We spent three years interviewing 160 Bigfoot hunters

Be it a hoax or an undiscovered species, the mystery and mythology around Bigfoot has captured people's imaginations for decades.

Widely regarded as a cultural icon, Bigfoot was catapulted into the public sphere in 1967 when grainy footage was captured of a 7ft tall, ape-like figure walking upright and glancing back at the camera in the US state of California.

But concrete evidence is contested and the debate over its existence has raged for nearly 60 years, with naturalist Sir David Attenborough supporting the possibility of a Yeti, Bigfoot or Abominable Snowman, while other researchers remain sceptical.

To understand the fascination, two sociologists spoke to more than 160 "Bigfooters" who are serious about collecting evidence that the beast is real.

"Bigfoot exists - at least as a known object that people shape their lives around," said Dr Jamie Lewis, sociologist at Cardiff University.

"One thing I would never do is question the dedication of a fair percentage of the Bigfooters."

Along with Dr Andrew Bartlett form the University of Sheffield, Lewis spent three years interviewing believers, academics and sceptics for their recent book Bigfooters and Scientific Inquiry.

Researchers spend "days, weeks, in some cases months" in the dense forestry of North America, says Lewis, "with many spurred on by childhood encounters or brought into the pursuit by someone close to them".

"We're talking in the thousands of people. But there are a couple of hundred really serious people of which I probably interviewed at least half," said Lewis.

Embarking on expeditions in vast and sometimes dangerous environments, Bigfoot hunters set out with drones, infrared cameras, audio recorders and materials to cast footprints.

They also try to imitate Bigfoot "calls" as there is the belief Bigfoot can communicate through howl-like sounds or by knocking on trees.

Bigfooters are mostly middle-aged white men, often ex-military, and based in rural areas with blue collar jobs, said Lewis, adding there was a "masculine energy" and a "frontier" mentality to the community.

"A lot of it is kind of an attempt to re-enchant the world, so to speak.

"The idea that an eight foot ape is still living in the US not known to science is quite an enchanting idea."

Bigfoot has been the focus of multiple documentaries and it's thought there are thousands who believe in the creature's existence, with nearly a quarter of Americans believing Bigfoot is either probably or definitely real, according to a YouGov survey from 2021.

Believers can be divided into two groups, Lewis said.

Apers believe Bigfoot is just a primate unknown to science while Woo-Woos think Bigfoot is some sort of inter-dimensional traveller - an alien of sort.

Their study focused on interviewing Apers who "aren't anti-science but they are counter elitist and counter-establishment".

Bigfooters have even made their own DNA kits to test hair samples they find but have also gathered evidence which cannot be accounted for, said Bartlett.

This ranges from shapes captured on trails or infrared cameras to a howl or witness testimony, allowing Bigfooters to hypothesise what that means about the beast's "anatomy, behaviour, sociality and levels of intelligence".

Glenn Adkins, 59, from Ohio, USA - which ranks fourth in the World for Bigfoot sightings - has been investigating Bigfoot for more than 30 years

H has lived through the shift in attitude towards Bigfoot hunting as he recalled being ridiculed for his fascination with Bigfoot, which began when he was about nine.

He said he first came face-to-face with a Bigfoot while camping out with a friend in 1992.

"It was standing right there and looking at us... we both froze of course.

"The last thing on my mind was getting a picture, you are all of a sudden in the presence of something that is awesome. You can't fathom how big they are."

Glenn said the primate was 7-8ft (2.1-2.4m) tall and looked very heavy.

"When it took a deep breath I could see it almost pull up and take that breath and I'm like 'oh my God, he's going to suck all the air out of this place and I'm not going to have any'."

"It was just that big and that impressive."

Glenn said the encounter lasted no more than 10 seconds but it felt like it lasted much longer and he "didn't know what to do".

In the years since, Glenn said he had spotted various signs of Bigfoot, through unidentified faeces, hoots and animal remains torn apart in ways which would require extreme strength.

March was an "exciting time" as Glenn was on the ground with the Bigfoot Society, following reports of a "surge" of clustered sightings in north-east Ohio in the space of one week.

Glenn hopes to edge closer to developments in the field but despite years of scaling mountains, he believes "you don't find Bigfoot, Bigfoot finds you".

He said even if evidence revealed Bigfoot doesn't exist or it was a hoax, he would not see it as time wasted as he had seen the most wondrous things in the woods, but would like to see people being more open minded about the mystery.

"People like to make fun of things they don't know."

Speaking in a Nature on PBS documentary, Sir David Attenborough spoke of a huge ape that existed between six and five million years ago, the gigantopithecus.

Described by some as the largest ape to have ever existed, it inhabited grassland in southern China, according to studies, and "could well have stood at three metres tall, in which case it would have been eight times as heavy as I am," said Attenborough.

"And if you're as heavy as that, you don't spend much time climbing in trees because they won't support you.

"So the likelihood is that his arms are quite short, and he walked upright."

The Bigfoot Field Research Organization (BRFO) has more than 5,000 reports of sightings on its online database.

Often regarded as the Bigfoot capital of the World, Washington state boasts 730 sightings recorded on BRFO, but Bigfooting is not exclusive to northern America, and there are researchers in Australia and even the UK.

Bartlett said Bigfooters "are quite open to the idea that a lot of these sightings are misidentification".

"It can be people being spooked by a bear or a moose as they are just not familiar with the woods.

"They are aware are people spoiling the well, so to speak, with hoaxes and frauds - manufacturing footprints."

Their research is at risk from those trying to get a "quick hit" online, said Bartlett, while there are others who create evidence to trick Bigfooters.

Lewis admitted some of the witness stories were compelling and "would have an effect" on him as he pondered them before his rational self took over.

Describing himself as a "romantic sceptic", Lewis said a lot of the people he spoke to "were remarkably articulate".

"An interview wasn't completely illogical, some of it was logical... their dedication came across.

"There were certainly some of them who were open to the idea Bigfoot doesn't exist, but just wanted science to take them seriously.

"I found the qualifying work they did in positioning themselves as a believer, but a serious believer, quite compelling.

"And that to me was one of the more convincing aspects of listening to people."