Its Facebook page reads: "When New Zealand rugby players have free time in South Africa, see what they get up to. Here are the Crusaders rugby players killing wildlife for laughs on a recent visit to South Africa."
Foundation director Dr Bool Smuts told the Herald the Crusaders' kills would have taken place on a private game farm but it was "exceedingly unlikely" the players consumed their hunt.
"This was not hunting for the pot - this was hunting for the joy of killing the animal," he said.
"We accept it was legal ... The question we are asking is to what value is it for conservation and is it an ethical practice for status symbols in society to be partaking in."
Sam Whitelock told TV3 he didn't eat the zebra, but others on the trip did. "On the farm that we were on, the workers ate all the meat. [We] made sure we didn't shoot something for fun because that's not what we are about and it's something I feel very strongly about."
The Crusader said he grew up hunting with his brothers on a family farm.
Asked if the shoot in South Africa was a bad look, he said it was best to "be careful what you do in your private time".
Crusaders chief executive Hamish Riach said the players had engaged in a "perfectly legal activity" with a licensed guide.
He said hunting bans would not be imposed on players on future visits to South Africa because the Crusaders couldn't dictate to grown men what was morally right or wrong.
"They weren't poaching, they [the animals] weren't endangered species, they didn't have an illegal guide. It was all very, very appropriate and done within the context of the legal industry in South Africa."
A New Zealand Rugby spokesman said the issue was with the Crusaders and the national body would not comment on the matter.
The International Fund for Animal Welfare, which campaigns for an end to trophy-hunting, said the pictures had been overwhelmingly condemned on social media.
Oceania regional director Isabel McCrea said trophy-hunting was a "brutal business often dressed up as third-rate conservation".
"What's worse is that the Crusaders are privileged to be role models to many, especially to young people, which is why it's so disappointing that the message this behaviour sends is that it's okay to subject animals to cruel and painful deaths for pleasure."
New Zealand Deerstalkers Association vice president Graeme Steans said there was little difference between the Crusaders hunting in South Africa and visitors who came to this country to stalk the likes of deer, thar and chamois.
The private game parks in South Africa were set up for hunting, he said.
"I'm sure there's an awful lot of New Zealanders who would like the same opportunity."
