The last orca has been born in captivity at a SeaWorld park in San Antonio just over a year after the theme park decided to stop breeding orcas following animal rights protests and declining ticket sales.
The Orlando-based company said the orca, the last in a generation of whales bred in confinement, was born yesterday.
SeaWorld did not immediately name the calf because the park's veterinarians had not yet determined whether it was male or female.
The mother, 25-year-old Takara, was already pregnant when SeaWorld announced in March 2016 that it had stopped breeding its orcas. The gestation period for orcas is about 18 months.
Earlier, SeaWorld's chief zoological officer, Chris Dold, told The Associated Press he expected the birth to be bittersweet, the last such event at any of the parks.
But hours after the birth yesterday, Dold said, SeaWorld staff only felt like celebrating.
SeaWorld said mother and calf both appear healthy.
"These are extraordinary moments," he said by phone while travelling to the US from Abu Dhabi, where SeaWorld is developing its first new park without orcas.
SeaWorld decided to stop breeding orcas and phase out its world-famous killer whale performances by 2019, after public opinion turned against keeping orcas, dolphins and other animals in captivity for entertainment.
The backlash intensified after the 2013 release of "Blackfish," a documentary critical of SeaWorld's orca care.
It focused on the orca Tilikum, which killed trainer Dawn Brancheau in Orlando in 2010, dragging her into the pool before shocked visitors after a Dine with Shamu show.
Tilikum, which sired 14 calves over nearly 25 years in Orlando, died of bacterial pneumonia in January.
The newborn calf was sired by Kyuquot at the San Antonio park by natural means, bringing SeaWorld's orca population in the US to 23.
All the orcas are expected to remain on display and available for researchers for years to come in Orlando, San Diego and San Antonio.
SeaWorld has said it will introduce new "natural orca encounters" in place of theatrical shows.