MARINE scientists have for the first time explored an underwater mountain higher than Ben Nevis, situated off the west coast of Scotland - and found it teeming with life including populations of deep-sea corals.

The Hebrides Terrace Seamount is one of just three seamounts in the UK's seas. Its peak is 1,000m beneath the surface.

Researchers at Heriot Watt University in Edinburgh used a remotely operated submersible vehicle to explore the aquatic mountain slopes and watched from a ship-based laboratory on the surface. They found it to be densely colonised with more than 100 species ranging from deep-sea fish, octopuses and strange single-celled creatures.

Marine biologist Prof J Murray Roberts, who led the research, said: "When the vehicle dives down it goes a kilometre through the open water and then this strange place opens in front of you."

The corals support rich communities of other species and play a critical role in the life history of species that range far beyond the UK's shores, such as threatened deep-sea skates - related to sharks - which lay their eggs on them.

But the scientists say the oceans are becoming more acidic, primarily because of carbon emissions. The footage captured by the scientists could be the first and last snapshot of a unique marine environment.

Prof Roberts added: "In the Pacific there are many thousands of seamounts but off Scotland we have the only seamounts there are in the UK. Nobody had ever dived it or seen what was growing on the sides of this seamount.

"There were at least 109 different taxa down there, all the way from really strange single-celled organisms to clusters of deep sea corals. I was surprised to see the diversity that we saw.

The Hebrides Terrace Seamount is the UK's highest underwater mountain standing 1,400m above the surrounding seafloor. Ben Nevis is 1,344m above sea level.