A private man he may be, but Palmer's life is surprisingly well documented on the internet, adding more fuel for the fire. Hunter Walter James Palmer, left, with another lion he killed. Credit:Facebook In the competitive world of hunting, exploits are routinely chronicled on specialist websites, such as Safari Club International, where Palmer's profile lists 43 kills including caribou, deer, buffalo, moose and a polar bear. He was convicted in 2008 in relation to the poaching of a black bear in Wisconsin in 2006. In 2003 he was fined for fishing without a licence, and in 2009 he paid $US127,500 in a settlement to a receptionist he allegedly sexually harassed, without admitting guilt.

The dentist has issued a statement of regret for killing a lion that was so well-known and part of a study. Cecil strolls around in Hwange National Park in Zimbabwe. Credit:AP/Paula French He said he relied on his local professional guides to whom he reportedly paid $US50,000 ($68,000) to ensure that the hunt was legal, and that he will co-operate with any inquiries by the US or Zimbabwean authorities, which had yet to contact him. "Again, I deeply regret that my pursuit of an activity I love and practice responsibly and legally resulted in the taking of this lion," Palmer added. Walter Palmer with a California bighorn. Credit:Trophy Hunt America

But on social media there was no mercy. Celebrity Sharon Osbourne posted a series of tweets. Walter Palmer with a Roosevelt elk in his quest to "harvest" every species of North Americian big game. Credit:Trophy Hunt America

Caroline D of Los Angeles wrote: "I'm glad you'll get to remember Cecil the Lion for the rest of your life, not because of his head hanging in your living room, but because from this day, your dental practice is ruined. I doubt you'll have the means to drop another 50k to bribe some desperate game reserve guards anytime soon. Best of luck finding clients." Palmer has been all but silent. Apart from the statement issued through a public relations firm, he told the Minnesota Star Tribune: "obviously, some things are being misreported". Walter Palmer with a leopard shot in Zimbabwe. Credit:Trophy Hunt America

His dental practice was closed on Tuesday, apparently hastily, and a note on the door referred visitors to a public relations firm. The practice's website and Facebook page were taken down. Door-knocking reporters at the Palmer family home received no answer. While the dentist's true feelings about the incident, about being described as "the most hated man on the internet" and the likely effect on his life can only be the subject of speculation, research into the growing phenomena of public shaming offers a few clues. For his book So You've Been Publicly Shamed, Jon Ronson spent two years interviewing "everyday" people who had been pilloried on social media. He found they "were mostly unemployed, fired for their transgressions, and they seemed broken somehow - deeply confused and traumatized".

One was Justine Sacco, a New York publicist who tweeted before getting on a flight from London to Cape Town in 2013: "Going to Africa. Hope I don't get Aids. Just kidding. I'm white!". By the time she got off the flight 11 hours later, her Twitter feed had become "a horror show" of "ideological crusade against her perceived bigotry" Ronson writes. Sacco's employer was among her condemners, and she lost her job soon afterwards. She told him it was "incredibly traumatic" and "I cried out my body weight in the first 24 hours". She was told no one could guarantee her safety and workers threatened to boycott hotels where she was booked to stay.

"All of a sudden you don't know what you're supposed to do," she said. "If I don't start making steps to reclaim my identity and remind myself of who I am on a daily basis, then I might lose myself." Some people feel an "extreme need to hide, run, escape and avoid", said Lydia Woodyatt, a psychology lecturer at Flinders University who studies shame and self-forgiveness. "For others, [shaming] can lead to extreme anger, defensiveness and self-protection [behaviour]." She said people who were best able to repair their lives were those who could admit wrongdoing, take responsibility, reaffirm their values and move on. But Dr Woodyatt questioned whether this was possible in the face of online shaming which "blows it out of all proportion".

"How do you take responsibility properly and repair when the whole world has an image of you doing something wrong?" Writer and social commentator Clementine Ford, who was the subject of a social media storm recently when she posted a semi-nude photo on Twitter in protest at the breakfast program Sunrise's attitude towards victims of nude photo hackings, said the feeling was "initially overwhelming" because it was unexpected. "It just spread so rapidly that you suddenly end up feeling incredibly exposed and available to peoples' comments". While she engaged professionally in the social media world by choice, she said: "I can imagine for ordinary people it would seem suddenly quite bizarre and disassociative". Ford said the dentist "will absolutely be receiving death threats right now, and that is terrible".

She said Palmer needed to reflect on his behaviour, but so should the people condemning him. "It is OK to get angry on social media, and OK to express disappointment, but it is not OK when you start saying things that you would not say to someone's face." In April, Ricky Gervais led a shaming campaign on Twitter against giraffe killer Rebecca Francis, who shares her penchant for killing wild animals on her Facebook page.