Maritime New Zealand says it has done everything it can to find out what happened to missing sailor Paul van Rensburg but his fate may never be known.
South African Paul van Rensburg left Tauranga with his dog Juanita on 12 March to sail to Gisborne, where he was due to start a new job, on a voyage expected to last three days.
The 11-metre Tafadzwa was spotted on 28 March, drifting 60 nautical miles west of the Chatham Islands, by an Air Force Orion on a training flight. Only the missing man's dog was on board.
A search operation had been called ten days earlier after an aerial sweep covering nearly 330,000 square kilometres of ocean.
Maritime New Zealand spokesperson Sophie Hazelhurst says there was such limited information that despite extensive investigations there are no further clues as to what happened.
Family says farewell
The family of missing sailor Paul van Rensburg has given up hope of finding him alive.
In a statement, Mr van Rensburg's parents, brother, sister and partner said they had just returned from a journey around the East Cape to say their farewells.
The family is grateful to everyone who supported the "Let's Find Paul" website and held hope until the end.
Maritime New Zealand says its inquiry is closed but it will assist police investigating Mr van Rensburg's disappearance.
