Eketahuna fire chief Max Mayer said he was tied to a secure line and lowered about three metres down the cliff face to where the lost dog had been sheltering.
He said they had rescued a single cat in the past but it was the first time Eketahuna firefighters had rescued a dog.
He said Fergie was "very happy to see me" once he arrived at the dog's perch and the entire rescue took about ten minutes.
Mrs Barber said she was happy to be able to return Fergie to her owners.
"Fergie was apparently vomiting bile that first night [home] but was eating by the next day. I really thought Izzy was going to find a dead dog, not a live one and it was good to be able to help get the dog back to its owners."