A search has been under way to find an expensive high-tech monitoring buoy and mooring which vanished from the edge of the Kāpiti Marine Reserve.
The buoy and mooring, worth about half a million dollars, was positioned in late November and has provided real-time measurements on currents and waves, salinity, oxygen and chlorophyll, water temperature, sediment, wind direction and speed.
But on Sunday, March 28 at 1.10pm the buoy stopped transmitting data.
The buoy had been programmed to 'phone home' if it drifted from its mooring or suffered damage, but no alerts at the time, or since, had been received.
Department of Conservation (DoC) principal marine science adviser Dr Megan Oliver said the disappearance had been a "complete mystery", especially considering how robust it was.
But a search conducted on Thursday provided a glimmer of hope.
"We had mixed success.
"We got some images back of something lying on the seabed, the dimensions of which would fit with the mooring.
"But we need to go back.
"We did have a cable problem with one of the cameras which meant we didn't get very good pictures.
"But we did get some images back that would indicate there is something there at the mooring site.
"This week we are working to source another camera, ideally one with a little arm on it, so that if we go down we can take a rope and look to hook the mooring and bring it up."
Dr Oliver said there was always a high risk when putting something into the ocean but "this was in a near coastal area, it's not the open ocean, and of course we wouldn't have expected this to happen".
"The community has been great including the Guardians of Kāpiti Marine Reserve.
"The word has gone out and people are being as helpful as they can around providing information or support which is really encouraging."
The buoy was a 'sister' to the one in Wellington Harbour.
The Kāpiti buoy project was a joint venture between NIWA, the Greater Wellington Regional Council, and DoC, and was partially supported through Air New Zealand's support of the Marine Sentinel Sites Programme.