Wildlife filmmakers Beverly and Dereck Joubert document an annual zebra migration in Botswana. Also: climate change creates challenges for the Pacific walrus; pronghorn antelope are followed in southern Wyoming.
Mali elephants embark on a 300-mile migration in West Africa; great white sharks travel from Hawaii to northern Mexico to reach an abundant feast; golden jellyfish of Palau follow the sun in their daily migration.
Elaborate mating rituals of different species are observed. Included: Australia's little red flying foxes; white-eared kob in Sudan; army ants in Costa Rica; elephant seals, penguins and black-browed albatross in the Falkland Islands.
Alec Baldwin narrates this seven-part series, which documents epic animal migrations on all seven continents. The premiere focuses on Christmas Island red crabs, which travel en masse from interior forests to mate on the beaches and deliver their young. Also: wildebeest are followed on an annual 300-mile journey across Kenya and Tanzania.