The maximum weight is over 500 pounds (230 kg). The size at birth is around 29 inches (75 cm). Females are larger than males, reaching a length of around 7.8 feet (2.4 metres) as adults, and weighing around 285 pounds (130 kg). This is the result of a longer lifespan of about 16 years, compared to 12 years for males. Males reach a length of around 7.3 feet (2.2 metres), and weigh 209 pounds (95 kg). The growth rates calculated from captive Bull sharks were estimated to be about 11 inches (28 cm) per year in the first years of life, slowing to half that rate after about 4 years of age.