Why were African Penguins previously called Jackass Penguins?

The African Penguin used to be called the Jackass Penguin.  A strange name for a penguin.  But how did it get that name? It is because the African Penguin's call sounds like a braying donkey.  Right, so now we have established that they sound like a donkey, but why were they called Jackass?  Donkey's are also called Asses (the scientific name is Equus africanus Asinus) while a male donkey is called a Jack.  Hence Jackass.  Check out this video by Hanging Out With Ryan of the penguins braying at SAMREC and tell me that doesn't sound like a donkey.