1. The Great Melt

The Arctic snow melt causes the arrival of millions of animals that now must share one habitat.

2. The Great Salmon Run

In British Columbia, Canada, the survival of carnivores like bears depends on the yearly salmon run.

3. The Great Migration

The animals drawn to the Serengeti plain after the annual rains must contend with carnivores.

4. The Great Tide

Cooling South African coastal waters draw billions of sardines and many ocean predators.

5. The Great Flood

The flooding of the Okavango River draws in wildlife, including both predators and prey.

6. The Great Feast

Faced with the journey across the Pacific to feed, a young humpback tries to survive.