Whale watchers were making their way toward the U.S.-Canadian border in the Strait of Juan de Fuca when the captain spotted the group of whales. At first, whale watchers observed what they thought was a pod of roughly 15 Bigg’s orcas swimming and "being unusually active at the surface." Before long, it became apparent that two humpback whales were in their midst.

Intense

According to observers who came and went throughout the day, the intense encounter that unfolded included an astonishing three hours of breaching, tail-slapping and loud vocalizations.

For several years, scientists have suspected that orcas have been killing and eating parts of great white sharks. Now, they have video evidence to prove it.

New drone and helicopter footage show a pod of orcas ruthlessly pursuing a great white shark in Mossel Bay, South Africa for more than an hour before going in for the kill. The video culminates with one of the killer whales gobbling up a large chunk of the shark's liver.