Transcript for American tourist recovering after hippo attack

Now to the American tourist attacked by a hippo in Africa. The giant animal knocking her out of her canoe and dragging her under the water. Whit Johnson is here and how did she escape? Reporter: It's incredible. This woman fought back literally punching her way out of the hippo's mouth. A source close to the family telling us it was all part of a birthday adventure in Africa that nearly turned deadly. This morning, an American woman is lucky to be alive recovering from a vicious hippopotamus attack in Zimbabwe. Kristen and Ryan yaldor celebrating and the guide alerted the couple hippos were ahead on the right urging them to paddle left. That source saying the hippo who was apparently protecting her baby then got under their two-man canoe and launched the couple into the air. Ryan swimming to shore. But the hippo chomping down on Kristen's leg fracturing her femur, dragging her underwater. Kristen then punching the hippo repeatedly in the face before the massive mammal let her go. She was airlifted to a hospital after escaping. Her mother-in-law telling "The Tampa bay times" if one of those hit her femoral artery we would probably be planning a funeral today. By all accounts she was incredibly lucky. Hippos are vegetarians but highly territorial. Watch this. They can weigh up to 8,000 pounds, run 30 miles per hour and bite with the crushing force of one ton seen here devouring watermelons in a single snap. They are the deadliest large land mammal in the world killing about 500 people per year in Africa. And that source close to the family says the couple never intentionally approached the hippo and they were only following directions from their guide. Kristen has had two surgeries so far. More may be required but we can't emphasize enough, I mean, how incredibly lucky she was that it wasn't worse. I tell you what, I've done that before in the canoes and it was very -- Around the hippos. No, I didn't go around -- I stayed closer to the shore. You could see them. Oh, yeah, I could see them. I'll never do it again. I know now. Lesson learned. Yeah. Thank you, whit.

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