(CNN) - The Milwaukee County Zoo is sad to announce the passing of a longtime resident. Patti, the oldest living hippopotamus at an accredited zoo in the United States, has died. Patti had marked ...

(CNN) - The Milwaukee County Zoo is sad to announce the passing of a longtime resident. Patti, the oldest living hippopotamus at an accredited zoo in the United States, has died. Patti had marked her ...

A river hippopotamus at the Milwaukee County Zoo was humanely euthanized on Sunday, Nov. 10. Patti marked her 55th birthday in February. She was born at the Dallas Zoo and arrived in Milwaukee in ...