Two biosecurity dogs were also dispatched to the island early in the search but have not been able to confirm the stoats' presence.
Auckland Council's incident controller, Jonathan Miles, said, "While this is good news and a relief, it's a stark reminder to locals and visitors to the island of the importance of checking gear and goods on their boats and in their cars for stowaways before heading into the gulf".
"Great Barrier Island has never had the same pests as the mainland – that is, possums, stoats, Norway rats and hedgehogs.
"As a result, the island's unique local flora and fauna have flourished and survived whereas it has disappeared from the mainland," Miles said.
"Stoats are a serious threat and any incursion, while always a possibility, would be devastating to the island's native bird life. Vigilance is key to keeping our islands pest free."
To date, around $9000 - excluding staff time - was spent on the hunt; however, if a presence were to be found the cost to eradicate would be much higher, Auckland Council said.
Tracking will continue for the next three weeks and if no stoats are detected a review of the operation will be made to determine whether to continue.
Residents and visitors are urged to contact Auckland Council's biosecurity team on 09 301 0101 if they genuinely believe they have seen a stoat.