Experts in searching waterways are joining the search for a Dunedin man missing for six days.
Police and 31 search and rescue volunteers, using dogs and a helicopter, are looking for Stephen Lowe, who disappeared last week.
He left work on Portsmouth Drive in Dunedin around 10am on Friday, police said. His car was found on Monday near McLeans Falls in the Catlins Conservation Park in South Otago.
Senior Sergeant Cynthia Fairley said there had been no other sign of Mr Lowe since and they feared for his welfare.
"We're very concerned, and we're very realistic in what the outcome may be. We've been trying to support the family through this, because this is a really difficult and tragic time for them, but we'll work on it today with some hope and we'll hopefully be able to have a better ending to the day."
Senior Sergeant Fairley said swiftwater search experts were joining the search today.
The aerial search was limited due to the dense native bush in the area.
Police were also hoping to hear from "Mike and Talia", who may be from the Dunedin area, and who had been tramping in the McLean Falls area over the weekend.