"The shark was dead. The guy that caught it, he fought it for 10 hours. It died while he was catching it. It's not like it was an intentional killing.
"We are against any sort of killing of animals that don't need to be killed."
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The day before the video was uploaded to Facebook, a photograph of a large thresher shark being weighed outside the Tauranga Game Fishing Club was uploaded on Mr Collins' page. Accompanying words said: "289kg thresher after 10-hour battle to the death".
Auckland environmentalist Catherine Cassidy contacted the Bay of Plenty Times in disgust at the video, which she said was brought to her attention by a shark expert in Borneo. She also contacted the Ministry of Agriculture and Fisheries (MAF) and questioned what rules were in place at game fishing clubs that allowed "this kind of fishing".
MAF confirmed it was investigating the incident. "We are making an assessment and will then determine an appropriate course of action. MAF always encourages members of the community to report any concerns they have about animal ill treatment or cruelty."
Ms Cassidy, a zoologist, said the video clearly showed the men claiming the "fun" of shark surfing. She said the act was "a shockingly disrespectful attitude to have to some of the rare marine animals in the world".
"We see people working hard worldwide to establish shark sanctuaries, where every shark counts, and then we see acts like this from a so-called developed country. It is heartbreaking and offensive."
Among the feedback Ms Cassidy received was that the behaviour was an act of harmless fun and she should put it in perspective. "It's not harmless fun. It was cruel and disrespectful. Respect for the oceans and marine life begins at home. People wouldn't tie a slaughtered cow to the back of a van and drive it through a street, would they?"
A spokeswoman for Tauranga Game Fishing Club said the club did not wish to comment. "We do not wish to be involved," she said.
President of the New Zealand Sport Fishing Council, Mark Connor, said the actions of the men involved were "very disappointing".
"We have a game fishing code of standards and we try to do everything we can as humanely as possible and this certainly sits outside our standards," he said. "It doesn't sound like a legal issue but we do not condone this type of behaviour at all and we would be very disappointed if it was one of our members or someone associated with the club. It's disappointing. People like this can give us a bad name because we try to do things as correctly as we can, both morally correct and legally correct."
Mr Connor said sharks were sometimes dragged backward behind a boat as they could be hard to kill and tough to get inside the boat.
"But surfing on a shark is certainly not acceptable."
Department of Conservation marine scientist and shark expert Clinton Duffy had been made aware of the incident, despite being on leave.
He was contacted by someone from the White Shark Conservation Trust and asked whether the department could do something about it. Mr Duffy identified the shark as a bigeye thresher. He said the species had a major decline in numbers in the north Atlantic and north Pacific Oceans but was not significantly affected in New Zealand waters.
"I don't know about the wisdom of shark surfing but the shark itself is fairly common."
A local fishing expert said the behaviour of the men involved was "pathetic" and "stupid".
Brett Keller, owner of Tauranga Marine Charters, said the men involved were "a couple of fools."
"What would have happened if it had taken a leg off? Then they wouldn't be going on about it and getting attention," he said. "I'm not a big fan of catching sharks, I prefer to see them swimming around and if I catch something, I like to eat it. Those thresher sharks are pretty harmless, not if you're a fish, but they're harmless to humans. These guys are putting on a show for their 15 seconds of fame, showing they're macho, bravado, and I think it's pretty pathetic really."
Tauranga SPCA animal welfare inspector, Jason Blair, said it wasn't likely the actions breached any laws but the SPCA "frowned upon" mistreatment of animals, dead or alive. National MP Simon Bridges said the men could have breached animal welfare laws if there was cruelty against the animal when it was alive.
The video had been removed from Facebook.
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