According to zoo tradition, each of the babies has to be given a name starting with the letter E and the names should come from the bible.
The babies were 5cm long when they were born on 9 April. They are the fifth litter for parents Azaria and Adam.
They have survived despite threats from predators, such as seagulls and foxes.
"They are really strong, feisty little creatures, and the rest of the group works well to look after them," said a zoo spokesman.
"Our only problem now is finding names for them all."
Staff are keen to hear from visitors who can come up with suitable names for the litter.