"Tyra (the mother) went into labor at approximately 3:15 p.m. yesterday and delivered her baby 5:15 p.m.," said Houston Zoo Hoofed Stock Supervisor Laurie McGivern, in the release. "The as yet unnamed calf was standing on her own and nursing by 6:15 p.m."
The calf weighs 150 pounds and stands 6-foot-6 and is said to be healthy. This is 12-year-old Tyra's sixth calf.