Injuries to three Sea World trainers in three months prompted a decision Monday by park officials to temporarily halt stunts in which trainers join killer whales in their pool.
Jackie Hill, public relations director at the aquatic park, said she did not know when trainers will again join the whales in the water.
"I don't know how long it will be," Hill said. "We have to act according to our comfort level. Of course, we are concerned about John."
John Sillick, who has been a trainer at the park for two years, suffered internal injuries and fractured his ribs, pelvis and upper leg in an accident Friday.
A 12,000-pound killer whale landed on the trainer during a morning show.
Sillick, 26, remained in serious condition at University of California, San Diego, Medical Center after undergoing surgery twice over the weekend, a hospital spokeswoman said.
Trainer Chris Barlow was slightly injured on Sept. 30 after a whale bumped into him during a performance. Two days before, trainer Mark McHugh was bit on the hand by a whale during a training exercise.