Humpback whales intervene in killer whale hunt

Found via Naked Capitalism.

A BBC/National Geographic film crew have recorded rare footage of humpback whales intervening in a killer whale hunt.

Gray whales migrating along the coast of California, US are often targeted by orcas.

One mother and calf's journey was being filmed for the BBC series Planet Earth Live when the third party became involved in the drama.

Onlookers suggest they were deliberately disrupting the hunt.