ABSTRACT
A review of studies focused on White Sharks (Carcharodon carcharias) in the northeastern Paci¢c, together with new data, has allowed for a revised regional hypothesis for the life history of this species. Current evidence suggests that White Sharks in the northeastern Paci¢c begin their life in the nearshore, shallow waters of the Southern California Bight and Baja California. During their ¢rst winter, they may migrate to the warmer waters of coastal Baja California. As the juveniles grow, they gain the ability to remain in cooler water, exploiting deeper depths and migrating north of Point Conception. As they continue to grow, their diet changes from one dominated by ¢sh and invertebrates to one dominated by marine mammals. As White Sharks approach maturity, they begin annual (in the case of males) and bi-annual (in the case of females) migrations between offshore habitats and two known adult aggregation sites, one located off central California in the United States and the other off Guadalupe Island, Mexico. Males from both aggregation sites travel to a Shared Offshore Foraging Area, whereas females roam a much larger and less de¢ned offshore habitat. Both males and females may go to the Hawaiian Islands. Indirect evidence suggests that mating occurs at the adult aggregation sites. After more than 15 months at sea and an approximately 18-month gestation period, pregnant females return to coastal regions off Southern California, United States, and Baja California, Mexico, to give birth. Parturition occurs primarily between May and August, after which females return to one of the two adult aggregation sites. The understanding of this species’ migration patterns and reproductive biology was advanced through capture and satellite-linked radio transmitting tagging of adults, as well as the direct examination of claspers and the screening of blood samples for the presence of circulating reproductive hormones.
