The incident was reported around 7:15 a.m., near Parson's Landing, according to lifeguards with the Los Angeles County Fire Department.
"The patient and their father were kayaking … when their boat was bumped by what is believed to be a shark of unknown size and type," lifeguards tweeted. "During the encounter, the patient reached their hand into the water and was bit by the animal."
The boy sustained a hand injury and was airlifted in stable condition to a local hospital for surgery. The father was not injured.
The teen was part of a Boy Scouts camp and was participating in a youth camp activity at the time of the attack, FOX 11 reported.
"Our camp staff quickly removed all participants from the water following this incident, and we have canceled all water activities as we work with Los Angeles County Fire Department," according to a statement from the Boy Scouts of America. "We provide a chase boat, which goes out before every water activity that takes place outside of Emerald Bay to identify potential weather and wildlife hazards and follows each group of participants back to shore. No hazards were spotted this morning."
The ocean was cleared and closed a mile in each direction from where the attack occurred, lifeguards said. The closure will remain in place for at least 24 hours.
Lifeguard officials added that they notified the California Department of Fish and Wildlife and the U.S. Coast Guard about the incident.
A shark expert from the Scripps Institute of Oceanography was also requested to identify the size and type of shark.