Tonkins punched it in an attempt to save his dog, and the footage went viral at when it was recently posted to Facebook.
Daily Mail Australia then revealed Tonkins was a zookeeper at Taronga, which on Tuesday announced he could keep his job.
"Following the events of the last 48 hours in which Greig Tonkins was seen on social media punching a kangaroo in attempt to free his dog from its hold, Taronga has been inundated with concern for Mr Tonkins as well as enquiries regarding Taronga's position on the events," the zoo said.
"Best practice animal welfare and the protection of Australian wildlife are of the utmost importance to Taronga.
"Taronga strongly opposes the striking of animals and does not support the practice of using dogs to hunt, as this can result in negative welfare for both species.
"Mr Tonkins is an experienced zookeeper and during his six years at Taronga has always followed Taronga's best practice approach to animal care and welfare. We confirm that there is no suggestion of Mr Tonkins' employment ending as a result of this event.
"However, the highest standards of animal welfare and care are a core value of Taronga and one that we expect our staff to uphold in all their interactions with wildlife and we continue to work with Mr Tonkins on his conduct in regards to this incident."
The father-of-two had gone on the hunting trip in an effort to help his sick friend Kailem Barwick catch a "tonner" - a wild boar that weighs more than 100kg.
Best practice animal welfare and the protection of Australian wildlife are of the utmost importance to Taronga and we do...
A videographer joined the group to record their special trip for Kailem, who has died, and recorded the moment that has now gone viral.
Speaking to Daily Mail Australia, one of the men on the trip backed Tonkins' actions, saying the punch was only thrown to protect the dog and prevent the 'roo attacking anyone else.
"The dog wanted no part of it, all it was trying to do was escape from the 'roo and that's why he stepped in," the man said.
"There's people on social media saying, 'I know men like that, I bet they killed it afterwards', but that's just ridiculous.
"He only threw the punch to redirect the animal and afterwards there were a few nervous and relieved laughs, and then we just went on with getting Kailem a tonner."
The trip ultimately proved successful, and the group ensured the young man managed to kill his "tonner".
Sadly Kailem died last week after a long cancer battle, and his funeral was to be held tomorrow.
Greig Tonkins is an elephant keeper at Taronga Western Plains Zoo. Photo / Facebook
The fellow hunter said he was dumbfounded by the reaction and left wondering why some were happy for the dog to be injured but not the kangaroo.
"The video went viral in America and there was not one bad comment, and then it goes crazy in Australia and there's a whole bunch of outrage," he said.
"It made me sick to be part of this country when people were wishing this family man and dog died, when the kangaroo wasn't even hurt."
Daily Mail Australia can also reveal Tonkins is a committee member of the Australian Pig Doggers and Hunters Association.
In October, Max, the specially trained dog that was attacked by the 'roo, won a high jumping competition at the organisation's AGM. The performance was captured on video.
