Just a rhino and his keyboard! 

This Denver Zoo favorite really "Rhi-knows" how to celebrate! Bandhu, the greater one-horned rhino who calls the zoo home, recently turned 12 and put on an adorable concert for his keepers and online fans. 

"Happy Birthday, Bandhu! Our resident male greater one-horned rhino turns 12 today!" the Zoo wrote on its Facebook page on May 18. "It might be his birthday, but Bandhu wanted to treat you all to a special song he wrote all by himself. Using his prehensile lip to compose a tune is just one of the many ways we can use enrichment to mentally and physically stimulate the birthday boy."

Bandhu really is ready to form a band! Check out his adorable tune below:

It's also been a big month for birthdays at the Zoo across all inhabitants. On May 17, lion brothers Bahati, Usiku, Jasiri, and Kito all turned 6 years old. 

"While pop culture might promote the story of the lone male, closely related male lions will often form coalitions which give them an advantage overhunting, surviving, and even wooing the ladies whom they’ll join as a collective group! For us, that means managing these majestic littermates together and watching them grow up into the most handsome lion boys," said the zoo. 

Kim the Harbor Seal celebrated her birthday on May 15, and double-wattled cassowary Salem celebrated his 26th birthday on the same day! 

Zebra Kylo celebrated his 1st birthday on May 13. Check out his celebration video here. Kesi, a mandrill, turned 2 on May 12. Przewalski's stallion, Bataar, also celebrated his special day early in the month, as did hyena, Ngozi, who turned 22. 

Beautiful tiger, Yuri, also celebrated his birthday this month.

In addition, the new zoo tenant, Mbeli turned 19 on May 27! 

"Mbeli turns 19 today! At 19, Mbeli is the eldest of our three new gorilla boys, but he's also our quietest, and most thoughtful gorilla, as you can see by his low-key birthday celebration. His keepers say he's a leisurely mover, taking his time as he shifts from one area to another. Some of the things he loves the most are a good nest (built for him by keepers), his outdoor habitat, bringing in plants from the outdoors, romaine lettuce, and nuts he can crack with his teeth!" said the zoo. 

Happy birthday to all these amazing animals! Send your good wishes to all our furry friends in the comments.