The girl's mother did not want to talk about the attack yesterday.
Whangarei District Council spokeswoman Rachel Pascoe said the dog's owners were co-operative and it was likely the dog would be surrendered and destroyed.
The dog's owner, Aaron Sadler, said he was not home at the time of the attack but had been told his pet, a male staffordshire terrier/cross had been guarding its food.
"He's a good dog. I've kept it since he was a puppy and I'd like to keep him,'' Mr Sadler said.
The attack is one of four on children in the past week.
A 3-year-old boy was left with critical injuries after he was bitten in the throat by a doberman-Staffordshire-pitbull cross in Ashburton.
An 18-month-old girl received significant injuries to her face and stomach after being attacked at her Porirua home by a pitbull-Staffordshire and a 9-year-old girl received deep cuts to her head and arm after being attacked by an American bulldog in Rotorua.
The Government has promised a review of dog control laws to see if there is anything else that can be done to prevent serious attacks but has warned there are "no magic bullets'