SANTA ANA, Calif. >> Maria Korcsmaros was swimming just off the Southern California coast to get ready for her summer triathlon when something big gripped her side and then let go.

She knew immediately she had been bit.

The normally choppy water around her grew still and turned red with blood, Korcsmaros, a 52-year-old fitness instructor, recalled lifeguards telling her later after they pulled her from the ocean and whisked her to safety.

“I instantly knew it was some kind of fish, and probably a big fish, like a shark,” she told reporters from her bed at Orange County Global Medical Center in Santa Ana on Tuesday, nine days after the attack off the coast in Corona del Mar.

“It felt like a big bite and then it let go. And then I was like, ‘OK, I’ve got to get out of here,’ ” she said.

Since then, shark sightings closed beaches near the site of her attack twice in two days. Swimmers and surfers were allowed back in the water Tuesday morning, Huntington Beach officials said.

Shark bites are incredibly rare. But there are more great white sharks in the waters off California thanks to protective measures, and the human population has also grown, so occasional encounters happen, said Christopher G. Lowe, director of the Shark Lab at California State University, Long Beach.

On Tuesday, Lowe swabbed bite marks on Korcsmaros’ mangled wet suit to try to learn more about the shark. Ralph Collier of the Shark Research Committee said the shark was likely 9 or 10 feet long.

Korcsmaros, a mother of three, said she was lucky lifeguards were in a boat nearby. After the bite, she treaded water, raised her arms and hollered for help.

They put her in the boat and had her apply pressure to her arm to try to stop the bleeding. She said it was hard to breathe, but she was awake all the way to the hospital, where she had surgery.

Korcsmaros, a long-time triathlete who lives in the inland city of Corona, California, said she has seen dolphins and fish on her swims but never sharks. She didn’t perceive the wildlife around her as a threat but “a very interesting thing to be around.” Korcsmaros said.

While it will take time to recover, she hopes to get back in the water. She’ll just have to see how she feels upon returning to the ocean.

“I’ll probably start with my lake swims, and go from there,” Korcsmaros said from her hospital room adorned with bouquets, balloons and a teddy bear sporting her swim goggles. “But I want to train for another race, and I want to do another race.”