Hammerhead Sharks are viviparous, meaning they give live birth. Females usually give birth to 12 to 15 pups at a time, but the Great hammerhead shark gives birth to around 20 to 40 pups at a time. Once they are born, baby Hammerhead sharks come together in groups and swim towards warmer waters. They stay together in groups until they are older and big enough to live on their own. Hammerhead shark live for around 20 to 30 years.