Grauer’s gorillas are the largest primates in the world and are capable of awesome displays of power and brute strength. But a harmonious family life lies at the heart of society for these elusive and threatened giants. Wildlife cameraman and presenter Gordon Buchanan tells BBC Earth how he attempted to get to know a population of the great apes living deep in a forest in the Democratic Republic of Congo

“When you look at another primate eye to eye… there’s something that’s very special about that and unique because so much of how they look and how they behave is similar to us.”

Although Gordon Buchanan has filmed with families of brown bears, polar bears and wolves, getting close to wild gorillas in Kahuzi-Biega National Park for the series 'Gorilla Family & Me' evoked an unusual connection.

One formidable silverback known as Chimanuka, and his multifaceted role in his 25-strong family as decision-maker, fierce protector and surprisingly tender father, drew a special kind of empathy and admiration as Buchanan got to know the gorilla.

“As a father you have to be lots of different things. You have to be different things for different members of your family. The same goes for gorillas.”

Whatever thoughts I was having about the gorillas they were having their own thoughts about me

Numbers of Grauer’s gorillas (Gorilla beringei graueri) are unknown but are thought to have plummeted in the past 20 years as a result of hunting, human destruction and illegal capture. These problems were fiercely exacerbated by war, which claimed the lives of millions of people between 1998 and 2003.

Now some experts believe the only future for DR Congo's endemic and endangered Grauer’s gorillas is through eco-tourism.

In Kahuzi-Biega National Park, one of the great apes' remaining strongholds, Buchanan and production crew wanted to reveal never-before-seen insight into their family life, and to record the habituation process (getting the gorillas used to human presence), necessary for eco-tourism to succeed.

But how to get close to a tight-knit clan of wild gorillas?

Grauer’s gorillas’ family structure is comprised of a single dominant male and two to 36 females and young.

Get accepted by the silverback, and the rest of the family will follow suit.

“It’s like meeting a kind of mafia don,” says Buchanan, describing getting close to Chimanuka, whose family provided a rare opportunity for him to formulate a relationship with the gorillas, because the group is habituated to human presence in the park.

Key to being accepted was to get close but to keep a respectful distance from the 200kg (440lb) silverback.

“Working in the confines of dense forest you are physically very close together and I think through that proximity there is a two way relationship, you know: whatever thoughts I was having about the gorillas they were having their own thoughts about me,” says Buchanan.

We want all these animals to be much scarier than they actually are. But their size kind of actually distracts you from their true nature… quite happy chilling out and being together and munching away on food

The crew worked under direction of the guides working in Kahuzi-Biega park who protect gorillas from illegal hunters and help to habituate them.

And Buchanan received some tips for gorilla communication from chief guide Lambert.

While an adult male beating his chest can be a way of issuing a warning, when juveniles do the same it is usually a friendly greeting.

Another tip was to use low sounds to keep silverbacks calm, Buchanan explains.

Adult male gorillas will behave aggressively towards what they perceive to be a threat, barking, beating their chests and even charging, throwing forward their incredibly powerful bodies. The animals are several times stronger than a human, possibly as much as eight times as strong.

Making the wrong move with Chimanuka, says Buchanan, “could set you back and could get you into serious trouble”.

Although the crew tried to keep a distance of 7m (23ft) from the gorillas, on more than one occasion the team were the subject of Chimanuka’s “walk-past”, designed to display a silverback's huge size to intimidate.

But once Chimanuka began to relax around the outsiders, the team were rewarded by witnessing intimate and surprising family moments, most notably the powerful silverback’s softer side with his children. Unusually, Chimanuka had taken on the role of both father and mother to his infant son Marhale, whose mother died, gently grooming him and allowing him to follow him closely.

Buchanan says the gorillas’ personalities quickly began to “shine through”, and that he found himself respecting the gorillas as individuals the way he would people, Chimanuka in particular.

“He’s got to be strong, but he’s got to be charismatic; he’s got to be tender, he’s got to be caring. He’s got to be responsible and he’s got to make all the right decisions. Not just for himself, he’s got to make all these right decisions, taking in, I suppose, the complexities of having such a huge family.”

While trying to get close to Chimanuka's and the group was challenging, harder still was filming a gorilla family a team of expert park rangers were still working to habituate, led by a silverback called Mpungwe. Buchanan was one of the few white people the gorillas had seen, and the team of park rangers hoped his presence could help get the clan used to tourists.

At first Mpungwe did not want to be followed, and kept disappearing into the forest whenever he caught sight of the newcomers, taking his family with him. 

But there was a “breakthrough” moment with the mighty silverback, when gorilla and man saw each other over a swamp and Mpungwe appeared to be more comfortable in the open.

“It just gave him that space to kind of properly check me out. And the very next day… he just stayed exactly where he was, and I sat down and then closed the distance and got to within, you know, 7 or 8m of him and he just sat there," recalls Buchanan.

"And if you told me… that was going to happen three days earlier I wouldn’t have believed you."

Is there concern about Kahuzi-Biega park’s Grauer’s gorillas becoming too used to people?

Buchanan argues that the only viable future conservation for the species is eco-tourism, where money generated from tourists could be used to protect the animals and their habitat.

“I think without [eco-tourism], if you said well let’s just… leave them be and hope for the best… within a short space of time the gorillas would disappear and the forest would disappear with them.

“So I think part of their conservation is having this relationship with people that they’re comfortable.”

As for his own role he describes keeping a close, but not too-close distance from the wild animals while filming.

“We always kind of remove ourselves from the natural equation all the time and think that we’ve got no right to be in as part of the wild.

“But actually as long as you’re not… having a detrimental impact on the lives of an animal, I think I’d always be… well why shouldn’t we have these close encounters if it gives you a greater appreciation for these animals?

"If it’s going to conserve them into the future, by all means… see them up close. The closer you are to something, the more you care about it.”

Buchanan cites the classic 1970s footage of Sir David Attenborough, a hero of his, with gorillas, as an inspiration.

Almost 40 years on, Buchanan wanted to try to emulate what Attenborough did “which is to kind of just get to know these animals and to have a kind of respect of them and just to be open”.

So what’s gorilla family life actually like?

Despite the fearsome reputation of male gorillas, Buchanan describes the primates as “really the hippies of the animal kingdom”. Feeding and grooming are often the orders of the day. And when the silverback’s not protecting his family from rivals and other dangers, he can lounge happily with his clan.

“It’s very relaxing”, says Buchanan, describing the family atmosphere.

“I think because they are so big… we want all these animals to be much scarier than they actually are. But their size kind of actually distracts you from their true nature, which is, most of the time… quite happy chilling out and being together and munching away on food,” he says.

“So they’re sort of just big, hippy vegans that occasionally get angry and are good at scaring you.”

UK fans can click here to watch 'Gorilla Family & Me’ on iPlayer.

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