BUFFALO, N.Y. -- Monday was a special day for a 400-pound gorilla at the Buffalo Zoo.

Koga, the zoo's silverback, turned 30 and so the Buffalo Zoo threw him a party — complete with decorations, presents, a cake, some special treats, and even a "beach theme," zookeepers say.

The Buffalo Zoo has six gorillas, and throws each of them a party once a year on their birthday, said zoo keeper Hayley Thoma.

"We make it individualized and special for every one of them," she said.

Koga is the father of three gorillas at the zoo, said gorilla keeper Emily Detine.

She also said 30 is about the median age of gorillas, so Koga has plenty of time to enjoy more birthday celebrations and continue impressing visitors, such as those that came to check out his birthday party.