Whales

Bertie Gregory has been so focused on the large land animals of this place, he's hardly noticed what's lurking in the waters just off shore. So this week, he's on the hunt for the biggest animals in this ecosystem: whales and orcas, some of the most massive animals on Earth. Even though we can only see their tails and dorsal fins, experts can identify them on sight, and Bertie makes some pretty incredible discoveries about these giants' past.