Reducing the Interislander fleet by one could have wide-ranging implications, including on people's pockets.
Aratere will retire late this year or early next when demolition begins on its aged dock to add infrastructure for new ships.
Two new ferries aren't due until 2029.
Transporting New Zealand Chief Executive Dom Kalasih told Kerre Woodham it could affect ferry fares – with the addition of supply chain costs.
He's asking road freight supply customers to work with them as they navigate the changes.
LISTEN ABOVE

Barry Soper: Newstalk ZB Senior Political Correspondent on the five MPs allegedly involved in leaking party details, National leadership vote
08:22

Kerre Woodham: Put up or shut up and shove off
05:21

Nick Tuffley: ASB Chief Economist on the expectation household expenses will increase by $55 a week
12:34