Bull Shark Fact Sheet

Appearance:
Stocky to very heavy-bodied species. Very short and broadly rounded snout. Small, circular eyes. First dorsal fin large and broadly triangular to somewhat falcate. Origin of the first dorsal fin usually over or just behind the insertions of the pectoral fins. No interdorsal ridge.

Coloration:
Pale to dark grey. Fin tips are dusky, but not strikingly marked. An inconspicuous white band on the flanks.

Distribution:
Widespread along the continental coasts of all tropical and subtropical seas. Travels far up warm rivers (Mississippi, Amazon River, Zambezi River) and freshwater lakes (Lake Nicaragua, Lake Ysabel). Western Atlantic: Massachusetts to southern Brazil. Gulf of Mexico. Caribbean Sea, Bahamas. Eastern Atlantic: Morocco, Senegal to Angola. Western Indian Ocean: South Africa to Kenya, Iraq and India. Western Pacific: Thailand, Viet Nam, Borneo, New Guinea, Australia, New Caledonia, Fiji, Rangiroa Atoll, the Philippines. Eastern Pacific: Southern Baja California and Gulf of California to Ecuador.

Biology:
Found close inshore in water less than 30 m deep and occasionally less than a meter deep, but ranging down to 150 m. It is the only shark that penetrates far into fresh water and apparently is able to exist there. Bull sharks are not able to maintain an entire life cycle in fresh water. In marine habitats this species commonly occurs in hypo- and hypersaline lagoons and bays.

Feeding:
Opportunistic feeder, with a very broad food spectrum. Favoured food includes bony fishes and elasmobranchs (rays and other sharks, sometimes even other bull sharks) but feeds on sea turtles, birds, and dolphins.

Size:
Maximum about 340 cm (females); males reach about 300 cm.

Reproduction:
Viviparous, with a yolksac-placenta. Gestation period is between 10 and 11 months. 1 to 13 pups per litter. Size at birth between 55 and 80 cm. Pups show a very slow growth rate. Males mature between 160 and 230 cm, females mature between 180 and 230 cm. Expected life span at least about 14 years.

Similar species:
None.

Endangerment:
It is a very important fisheries species and therefore must be considered as threatened.