The president of the Rodeo Cowboys Association has compared the death of a horse during an event over the weekend to a triple fatality road crash last week - saying they were both unpredictable accidents.
A horse died at the National Rodeo Finals in North Canterbury on Saturday - it's the fourth animal to die since the season started in October.
Rodeo Cowboys Association president Lyal Cocks said the horse died during a "bronc" bareback event after the rider had finished.
"It caught its head in the fence and twisted its neck and went down, and within a few minutes the vet was there to check it - he didn't have to administer any pain killer because the horse was basically dead at that point," he said.
Mr Cocks said he suspected the horse had broken its neck and died almost instantaneously.
But he said it was still a great event and the death was an accident that was unpreventable.
"Accidents do happen. In all activities and all sports. We cannot always prevent accidents from happening," he said.
"You can't prevent accidents. Those three tourists who died in Tekapo, that was an accident too apparently."
The Ministry for Primary Industries (MPI) said it was investigating the death to determine whether there had been any breach of the Rodeo Code of Welfare or the Animal Welfare Act.
So far it has found the deaths of the three other animals killed at rodeo events this season - a horse and a bull were both put down at the Gisborne Rodeo and another horse died at the Methven rodeo - were all accidents, with no breaches.
In a statement, MPI said it was rare to have four serious incidents in one season and it was in discussions with the Rodeo Cowboys Association to see what could be done to prevent more.
But Green Party MP Gareth Hughes, who has a Member's Bill that would ban using small calves and animal wrestling, said rodeo was inherently dangerous for animals.
"I don't think it's accidental, it's inevitable ... the pain and suffering these animals are being put through," Mr Hughes said.
"If you did it to a cat or dog you'd go to jail, if you did it on a farm you'd be prosecuted, but if it's done in front of a crowd as part of entertainment it's legally allowed."
MPI said it was not a legal requirement for rodeo organisers to report animal deaths, but it looked into everyone it was made aware of to see whether there was a breach of the Rodeo Code of Welfare or the Animal Welfare Act.
Marianne Macdonald, spokeswoman for the animal rights group SAFE, said that meant there may have been more deaths during this past season than those officially reported.
"This season there have been four deaths of animals in the rodeo ring but we don't know how many others this season and previous seasons are actually being killed and injured in the training events, where there's not so many people watching," she said.