From Wikipedia

David Attenborough

Planet Earth
Episode Nine

Shallow Seas

This programme is devoted to the shallow seas that fringe the world's continents. Although they constitute 8% of the oceans, they contain most marine life. As humpback whales return to breeding grounds in the tropics, a mother and its calf are followed. While the latter takes in up to 500 litres of milk a day, its parent will starve until it travels back to the poles to feed — and it must do this while it still has sufficient energy left for the journey. The coral reefs of Indonesia are home to the biggest variety of ocean dwellers. Examples include banded sea kraits, which ally themselves with goatfish and trevally in order to hunt. In Western Australia, dolphins 'hydroplane' in the shallowest waters to catch a meal, while in Bahrain, 100,000 Socotra cormorants rely on shamals that blow sand grains into the nearby Persian Gulf, transforming it into a rich fishing ground. The appearance of algae in the spring starts a food chain that leads to an abundant harvest, and sea lions and dusky dolphins are among those taking advantage of it. In Southern Africa, as chokka squid are preyed on by short-tail stingray, the Cape fur seals that share the waters are hunted by the world's largest predatory fish: the great white shark. On Marion Island in the Indian Ocean, a group of king penguins must cross a beach occupied by fur seals that do not hesitate to attack them.