Life Cyle of Bull Sharks

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REFERENCES

Female bull sharks can give birth to as many as 13 young sharks, around 55 to 85 cm in length, known as pups. To give birth, these sharks typically move towards shallow, sheltered waters such as river mouths and estuaries. Once born, the mother shark immediately abandons her pups, leaving them to fend for themselves in coastal nursery habitats. These habitats are usually located in freshwater systems, serving as a protective environment for the pups against other adult sharks. The pups remain in these protected waters until they are large enough to defend themselves against potential predators.

PUPS

Bull sharks are formidable species known for their robust build, aggressive behavior, and solitary hunting nature. Their ability to thrive in saltwater and freshwater habitats makes them stand out. Their tendency to inhabit coastal areas and rivers, especially in popular swimming and fishing spots, makes them one of the most dangerous species to humans.

INCUBATION & GESTATION (VIVIPARITY)

Unlike other shark species, bull sharks have a relatively short incubation and gestation period. After mating, the female bull shark carries fertilized eggs inside her body for about ten to twelve months. During this time, the embryos develop within a yolk sac, receiving nutrients and oxygen until they are ready to hatch.

FERTILIZATION

Bull sharks are viviparous; females give birth to live offspring, typically an average of eight to ten baby sharks at once. Bull sharks reproduce through internal fertilization, with the embryos developing inside the mother's body. The fertilized eggs remain inside the female's body until the young are ready to survive independently.

Sub-adult bull sharks are those who have not yet reached adulthood. During the early stages of their life cycle, they experience rapid development, but this slows down as they mature. Bull sharks typically spend the first five years of their lives in river mouths before moving on to their preferred habitat. While most sharks don't mature until they are between 15 and 30 years old, the timeline can vary between species. For example, bull sharks reach maturity between the ages of eight and ten, though it can take up to 20 years to become sexually mature in some cases.

SUB-ADULTS

Bull sharks reach adulthood at the final stage of their life cycle. At this point, they become capable of reproducing. It usually takes them 8 to 10 years to reach sexual maturity. Male bull sharks have pelvic fin extensions called claspers, which they use to transfer sperm to female sharks. During mating, the male expels sperm, and the eggs fertilize inside the female's body. After a pregnancy of 10 to 11 months, female bull sharks give birth to live young, usually 1 to 13 in number. These sharks can live up to 20–30 years and are known to hunt independently, reaching up to 43 miles per hour of speed while on the hunt.

ADULTHOOD