Despite being on birth control, the 10-year-old went into labor at 1 p.m. on Halloween. She gave birth to a healthy calf two and a half hours later.
Zoo officials are, of course, thrilled with the new addition. This is the first hippopotamus calf the zoo has had in 26 years. As a part of their Species Survival Program, they'd put Mara on birth control in the hopes that, eventually, she would mate with new father, 3-year-old Adhama.
Zoo staff had become suspicious that Mara was in a family way after some otherwise inexplicable weight gain. They had no way of confirming this "oops!" pregnancy, however. Still, they went ahead and estimated a mid-November due date for her, based on the species' eight-month gestation period. The baby, which lucky onlookers witnessed being born, is a healthy size and, by all estimates, full term, the zoo reported.
Mara is a relatively new Los Angeles transplant. She arrived in L.A. less than a year ago (um, eight months give or take). Her companion, with whom zoo officials say Mara made an immediate connection (clearly!), came up from the San Diego Zoo last year in June.