Shallow Seas

A humpback whale mother and calf embark on an epic journey from tropical coral paradises to storm ravaged polar seas.
Newly discovered coral reefs in Indonesia reveal head-butting pygmy seahorses, flashing 'electric' clams and bands of sea kraits, 30-strong, which hunt in packs. Elsewhere plagues of sea urchins fell forests of giant kelp. Huge bull fur seals attack king penguins, who despite their weight disadvantage, put up a spirited defence.

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S01E10 - Seasonal Forests