has photographed the colony of around 4,000 animals and released the pictures of the elusive mammals

The little Japanese horseshoe bat, Rhinolophus cornutus, is a species of bat in the family Rhinolophidae

have found the eastern bent-winged bats' hide-out in an

have been baffled about the bats' disappearance during the winter months for years


Their disappearance during the winter season has baffled environmentalists for years.

But now researchers have solved the mystery of where thousands of bats hide during the cold weather in Japan.

They discovered thousands of eastern bent-winged bats seeking sanctuary from the winter weather in a public walkway in the mountains of Kochi.

Researchers have solved the mystery of where thousands of bats hide during cold weather in Japan. A photo of the vast colony is shown

The experts discovered thousands of eastern bent-winged bats seeking sanctuary from the winter weather in a public walkway in the mountains of Kochi. The huddled animals are shown above

Incredible images, taken by university researcher Kei Nomiyama, show a colony of around 4,000 bats hibernating in a man-made cave.

It took years of research to locate the animals, which are also known as little Japanese horseshoe bats.

But they were discovered hiding in the mountain on Shikoku Island - the smallest of the four main islands of Japan.

The little Japanese horseshoe bat, Rhinolophus cornutus, is a species of bat in the family Rhinolophidae.

It is found in Japan and possibly China.

Incredible images, taken by university researcher Kei Nomiyama, show a colony of around 4,000 bats hibernating in a man-made cave. Here is a close-up of their faces

It took a lot of research to locate the animals, which are also known as little Japanese horseshoe bats (shown)

The scientists discovered thousands of the bats escaping chilly weather in the mountains of Kochi (marked on the map above)

But they were discovered hiding in the mountain on Shikoku Island - the smallest of the four main islands of Japan. A number of the tightly-packed creatures are shown above

THE AGILITY OF BATS Bats are able to perform breathtaking aerobatics in the dark because their wings are equipped with highly sensitive touch sensors, researchers have found. A bat's wing contains cells that respond to even slight changes in airflow, allowing the animals to dip and dive according to their surroundings. Scientists have discovered how sensory receptors in bat wings send information about airflow to neurons in the brain, enabling the bat to make split-second flight control adjustments. Advertisement

Its natural habitat is temperate forests and it is threatened by habitat loss, but has not yet been assessed for the IUCN Red List.

This is a comprehensive list detailing the global conservation statuses of animal, fungi and plant species and their links to livelihoods.

Researchers believe there are just under 41,000 of the bats left, after a population decline of 67 per cent since the 1990s.

'For many years bat researchers were looking for a winter colony, however we realised that they completely disappeared,' Mr Nomiyama explained.

'This phenomenon was a complete mystery for researchers.

'After many years we finally found this valuable colony. This was huge delight for us.'

During the winter months when temperatures drop to just above freezing, the bats go into hibernation in caves.

Mr Nomiyama, who lives in the city of Matsuyama said: 'The artificial bat cave exists up in a mountain in Shikoku Island. 'In order for me to reach the cave, I have to drive for about three hours by car from my hometown.'

During the winter months when temperatures drop to just above freezing, the bats go into hibernation in caves

Mr Nomiyama, who lives in the city of Matsuyama said: 'The artificial bat cave (part pictured) exists up in a mountain in Shikoku Island'

The photos show the tiny little animals grouped together (pictured) and flying through the artificial cave where they have set up home for the winter

The photos show the tiny little animals grouped together and flying through the artificial cave where they have set up home for the winter.

Although the exact location of the cave is unknown, as researchers cannot give away the precise location, it is understood it is actually a channel used to access a mountain.

The eastern bent-winged bat gets its name from its unique anatomy - on the third 'finger' of its wing, the last bone is four times longer than the middle one, giving a bent appearance.

The eastern bent-winged bat gets its name from its unique anatomy - on the third 'finger' of its wing, the last bone is four times longer than the middle one, giving a bent appearance (seen above)

Although the exact location of the cave has not been revealed, as researchers can't give away the precise location, it is understood it is actually a channel used to access a mountain. A small cluster of bats is shown

The disappearance of the species of bats during the winter season has baffled environmentalists for years

Researchers believe there are just under 41,000 of the bats left, after a population decline of 67 per cent since the 1990s.

Mr Nomiyama said: 'The number of these bats decreases every year in Japan.

'This may be due to the influence by environmental destruction.'

Researchers believe there are just under 41,000 of the bats left, after a population decline of 67 per cent since the 1990s. Several hundred are shown above

Mr Nomiyama added: 'The number of these bats decreases every year in Japan. 'This may be due to the influence by environmental destruction.' A number of flying bats are seen in a passageway to the cave