Facing criticism over their treatment of marine mammals, SeaWorld says it will stop breeding killer whales and those currently at its parks would be the last. (Reuters)

Embattled theme-park operator SeaWorld is ending its controversial captive-breeding program for orcas, meaning the killer whales in its care “will be the last generation of orcas at SeaWorld.”

The company said Thursday that it is ending “all orca breeding” immediately, putting an end to a practice animal rights activists have called inhumane — and that already had been prohibited by officials in California.

“Why the big news?” the company said in a statement. “SeaWorld has been listening and we’re changing. Society is changing and we’re changing with it. SeaWorld is finding new ways to continue to deliver on our purpose to inspire all our guests to take action to protect wild animals and wild places.”

SeaWorld has been under intense scrutiny over its treatment of captive killer whales since the highly critical 2013 documentary “Blackfish,” which spotlighted the animals’ living conditions and the dangers posed to their handlers.

The company’s chief executive resigned in December 2014 after months of declining revenue and attendance at its 11 parks across the United States. Last year, SeaWorld announced the end of its iconic killer whale shows in San Diego.

The California Coastal Commission said in October that SeaWorld would not be permitted to breed the animals in captivity. The new breeding restrictions — announced as the commission approved an expansion of SeaWorld San Diego’s killer whale habitat — made it likely that the orcas currently in captivity would be among the company’s last; SeaWorld has now made it official.

“This announcement reaffirms our commitment to not collect marine mammals from the wild,” the company said. “After all, we haven’t collected an orca from the wild in almost 40 years, and the orcas at SeaWorld were either born there or have spent almost their entire lives in human care.”

Animal welfare groups praised Thursday’s announcement.

The Humane Society of the United States, which partnered with SeaWorld on its new policies, said it was glad the company is taking steps toward better practices.

“Today’s announcement signals that the era of captive display of orcas will end and that SeaWorld will redouble its work around rescue and rehabilitation of marine mammals in crisis and partner with us to tackle global threats to marine creatures,” Humane Society president and chief executive Wayne Pacelle said in a statement.

The Animal Welfare Institute called the announcement “a monumental and important first step forward in achieving a more humane business model for the company.”

The orcas currently in captivity will not be released into the wild.

SeaWorld said its orcas will remain at the theme park “for many years to come.”

SeaWorld Parks and Entertainment president and chief executive Joel Manby said in an op-ed published by the Los Angeles Times that “some critics want us to go even further; they want us to ‘set free’ the orcas currently in our care. But that’s not a wise option.

“Most of our orcas were born at SeaWorld, and those that were born in the wild have been in our parks for the majority of their lives. If we release them into the ocean, they will likely die. In fact, no orca or dolphin born under human care has ever survived release into the wild. Even the attempt to return the whale from ‘Free Willy,’ Keiko, who was born in the wild, was a failure.

“For as long as they live, the orcas at SeaWorld will stay in our parks. They’ll continue to receive the highest-quality care, based on the latest advances in marine veterinary medicine, science and zoological best practices.”

People for the Ethical Treatment of Animals (PETA), a longtime SeaWorld antagonist, said Thursday that the company should “open the tanks to the oceans” to give the orcas “some semblance of a life outside their prison tanks.”

SeaWorld has made several recent announcements about changing long-standing procedures.

Just last month, SeaWorld said that its employees have posed as animal rights activists and vowed to stop the practice, following accusations that the company sent a worker to infiltrate a prominent animal welfare organization and incite violence among protesters.

Reps. Adam Schiff (D) and Jared Huffman (D), both of California, introduced last year the Orca Responsibility and Care Advancement Act, a bill would phase out the captivity of killer whales.

Indeed, the lawmakers said, killer whales have not been captured and imported from U.S. waters since 1976 or in international waters since 2001, though U.S. federal law still allows it with proper permits.

“For far too long, these intelligent mammals have been subjected to the heartwrenching practice of being kept captive in cruelly small tanks solely for public entertainment value,” Huffman said Thursday in a statement. “After years of public outcry and many letters, meetings, amendments, and even legislation, I am thrilled to see the wave of opposition build to where SeaWorld finally has done the right thing and ended their captive breeding program of orcas.”

Said Schiff: “These changes are something that advocates have been urging for years, and I think SeaWorld will find that visitors will reward their actions with a renewed interest in the parks.”

SeaWorld currently has 29 orcas in its care — seven in Orlando, five in San Antonio, 11 in San Diego and six in Spain’s Loro Parque.

Among the company’s best known animals is Tilikum, a killer whale that was the focus of “Blackfish,” the documentary that inflamed the SeaWorld backlash. Tilikum had killed one of his trainers and is associated with two other deaths.

SeaWorld Orlando announced last week that Tilikum is suffering from an illness that may take his life.

SeaWorld's killer whale, Tilikum, has become increasingly lethargic in recent weeks. The SeaWorld veterinary and animal care teams are concerned that his health is beginning to deteriorate. (Video: SeaWorld/Photo: Mathieu Belanger, Reuters)

This story has been updated.

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