Kalia, a 9-year-old orca at SeaWorld San Diego, is pregnant with her first calf, park officials announced Tuesday.
Kalia mated with Ulises, the park's oldest male, thought to be in his 30s. To make sure that Kalia was pregnant, she was also artificially inseminated with Ulises' sperm.
A bill now stalled in the state legislature would ban the park from breeding its orcas.
The bill, which would also ban orca shows, has been sent by an Assembly committee for "interim study," an ill-defined process that could take a year or longer.
Supporters of the bill, inspired by the documentary "Blackfish," oppose captive breeding of orcas.
But SeaWorld officials Tuesday said the breeding program helps researchers study the orcas' estrous cycles and gestation and also "enriches the lives of our animals by allowing them to experience, interact with and help raise another member of their pod."
The park has had six orca births, including Kalia in 2004.
Kalia is expected to give birth in December. Orcas have a 17-month gestation.