Size6-7.5 feet (2-2.3 m)
DietFish, squid, pelagic crabs, nautilus
RangeAtlantic, Pacific and Indian Oceans
HabitatContinental and insular shelves, over deep water reefs and in open ocean, slope and shallow, coastal waters
- The body is large and slim with a moderately long, rounded snout, large eyes, and small jaws.
- Coloration can vary greatly in this species. The dorsal surface may have a bronze tint and can range in color from dark brown to blue-gray or dark gray. The ventral surface is white.
- Defining characteristics include small, densely-packed dermal denticles and notched, or serrated, teeth.
- The size and density of the dermal denticles give the shark’s skin a smooth or “silky” texture.
- The first dorsal fin is small and rounded. The second dorsal fin is small with a long, trailing tip. Pectoral fins are elongated and sickle-shaped.
- Common length for adult females is 7-7.5 feet (2.1-2.3 m); common length for adult males is 6-7 feet (2-2.1 m).
- The maximum recorded length is 11.5 feet (3.5 m).
- The maximum recorded weight is 802 pounds (364 kg).
A silky shark's maximum recorded weight is 802 pounds (364 kg).
- Generalist carnivore; diet consists of various species of fish, squid, pelagic crabs, nautilus and chub mackerel.
- Variation in their diet depends on the abundance and availability of prey. Opportunistic feeder when prey abundance is low, often consuming a wide variety of prey from different habitats and depths in the open ocean.
- Juveniles feed primarily on jumbo squid while adults feed on red crabs, chub mackerel, yellowfin tuna, albacore, mullet and porcupine fish.
- Highly migratory species, often following the movements of schooling fish such as tuna.
- Occurs in tropical and subtropical waters in the Atlantic, Pacific and Indian Oceans.
- Western Atlantic Ocean from Massachusetts to southern Brazil including the Gulf of Mexico and the Caribbean Sea to Uruguay.
- Eastern Atlantic Ocean from Madeira, Spain to northern Angola, S. Paul’s Rocks, and Cape Verde.
- Western Indian and the Red Sea from Tanzania to Mozambique including Madagascar and the Comores.
- Eastern Indian Ocean from the Maldives and Sri Lanka to western Australia.
- Indo-Pacific from China to New Zealand and the Caroline, Hawaiian, Phoenix, and Line Islands.
- Eastern Pacific Ocean from southern Baja California, Mexico to northern Chile.
- Highly migratory species.
- Found on continental and insular shelves, over deep water reefs and in open ocean, slope and shallow, coastal waters at depths between 60-165 feet (18-50 m).
- Prefers warmer waters of about 74°F (23°C)
- Reproductive maturity is reached at 7-9 years of age and 7-7.5 feet (2-2.3 m) in length in females; 6-7 years and 6-7 feet (1.8-2.1 m) in males.
- Sharks in the Indian Ocean and in the Pacific Ocean achieve maturity at younger ages and at smaller sizes than sharks in other areas (approximately two years younger and 1-2 feet (0.3-0.6 m) shorter).
- Viviparous; give birth to live young.
- Breeding takes place year-round in tropical waters and in summer months (June, July and August) in warm-temperate waters.
- The average gestation period is 12 months.
- Litter number varies by geographic location, litter size can range between 2-14 pups.
- Pups may spend the first few months of life near reefs or in nursery areas until their first winter when they move to the open ocean.
- Listed as “Vulnerable” on The IUCN Red List.
Grzimek’s Animal Life Encyclopedia. Thoney, D. A. and Loiselle, P. V.
Sharks and Rays of Australia. Last and Stevens