The blacktip reef shark, Carcharhinus melanopterus, is a common inhabitant of shallow, inshore waters across the tropical Indian and Pacific Oceans. This species is frequently observed over reef ledges and sandy flats, making its distinctive black-tipped dorsal fin a familiar sight in these marine environments. Understanding the typical size of this shark helps appreciate its role within the diverse ecosystems it calls home.
Blacktip Reef Shark Dimensions
Adult blacktip reef sharks typically reach an average length of about 1.6 meters (5.2 feet). Maximum recorded lengths are up to 1.8 meters (5.9 feet), with rare instances of 2.0 meters (6.6 feet). These larger sizes represent the upper limit of their growth potential.
Maximum recorded weights vary, with the International Game Fish Association listing 13.6 kilograms (30 pounds) and other accounts suggesting up to 24 kilograms (53 pounds). At birth, blacktip reef shark pups are small, measuring between 33 and 59 centimeters (13 to 23 inches) in length.
Sexual dimorphism is evident, with females generally larger than males. Males typically mature at lengths between 95 and 105 centimeters (37 to 41 inches), while females mature at a slightly larger size, usually between 97 and 110 centimeters (38 to 43 inches).
Influences on Size
Several factors contribute to the variations observed in the size of blacktip reef sharks throughout their lives. Age plays a significant role, with growth being initially rapid after birth. A documented captive shark showed an average growth of 23 centimeters (9.1 inches) per year during its first two years. This rapid growth phase slows considerably as the shark matures, typically reducing to around 5 centimeters (2.0 inches) annually for juveniles and adults.
Sexual maturity also influences size, as males typically reach this stage around 4.2 to 8 years of age, while females mature later, usually between 8.5 and 9 years old. The lifespan of blacktip reef sharks in the wild generally ranges from 10 to 15 years, though some individuals in controlled environments have lived for over 25 years. These age-related growth patterns contribute to the overall size range observed in the population.
Habitat quality and food availability are additional environmental factors influencing blacktip reef shark size. Regional variations in size at birth, maturity, and maximum size have been noted, suggesting local conditions play a part in their development. For example, sharks in smaller, isolated atolls may exhibit smaller maximum sizes compared to those in larger coastal habitats, possibly due to differences in food resources.