PHILADELPHIA (CBS) -- There was a big birthday bash for Button the hippopotamus Wednesday at Adventure Aquarium in Camden.
It was Button the Nile hippopotamus' 20th birthday. Guests watched as Button and gal pal Genny enjoyed melons stuffed with vegetables.
Ten-year-old Cameron Culbertson was enjoying the party with his 4th grade class from Fountain Woods Elementary School in Burlington Township.
"I think they are pretty cool," he said, "because they eat a lot and they like to swim."
Cameron's classmate, 10-year-old Sean Story, knows some things about hippos.
"I think they are herbivores," he said. "And they also don't let any animal cross their territory."
Vince the porcupine was also invited to the party having tons of fun munching alongside the hippos.
Visitors also got to sign a giant card for Button. The party extends into the weekend at Adventure Aquarium.
Nile hippos are considered threatened. Button and Genny serve as ambassadors for their species in the wild, sparking conversation about conservation.
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