Cryptozoologist Pat Spain travels the world to track down real-life monsters lost to science. In his new National Geographic TV series, he roams the planet’s most remote wildernesses, quizzing locals for their eyewitness accounts, interpreting folklore and analysing scientific data. It’s in his blood, after all: his great-uncle was Charles Fort, the legendary mystery hunter whose name gave rise to a new term, ‘Fortean’. He’s got a lot to live up to. As WideWorld found, Pat carries out his quest with bravery – and a tolerance to pain that you’d find hard to beat.

Beast Man is a hell of a job title, Pat. What does that involve daily?

I have a weird life – my job is an interesting one to describe. Usually I’m working at a biotech company, which is about as far from a wildlife scientist as you can get! I went to a school for marine biology originally and pursued that aspect of my life at the same time as this lab job, including work that I do in a reptile sanctuary here in New England. We’ve got everything from cobras to large lizards, alligators. People have the immediate feeling that they have to get away from reptiles, but reptiles mostly just want to stay away from you. For every snake you see, there’s 50 that you don’t!

So how did the Beast Man series come about?

It’s been my dream since I was a kid to go to these animal’s environments and make sense of it for people, to show people the reality of the animals and give them a level of excitement about them. I grew up watching David Attenborough documentaries – that’s what I wanted to be. The idea of searching for animals that people don’t know about was always an interest too. I once caught a barracuda off the coast of Maine on a research trip – nobody believed me. It was hundreds of miles from its normal range; I actually had to send it to get it positively identified by someone. There are many things that people just don’t know yet – I even once found a water moccasin snake 600 miles north of its range. The oceans are a mystery, that’s what I love about marine biology. There’s dozens of very large species out there that we really can’t find.

So have you travelled deep underwater?

Yes – that was another ultimate dream realised. I went down to 100ft in a small submersible, and it was incredible. It was everything you imagine it could be: the most alien landscape ever. You just can’t hold a candle to the strange sights you see: from weird squid to bizarre, gelatinous creatures. The thing is, when you haul them to the surface they’re just not the same, it’s not their natural environment and they look totally wrong.

How did the filming of the series work out?

We shot the Beast Man series over the course of four months, with about 15 days in each location. Planning for each episode was difficult: we were visiting some of the planet’s most remote locations. In Sumatra, for instance, we were going somewhere that was a five-day hike from the nearest road – and that was nowhere near anything anyway! I think Sumatra was probably the most hostile environment. It was very hot and wet – I got trench foot picked up a bad stomach bug… I’m confident that at once point a tiger was stalking us, too. The Sumatran wilderness is like nothing you’ve ever seen before. It’s a child’s picture of a rainforest, how you imagined it as a kid – so perfect, it’s like a movie set.

A large part of the series involves understanding the locals and finding out about what they know. How did you go about getting a good reception?

Seeing the reactions of these isolated tribes was just fascinating. I found that if you approach any culture with an open mind and respect, show people you respect them, they’re willing to share and embrace you as their own. In Brazil, the tribe we stayed with have had a hard time with outsiders, and are mostly closed off to them. I thought it would be touch to create a rapport with them, so I had to go through one of their rituals to gain respect, and to show I respected their culture.

Can you tell us what that was?

Sure – it was called ‘tucanderia’, a ritual that involved being stung by bullet ants. I started talking to the elders, saying I would like to do it, and they agreed. The young ones, they just said to me ‘there’s no way you can handle this.’ I was getting more and more nervous as the time approached – there was no way to back out, I had to go through with it. The production team let me get stung once before the ritual began, to make sure I wasn’t going to have a terrible reaction and die. Bullet ants are about 3 inches long, and look like wasps without wings. They’re commonly thought to have one of the most painful stings in the insect world. As I had that single test sting, I can tell you I agree.

So what actually happened in the ritual?

We went to the forest and collected hundreds of bullet ants. The elders then knock them out with a narcotic, and weave them into gloves made of palm fronds – a bit like big oven gloves. You slip the gloves on and wait for the ants to wake up. The pain is indescribable. I lost the ability to speak, and began to hallucinate. The first one bit me under the edge of my fingernail, and after that they all went in. There’s dancing and chanting going on, while your hands are getting covered with stings. The pain increases for about four hours, when it plateaus and stays at its maximum level for another 20 hours. I completely lost it. You’re meant to stay quiet and calm, which I managed for quite a while, but I did let one cry out that made people laugh. Over those 20 hours, I attacked the producer, was hallucinating and running round – incredible pain. However, you see the reverence and respect they have for the ritual once you’ve been through it. I was in a new world. Amazingly, to be considered a true hunter in their tribe you have to go through tucanderia 20 times in three years. I think once was enough for me!

What beast were you searching for in Brazil?

The mapinguari. To the tribe, it’s something of an ecological superhero that gets you if overexploit the forest. It has a bogeyman aspect: it’s said to be ten feet tall, with a mouth in its chest, backwards facing feet, awful smell, one eye and terrible cry. The locals all claim that it’s real and a few claim to have seen one. When you look at the evidence, it points to the mapinguare being a giant tree sloth, a species that was supposed to have died out 10,000 years ago, around the time that men could have arrived and hunted it down.

But you think there could still be one out there?

If you’re in a place that’s remote, that’s only populated by uncontacted tribes – and there are many left in the jungle that are uncontacted – add to that the idea that the local people fear and respect them and they could still exist. In fact, the idea of eating one is anathema to the locals. They think that all living things are made from clay, and so can be eaten, apart from the mapinguare, which is made of something else entirely. There could easily be a surviving remnant population out there. The fantastic descriptions I heard all have a grounding in reality. Sloths can have a v-shaped scent gland in their chest that might look like a mouth. It certainly smells bad. Their feet are turned underneath themselves, and they give a very infrequent but distinctive high-pitched cry. The descriptions and positive ID we had on artists impressions fitted so well with a ground sloth, I can’t see any other creature that it could be.

Beast Man begins on the National Geographic Channel Monday 7 February at 8pm. Find out more about the series at NatGeoTV