Five Norwegian men who shot New Zealand wildlife were today ducking for cover as a row continued over their YouTube video of protected kereru being slaughtered.

The men last night stripped the clips from the internet as the controversy spread to their homeland.

But other copies of the clip are still attracting a torrent of condemnation, and now authorities in the men's home country are talking about the potential for them to be prosecuted for killing endangered wildlife while overseas.

The Norwegians spent the New Zealand summer travelling around trout streams and hunting, then returned home to post a video compilation of their trip's highlights, apparently with hopes to return and make a longer video on fly fishing in the South Island.

But after three days their clip of a rifleman shooting at a kereru, the bird falling from a tree, and film of one of the tourists holding two dead, bloody birds had attracted over 400 scathing comments, with significant criticism from other Norwegians shamed by their behaviour.

Department of Conservation spokesman Reuben Williams said the kereru was an absolutely protected species under the Wildlife Act.

The maximum penalty for killing such protected wildlife is a $100,000 fine and up to a year in jail.

Conservation Minister Kate Wilkinson said she was "absolutely outraged" by the clip, which also showed the tourists shooting a paradise shelduck.

Paradise ducks can only legally be hunted with licence and a shotgun during the shooting season starting in May. Illegal hunting can bring a fine of up to $5000.

The YouTube video also had footage of a Fox Glacier helicopter pilot carrying the men on a West Coast hunting trip, where they shot tahr.

Wildlife enforcement officials are understood to have sought from the helicopter company and the pilot information to identify the men.

On the east coast of the South Island they shot wallabies and a hare.

Hans Tore Hoviskeland, a senior public prosecutor at the Norwegian National Authority for Investigation and Prosecution of Economic and Environmental Crime (Okokrim) told the nation's biggest newspaper, Aftenposten, that if the men had shot protected animals in New Zealand, "it is very regrettable".

"The way I see it, they can also be prosecuted in criminal proceedings in Norway," he said.

"We will do further research to see what has happened in the case".

Mr Hoviskeland said Norwegians convicted of hunting protected endangered wildlife may be liable under the Norwegian penal code to up to six years in jail.