OKLAHOMA CITY - A major milestone was reached at the Oklahoma City Zoo on Labor Day.
It's now home to the second-oldest pygmy hippo in the U.S.
"He is a great old man but he has his moments where he can be a bit crabby," said Tracey Dolphin, curator of hoof stock.
But when you're one of the oldest of your species - that's OK.
To celebrate Wolee's 45th, he had his favorite snacks, like peanut butter with raisins and romaine lettuce.
The pygmy hippo was surrounded by fans who have different taste buds.
"It's gross," said young fan Milena Bush.
But share a love of one birthday tradition.
"Open the present," said party attendee Jack Smith.
Caretakers say it's rare to see a pygmy hippo reach this milestone.
"Actually the life, median, expectancy for hippos is 27 years," Dolphin said.
In fact, it's becoming more and more rare to see pygmy hippos at all.
Dolphin says there's only about 2,000 of them left in the wild.
So through Wolee and others like him, they're hoping they can alleviate the problem.
"The Oklahoma City Zoo is a conservation organization so the animals you see here we can gather research on, that will help their wild counterparts in the wild," said Dolphin.