California beaches are closed after numerous shark appearances and attacks in the past weeks have been reported. The closing on Sunday affected Sunset Beach and Surfside Beach.

A helicopter commissioned by the Orange County Sheriff's Department spotted three 10-foot sharks 150 yards from the shoreline.

The act is a precaution to beachgoers because the sharks are huge and potentially aggressive. This event happened a week after a shark attack on a 52-year-old fitness worker, Maria Korcsmaros during Memorial Day weekend.

Korcsmaros was training for an upcoming triathlon. She was swimming about 2.5 kilometers from the shore when she was attacked at Newport Beach, California. She contracted a shark bite in her middle body region, multiple rib fractures and pierced lung. She was taken to a nearby hospital for surgery.

The wound was obviously sustained from a shark bite, Korcsmaros' physician at the Orange County Global Medical Center Dr. Philip Rotter told MyNewsLA. The individual marks from the teeth are apparent. Her fit lifestyle might be the reason she survived the ordeal.

The bites suggest that the size of the attacker is about 10 feet. Chris Lowe from the Shark Lab at Long Beach told the Associated Press that it is most likely a great white shark. The shark responsible for the attack has not been found.

Korcsmaros is fine now. She has a picture released on Friday of her smiling on the hospital bed.

Researchers pinpoint two contributions of humans to the recent shark attacks: increasing human population and increasing ocean temperatures. Humans have been so adventurous as of late that there are more swimmers daring to invade shark territories. Also, the warming ocean (climate change caused by human activities) forces the sharks to follow their prey's migration away from the equator. In turn, the sharks are seen near coastlines.