Close to 1500 greyhounds have been euthanised over recent racing seasons – but a lack of record-keeping means the true number is unknown.
That is the finding of a damning new report on welfare in the greyhound racing industry, which has been called "disturbing and deeply disappointing" by Racing Minister Winston Peters, and "sobering" by the Minister responsible for Animal Welfare Meka Whaitiri.
The Green Party has suggested the industry should be banned, unless immediate improvements are made.
Rodney Hansen QC wrote the 93-page report after being tasked by the NZ Racing Board to look at the industry and any associated welfare issues.
He concluded that since a 2013 inquiry on greyhound racing industry there had been some improvements, but serious problems remain.
That included the tracking of greyhounds that do not race or retire from racing.
"There has been a modest increase in the availability of racing opportunities and of levels of rehoming. However, gains have been insufficient to right the structural imbalance," Hansen wrote.
"There have been significant advances in track safety, leading to a material reduction in injuries and deaths from injury while racing. However, the numbers of injuries at the first turn remains high and efforts must continue to find ways of preventing the convergence of 'bunching', which is the major cause of serious injury and death."
Hansen found recommendations after the 2013 inquiry to reduce the number of greyhounds euthanised after being retired from racing had not worked.
"The number of greyhounds reported as euthanised continues at high levels with evidence of widespread non-compliance with reporting requirements strongly suggesting the true figure is much higher."
Hansen's report found the number of greyhounds deregistered as a result of being euthanised over the 2013/14 to 2016/17 seasons totalled 1447. The average age was 3.6 years.
There was no evidence of the prohibited practice of "livebaiting", which is the use of an animal, dead or alive, in training. However, Hansen noted an investigation was under way.
Peters said the report had revealed rates of dog euthanasia and "unaccounted" for animals that were "simply unacceptable".
"It is not tolerable having some owners giving the rest a bad name," Peters said, adding he had held recent meetings and the industry "was left in no doubt just what dismal view the government has of this".
The greyhound industry had advised it has initiated a work programme and will implement most, if not all, of the recommendations in the Hansen report.
"Serious improvement is required particularly on kennel inspections, dog tracking, approvals regime before a dog can be euthanised, track safety, dog rehoming and stricter enforcement of the dog health and welfare standards," Peters said.
Whaitiri said the report was sobering reading, and she had asked the National Animal Welfare Advisory Committee to report to her regularly on the progress made by industry.
Green Party animal welfare spokesman Gareth Hughes said immediate action was needed.
"Only eight other countries in the world have commercial greyhound racing industries and this damning report raises the question if in fact it should be reduced to seven.
"Greyhounds shouldn't be dying for people's gambling and viewing pleasure."