(CNN)Happy birthday, Toshi!
An endangered rhinoceros at a Miami, Florida, zoo turned 43 and is now the oldest male black rhino in the United States.
To celebrate Toshi's milestone, Zoo Miami staffers and volunteers made him a heart-shaped cake, frozen ice blocks with his name and sang together "Happy Birthday."
Toshi was born in Hiroshima, Japan, in 1977 and moved to Miami in 1983 as part of a breeding recommendation, according to Zoo Miami.
He produced at least five offspring over the years but he's now enjoying retirement and some good back scratches from staffers at an off-exhibit area of the zoo.
Toshi is a really a senior citizen of the zoo. The life span of black rhinos ranges from 35 to 40 years, according to the African Wildfire Foundation.
These rhinos are considered critically endangered. There are only about 5,000 black rhinos, the smaller of the two African rhino species, in the world, according to the World Wildlife Foundation.