As the largest living land predators in the world and capable of running at speeds of around 30mph (48kmph), brown bears can be extremely dangerous.

Attacks on humans can be fatal and are more likely if bears are surprised or someone comes between a mother bear and her cubs.

Yet on the Shiretoko Peninsula of Hokkaido, Japan – an area recognised for having one of the planet’s most densely packed brown bear populations – bears are no longer feared by the people living there.

We are not scared of them

For part of the year 200 bears share the remote wilderness with seasonal fishermen who, like the animals, are dependent on the autumn salmon run.

The bears roam freely around the small base used by the men, a surprisingly relaxed co-existence captured by the BBC series Japan: Earth’s Enchanted Islands in the clip above.

“It’s a part of our life. Even though bears appear, they just pass by around here. We are not scared of them, it is just natural,” explains Mr Oose, a fisherman with 50 years' experience on the peninsula.

Living side-by-side with each other hasn’t always been so harmonious, though. In the past, fishermen would ask hunters to kill any bears that came too close to their camp and there is still evidence of an electric fence that was once used to keep bears out.

But gradually the fishermen grew to realise that the bears weren’t as threatening as they once feared.

“It did take time, many years, in fact. We used to make loud noises by hitting an oil drum whenever we saw bears because we were frightened. However, the bears didn't seem to be alarmed by the sound and they didn't go away. But they didn't approach in order to attack us either,” Mr Oose says.

“There are a lot of bears now, but bears don't do any harm to human beings, and we don't do anything to them either.”

The fishermen have now learned to stare at any bear that gets too close, as well as to pay attention to warning signals given by the bears. Cubs are also taken to the fishermen’s base by their mothers, for what could be thought of as 'lessons in how to behave around humans'.

It is this long-established relationship that allowed cameraman Graham MacFarlane to film the bears’ salmon hunting skills at close quarters.

The first few days I stayed very close to my vehicle just to feel my way with how they might react

“At first it was quite intimidating leaving my vehicle to try and get good filming positions, especially after seeing how fast they are when hunting salmon in the river. At a rough guess I estimate the bear could run four times faster than me over the rocks and pebbles of the beaches and river beds,” he tells BBC Earth.

“The first few days I stayed very close to my vehicle just to feel my way with how they might react. After this time I became a lot more confident and ventured a little further from the car to get better filming positions but I always had my escape route in mind, just in case.”

While this unique relationship may be flourishing in a protected environment for animals, the bears’ boldness around humans does cause alarm when they venture into the urban areas that border the peninsula.

“When [bears] get into town and walk around it causes trouble and they have killed a bear in the past for this behaviour,” says Masami Sugano, who has conducted research into the bears for the Shiretoko Nature Foundation.

“For this reason, if the bears get too close, they try to scare them off by using fireworks or rubber bullets and teach them to fear humans.”

UK viewers can find out more about the animals that live on Japan's wildest island in the concluding episode of Japan: Earth's Enchanted Islands.

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