Rockhopper penguin

The rockhopper penguins are three closely related taxa of crested penguins that have been traditionally treated as a single species and are sometimes split into three species.

Not all experts agree on the classification of these penguins. Some consider all three to be distinct species, while others separate the western and eastern forms as the southern rockhopper penguin and regard the northern rockhopper as a separate species. Still, some experts view all three as varieties of a single species.