More than 300,000 watched live as April gave birth to a healthy male calf at around 12:45 p.m., the Animal Adventure Park in Harpursville, New York said.
Park officials say the newborn giraffe was on its feet by 1:27 p.m., and nursing by 1:51 p.m.
"Success! With an average 15-month gestation, we are thankful to have a healthy calf on the ground, nursing and bonding with mom," animal park owner Jordan Patch said. "With wild giraffe numbers plummeting annually, every calf born counts."
April drew more than 232 million YouTube live views during a seven-week period in 2017 before she gave birth to Tajiri That came as a surprise for the small zoo 130 miles (209 kilometers) northwest of New York City.
This is April's fifth calf and the second for her and Oliver, the dad of Tajiri and the newborn. A naming contest for the new calf will be held soon.
Fans will be able to see the little one face to face when Animal Adventure Park opens for the season on May 1.
Zoo officials said big brother Tajiri, meanwhile, is on his way to starting a family of his own. The park welcomed an adult female giraffe, known as Johari, in January.