Did notoriously aggressive orcas just save a humpback whale from certain death?

In some extraordinary drone footage, whale researchers appear to have seen a pod of orcas helping to free a humpback whale from rope line that was entangling its tail.

At first, researchers from Whale Watch Western Australia thought that the orcas were there to attack and kill the humpback whale, which was visibly injured and weakened–precisely the kinds of easy kills that predators like orcas rarely pass up.

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