Marine biologist Nan Hauser credits a 50,000 humpback whale for protecting her from a tiger shark while snorkeling recently.

Unknowingly to Hauser, a tiger shark was in the water nearby while she was interacting with the humpback whale during a dive off Muri Beach in Rarotonga, Cook Islands in October. The whale can be seen in the below video tucking her underneath its pectoral fin, although the shark is never clearly visible in the footage.

Hauser recently spoke to the Daily Mirror UK about the experience, saying, “I’ve spent 28 years underwater with whales, and have never had a whale so tactile and so insistent on putting me on his head, or belly, or back, or, most of all, trying to tuck me under his huge pectoral fin.”

Hauser was pushed around by the whale for nearly 10 minutes, as the whale also used its head and mouth to keep her away from the shark. The whale even lifts Hauser out of the water at one point.

Once Hauser spotted the shark she realized what the whale was doing and tried to stay calm to not startle the whale. As Hauser returns to the safety of her research boat, she informs her team of the shark and the whale surfaces again to check on her.

Hauser also told the Daily Mirror UK, “There is a published scientific paper about humpbacks protecting other species of animals, by Robert Pitman. For instance, they hide seals under their pectoral fins to protect them from killer whales. They truly display altruism — sometimes at the risk of losing their own lives.”

This footage is the first known video of a humpback whale protecting a human from a tiger shark.

The hero humpback whale saving Nan Hauser.

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