After a three-day hunt, Knowlton, 36, shot the rhino using a high-powered rifle in the company of government officials to ensure he killed the right animal.

Knowlton has been heavily criticized and even received death threats after he won the right to shoot the rhino during an auction held in Dallas in 2014, reported AFP News.

“The whole world knows about this hunt and I think it’s extremely important that people know it’s going down the right way, in the most scientific way that it can possibly happen,” Knowlton told CNN camera crew whom he asked to join him in the hunt.

“I think people have a problem just with the fact that I like to hunt… I want to see the black rhino as abundant as it can be. I believe in the survival of the species.”

Knowlton targeted an old rhino since the older ones can no longer breed and are believed to pose a threat to the younger ones.

“I felt like from day one it was something benefiting the black rhino,” said Knowlton after the hunt.

“Being on this hunt, with the amount of criticism it brought and the amount of praise it brought from both sides, I don’t think it could have brought more awareness to the black rhino.”

According to the International Union for Conservation of Nature (IUCN), an estimated 2,400 rhinos have been poached across Africa since 2006 and if the trend continues, the endangered species’ population can fast start to decline.

“Well-organised and well-funded crime syndicates are continuing to feed the growing black market with rhino horn,” said Mike Knight, Chairman of the IUCN SSC African Rhino Specialist Group.

“Over the past few years, consumer use of rhino horn has shifted from traditional Asian medicine practices to new uses, such as to convey status. High levels of consumption – especially the escalating demand in Vietnam – threaten to soon reverse the considerable conservation gains achieved over the last two decades.”