White Shark (Carcharodon carcharias) photo courtesy Howard Hall Natural History of the White Shark

Range: White Sharks are found in temperate waters around the world. They are most often seen in waters off of large seal and sea lion colonies. Major world wide concentrations occur off South Africa, Austrailia, California, New England and the Mediterranean. We now know they are capable of migrating large distances so for all we know, White Sharks may be travelling between these areas.

Breeding: As recently documented at the Farallones female White Sharks appear to give birth only every other year. In the North Pacific pregnant females have been recorded off Japan but not off California suggesting that the California female sharks may migrate to the west Pacific to breed. Litter size ranges from 4-11 pups, which are born live (referred to as ovoviviporous). The annual reproduction rate therefore is only 2-6 pups per year, a very slow reproductive rate.  Slow reproduction rates are why sharks are very vulnerable to overfishing.

Feeding: Until White Sharks reach about 10 feet in length, they feed exclusively on fish, including skates, rays and other sharks. Once over 10 feet (about 10 years of age) their teeth change shape from pointed and needle like to broad and triangular with sharp cutting edges. This allows their diet to shift to marine mammals including seals, dolphins and whale carcases. White Sharks are visual predators that ambush live prey from below.

Life Span: We do not know how long White Sharks live. We have observed several adult sharks at the Farallones for over 15 years, and they do not seem to have changed in appearance. White Sharks do not breed until they are 15 years of age or older, and other animals that defer breeding this long live to be 50-100 years old. We will be able to predict longevity using mark-recapture analysis.

Behavior Notes: White Sharks are thought to be solitary in their travels, although they form loose groups in feeding areas.  White Sharks must continue to swim at all times or they drown. No one has ever observed White Sharks copulating. Females at the Farallones exhibit bite scars along their gills, assumed to be recieved from males during copulation. Human Interactions: Documenting White Shark attacks along the California coast from 1973 to 1992, John McCosker and Bob Lea authenticated only 43 on humans, mostly surfers and snorkelers; fewer than 10% of these (only four in 20 years) were fatal. Until 1993 it was legal to fish for White Sharks off of California, but PRBO helped draft a state bill to   protect them from hunting in California waters. Because of their slow reproductive rate they are very sensitive to disturbance. We are currently recommending regulations to protect the White Shark from disturbance due to "Adventure Tourism" at the Farallones.