Marley was last seen in Opawa about 2.30pm on 26 September, but his vehicle was found in Sumner.
Detective Sergeant Lucy Aldridge said the Scarborough whitewash area was searched on Saturday, with efforts moving to the surrounding bays.
"Today our search efforts are focused on the surrounding bays and involves using drones, as well as boats and land teams to cover as much ground as possible."
Police, Land Search and Rescue, Coastguard Sumner, Fire and Emergency New Zealand, Surf Lifesaving New Zealand and volunteers are all helping with the search.
"We are urging anyone in Sumner and Scarborough with CCTV or doorbell cameras on their property to check their cameras from 2:45pm on Friday," Aldridge said.
Marley is thought to be wearing black track pants and a dark-coloured hooded jersey.
Police said to call 111 - quoting the reference number 250927/3331 - if Marley is sighted.
