SeaWorld plans to fight a decision by the California Coastal Commission that bans the breeding of killer whales in captivity, a condition that the agency attached to its approval of a multimillion-dollar expansion of the whale habitat in San Diego.

The company said that the commission overreached its mandate when it added the restrictions during a hearing last week. The discussion, the company said, should have focused on land use, not animal husbandry.

The statement released on Thursday by SeaWorld Entertainment was referring to a decision that went to the heart of one of the San Diego marine theme park’s main attractions: the 11 killer whales, or orcas, that are on display and perform there. The commission’s decision, which halted the breeding of the whales and called into question the future of the shows, had been applauded by animal-rights activists.

SeaWorld had sought approval for a $100 million endeavor called the Blue World Project, which planned for a habitat with a depth of 50 feet, doubling the water volume of the existing facility. It was expected to be open to the public in 2018.