Planet Earth2006

Himself - Narrator:
Over 90% of the living space for life on our planet is in the oceans. Home to the biggest animal that exists, or has ever existed. The blue whale. Some weigh nearly 200 tons, twice the size of the largest dinosaur. Despite their great size, we still have little idea of where they travel in the vast oceans. And none at all of where they breed.

Himself - Narrator:
The largest animal on Earth feeds almost exclusively on one of the smallest; krill, shrimp-like crustaceans. They take many tons of water into their ballooning throats in a single gulp and sieve out what it contains. Every day, each one swallows some four million krill.