves. Blacktips are also commonly found close to the shore, in estuaries as well as river mouths (Stafford-Deitsch, 1987). They are also found in shallow muddy bays, mangrove swamps of high salinity, lagoons, coral reef dropoffs and in areas found far offshore (Compagno, 1984). Blacktip sharks usually stay in waters shallower than thirty meters and can handle freshwater environments but are rarely found in them (Compagno, 1984).

Blacktip sharks are relatively large sharks, grey in color with a long pointed snout. They have small eyes. The teeth are narrow, erect and narrow-cusped serrated upper anterolatheral teeth (Compagno, 1984). Blacktips lack an interdorsal ridge and have relatively large pectoral fins (Compagno, 1984). The first dorsal fin is large with a black tip on the rear. The second dorsal fin is much smaller yet contains a black tip as well. Usually, most fins on the black tip sharks contain black tips (with the exception of the tail-fin) (Stafford-Deitsch, 1987).

Female blacktips are viviparous and contain a yolk-sac placenta. The number of offspring per litter ranges from 1-10 (usually 4-7)(Compagno, 1984).

Gestation of the young lasts anywhere from 10-12 months (Compagno, 1984). The young are born in late spring or early summer. Pregnant females move inshore to drop their young in nursery and pupping grounds. Young are believed to be produced in alternate years by each female blacktip (Compagno, 1984).

Blacktip sharks fast-swimming sharks that often travel in schools. They are active and usually found in near surface waters of shallower marine areas (Taylor, 1993). Blacktips are often confused with related spinner sharks because of their feeding method. A blacktip often shoots itself through the surface water and can rotate up to three times around its axis snapping in all directions in hope of attaining food (Compagno, 1984).

Blacktips, at times, can be an aggressive species which approaches swimmers and divers. Aside from this behavior, very few blacktip attacks on humans have been documented. Moreover, blacktips are regarded as relatively harmless sharks.

Blacktip sharks are primarily fish eaters (Taylor, 1993). The prey species include a number of bony fishes including sardines, menhaden, herring, anchovies, ten-pounders, sea catfish, coronetfish, tongue-soles, threadfins, mullet, spanish mackeral, jacks, groupers, snook, porgies, mojarras, emperors, grunts, slipjaws, butterfish, croakers, soles, tilapia, triggerfish, boxfish and porcupine fish (Compagno, 1984). Occasionally blacktips even consume small sharks. They also consume other aquatic organisms such as guitarfish, skates, butterfly rays, stingrays, eagle rays, squid, cuttlefish, octopi, crabs and lobsters (Compagno, 1984). Blacktips are quite prone to feeding frenzies when there is competition between sharks for a common abundant food source (Stafford-Deitsch, 1987).

Blacktips are used as a food source for human consumption. Their hide can be used to make leather goods. Due to the high vitamin content of the liver oil, it is used for vitamins. The dead carcasses can also be used as fish meal (Compagno, 1984).

There have been instances of blacktip attacks on humans, though these instances are very rare. It is also common for blacktips to get caught in shrimp trawl nets (Compagno, 1984; Taylor, 1993).

As is true with many species of shark, blacktips have experienced reductions in their numbers. This is due to overfishing and killing of the shark. The blacktip however is still a relatively abundant species of shark and is currently not protected by federal law.