Watch Nature Season 22 Episode 4 Online

Each year, in the late summer, a region known as the Red Triangle bustles with marine mammal activity. Lying between San Francisco and Monterey, the Red Triangle includes beaches where elephant seals go to molt, and offshore sites where great whites feed on unwary prey. When not prowling the Red Triangle, great white sharks search the kelp forest for sea lions, or roam the open ocean. Their migration is predictable. Each year they turn up at the same place at the same time, occasionally crossing paths with humans who still swim and surf in these dangerous waters.