ORLANDO, Fla. — SeaWorld will stop its orca breeding program, the company announced Thursday, after years of controversy over keeping its orcas in captivity and discomfiting drops in attendance at its theme parks and the value of its stock.

The sweeping change to SeaWorld Entertainment's business model also will include ending theatrical shows nationwide, to be replaced by exhibits highlighting whales' natural behaviors. SeaWorld had already planned that in San Diego. SeaWorld Orlando will follow in 2019.

SeaWorld had previously agreed not to take more wild-caught cetaceans, meaning this should be its last generation of killer whales. The orcas it already owns — including one that became pregnant last year — will continue living at SeaWorld, likely for decades. The company has 29 orcas. Six of the whales are in a Spanish theme park.

“I've struggled with this decision more than any other decision I've made in business,” Chief Executive Joel Manby said Thursday. “I feel relieved. I think the company now can double down on growing the business and focus on positive, energetic, inspirational and creative things again.”

For decades, SeaWorld has been beset by criticism from animal advocates, and it has never fully recovered from the 2013 documentary “Blackfish,” which accused the company of neglecting and abusing the orcas.

SeaWorld dismissed the criticism and disputed the documentary's allegations for years — until it became clear that, from a business perspective, change was inevitable.

“They had to evolve because they wanted to continue to make money,” said Wendy Patrick, a business ethics lecturer at San Diego State University.

It was only last year, after reporting park attendance dropped 4 percent in 2014, that SeaWorld began to acknowledge “public perception” was hurting its bottom line. The company launched a $15 million campaign to repair its image and pledged to spend up to $100 million to double the size of its San Diego orca enclosure.

Still, until Thursday, SeaWorld stood firm about continuing to breed the animals. As recently as late December, its San Diego park sued the California Coastal Commission for including a no-breeding condition on its approval of the larger orca enclosure.

Investors cheered the company's decision to stop its breeding program. Its stock closed at $18.72 on Thursday, up 9.3 percent.

Manby said that most reproduction at SeaWorld happens naturally, and “we have birth control medication, basically.” He referred further questions to the company's chief veterinarian, Chris Dold, who said in an emailed statement that the company would use a combination of contraception and “social management.”

SeaWorld's decision means the company is forcing itself to envision a future without orca shows, its most popular attraction, said Martin Lewison, a theme parks expert and assistant business professor at Farmingdale State College in New York.

After Manby became CEO of SeaWorld last year, he began moving the company in a direction toward emphasizing its conservation and rescue work. Last year, SeaWorld announced it would end theatrical orca shows at its San Diego park, which has taken the biggest hit from the controversy over its captive orcas.

Manby said SeaWorld's decision reflects society's changing views about animals in performances.

Last year, Ringling Bros. Barnum & Bailey Circus announced it would retire its elephants — then in January announced it would move up the date by two years. Universal Studios stopped using orangutans in its Animal Actors shows, and other aquariums have eliminated or scaled back on dolphin shows.

As SeaWorld moves forward, it has the backing of a longtime adversary, The Humane Society of the United States. The two announced a partnership Thursday.

“Blackfish” director Gabriela Cowperthwaite was among the animal advocates who cheered SeaWorld on Thursday. “This is a defining moment,” she said in a news release. “The fact that SeaWorld is doing away with orca breeding marks truly meaningful change.”

But not everyone was satisfied by SeaWorld's announcement. The company's most vocal critic, People for the Ethical Treatment of Animals, said in a statement that “SeaWorld must open its tanks to the oceans to allow the orcas it now holds captive to have some semblance of a life outside these prison tanks.”

spedicini@tribpub.com