Newborn shark sizes vary by shark species; for example, a newborn great white is typically about 4 feet long, while blacktip reef shark newborns are considerably smaller, usually more than 20 inches in length. Whale sharks, which are quite large in adulthood, give birth to live pups rather than laying eggs, and these newborn pups are typically about a foot and a half long, or 21 to 25 inches in length. Growth rates subsequent to birth may also vary by species.
Blacktip reef sharks in captivity have exhibited rapid growth, with one captive specimen exhibiting an average growth of around 9 inches during its first 2 years alive. After this initial growth spurt, blacktip reef shark growth rates tend to slow considerably. Great white newborns typically grow about 10 inches per year, keeping up this growth pace until they reach maturity at age 10, at which point they can be 20 feet long or more.
On the other hand, shark embryos also vary in size. Whale shark embryos can range in length from about 16 to 15 inches, and their mothers, which are about 30 feet in length, can carry hundreds of eggs at once. Like whale sharks, great whites give birth to live pups.