FOX59 live-streamed the birth on Facebook.
April has taken time to clean her child and herself in the minutes following the birth.
Officials said the newborn giraffe, April's fifth and her second with her current mate, Oliver, was on its feet by 1.27pm, and nursing by 1.51pm.
When this latest pregnancy was confirmed, April's due date was merely "spring 2019", but the park was able to make a more precise guess later in the year, expecting the giraffe to give birth sometime in March. "With wild giraffe numbers plummeting annually, every calf born counts".
The mother was seen licking the newborn as park employees looked on in excitement from outside the animal's pen. "Upon Jordan's entry to the barn, April stood up and revealed that she had in fact been in labor and the calf's hooves and first 8-10" of leg were emerging!"
Viewers of the live stream reacted with delight at the sight of the animal giving birth.
April the giraffe delivers calf in front of worldwide audience
"I don't know why I'm crying happy tears", said Jennifer Hodell in the YouTube comments section.
"We need chocolate", said Susan Sapp.
April gave birth to a baby male calf, who is yet to be named, at 12.40pm EST at the Animal Adventure Park in Harpursville, New York.
Animal Adventure Park has been keeping a keen eye on April as she prepared for her birth.
April most recently gave birth to her fourth calf "Taj" in April 2017. Animal Adventure Park in NY said on Facebook in announcing the male calf's birth. She enjoys carrots and painting.
There are approximately 90,000 giraffe in the wild. About 1,200 giraffe are in captive management programs, the park said.