Newshub has information that some fishing boats have been illegally dumping their entire haul, and the evidence comes from a surprising source -- the Ministry for Primary Industry's (MPI) own investigators.
The information is contained in two reports, which MPI is accused of trying to keep covered up.
One of the preliminary reports is called Operation Achilles. It was written by a senior MPI investigator and details what it describes as "serious", widespread offending in the South Island.
The operation was part of a trial of CCTV cameras onboard the boats, and it found four of the five vessels equipped with the technology "openly discarded substantial quantities of quota fish" without reporting it.
What is of particular concern, though, is that the report states that between 20 percent and 100 percent of some quota fish were being discarded every time the net was pulled up.
MPI has always maintained that it doesn't think dumping is a major problem -- but that seems to be completely at odds with its own report.
Photos show Kiwi fishermen throwing valuable species overboard. The waste includes kingfish, which are not recorded.
Small or damaged elephant fish and gurnard also go over the side -- all of which is illegal according to the ministry's own report -- a report they decided not to release publicly.
MPI deputy director general Scott Gallacher says it is "absolutely not" a cover-up.
"There's been no cover-up here," says Minister for Primary Industries Nathan Guy. "These are internal, draft investigations, part of which has been unfortunately leaked."
The report was part of an operation to see how hectors dolphins were being caught in trawl nets in the South Island.
Senior MPI investigators not only noted two dolphins being caught, they found widespread illegal fish dumping.
But it wasn't just one rogue operator. Estimates in the report say 20 percent to 100 percent of some quota species were being discarded every time the net came on four of the five vessels they were monitoring.
"Clearly it's a concern when you look at what the investigators were getting at that stage of the investigation," says Mr Gallacher.
"What's amazing about this report is it shows that it's across multiple vessels where dumping of large qualities -- a quarter to a third of some quota species -- is being dumped off the boat routinely," says Greenpeace NZ executive director Russel Norman.
But MPI says some of what was seen by its own investigators -- even though it was also captured on video -- was "misinterpreted".
"It highlighted that there were some misinterpretations or misunderstandings of some aspects of what we were dealing with," says Mr Gallacher.
But then there's another report, Operation Hippocamp. It inspected seven vessels in the southeastern trawl fishery and found "between one third to two thirds of Gurnard may be dumped by inshore trawlers". MPI has video footage, but won't release it.
"MPI must release the video that they are sitting on," says Dr Norman. "People in New Zealand have a right to see it."
No one was ever prosecuted over the dumping. MPI says that's because it got legal advice the footage couldn't be used in court.
Do you have more information? Contact MichaelMorrah@mediaworks.co.nz.