SCIENTISTS say they have discovered a "lost world" of strange creatures living deep in the waters surrounding Scotland's remotest outpost.

Researchers from Marine Scotland found the unique ecosystem, made of unique bacteria, corals, unusual anemones and clams that eat methane-munching microbes, on the sea floor near Rockall.

It is thought to be the product of a process known as a 'cold seep', where gas from deep in the earth leaks onto the sea bed creating an environment capable of supporting rare and specialist bacterial communities that then form the basis of the food chain.

The area was first identified in 2012 when scientists spotted previously unknown creatures brought up from the seabed, and has now been confirmed following an expedition by a survey team onboard the Marine Scotland research vessel Scotia.

These types of marine ecosystem were only discovered in the 1980s, and the one off the coast of Scotland is the first to be found in this area of the North Atlantic, with the nearest other examples being off the coast of Norway and in the Gulf of Cadiz, Spain.

The research expedition sailed on 16 July with a full board of scientists and a suite of sampling tools including towed HD cameras, seabed corers, sediment grabs and baited cameras.

Following up on the previous cruise, the ship sailed to the area where the evidence had first been found and located the cold seep, described as a "needle in a haystack", within an hour of searching.

Dr Francis Neat, the Marine Scotland scientist who led the search said: “It was unlike any seafloor any of us had ever seen before – strange thick green and white rippled patches with lots of flocculent matter everywhere.

"These were almost certainly the bacterial mats that are typical of cold-seep ecosystems. The following day we got out first glimpse of active seepage from the seafloor – sediment rich puffs of fluid being emitted beneath odd pillow like formations.

"We got lots of core samples of the sea-bed – stinking with the bad egg smell of hydrogen sulphide – again an indicator of hydrocarbon associated seepage."

"So, there is a little doubt now that there is a very unusual cold seep ecosystem out there. Exactly what it is and what is causing it and what sorts of new species it might harbour remain to be confirmed as it will take some time to process all the samples."

The project was a collaboration between Marine Alliance for Science and Technology for Scotland (MASTS) and Marine Scotland, Oceanlab, British Geological Survey (BGS) and the Scottish Association for Marine Science.

Efforts will now be made to analyse the samples that have been taken and to establish what types of creatures make their home there.

The agency's previous surveys around Rockall caught a frilled shark, an ancient "living fossil" species of shark that dates back at least 90m years and is rarely seen in northern waters along with unusually large adult cod, saithe and haddock, suggesting Rockall's waters were very rich in food.

Dr Neat said that there was no doubt that the ecosystem is very special and deserves further more investigation.

He added: “ It’s like finding a patch of tropical rainforest that no one else has seen. A true lost world, revealed, it is equally fascinating and far more challenging to study.

"It’s also a great success story for how science works. You get the clues, you follow the hunch and make the discovery – and it shows how working together and pooling complementary expertise from the MASTS community resulted in a new discovery, the significance of which we can only guess for now."