For the first time, scientists have captured video evidence of orcas cooperatively hunting whale sharks, the largest species of fish on Earth. This graphic footage proves that whale sharks are a regular part of some orcas’ diets, and solves the mystery of how they are able to kill the massive fish.

The method of hunting may imply that some orcas in the Gulf of California have acquired a special set of skills–like going after the ventral side of young whale sharks–that help them prey on these enormous fish. Orcas may have learned to do the same thing in other parts of the world, but evidence is limited, according to the team.

Off the coast of Mexico, scientists have observed a pod of killer whales adapting new skills to help them hunt these docile giants of the sea.