Celtic rainforest in Wales facing extinction crisis, ecologists warns | UK News

An “extinction crisis” is happening in Britain’s temperate rainforests where some of the world’s rarest mosses, lichens and liverworts are vanishing, ecologists have warned.

Also known as Celtic rainforests, temperate rainforests are found primarily along the UK’s western coasts.

A survey of Welsh rainforests in 2024 found only 22% were in a good condition due to pollution, fragmentation and invasive species.

“When this tree came down, in a flash we lost a species,” said ecologist Sabine Nouvet about a 500-year-old oak in Eryri National Park, also known as Snowdonia, which fell during Storm Darragh in December.

The tree was home to one of the UK’s best known populations of a rare lichen, the loss of which was “symbolic of the species crisis, the extinction crisis, that we are facing now”, said Ms Nouvet.

Ms Nouvet, a rainforest advisor with PlantLife, a member of the Alliance for Wales’ Rainforests, said the fallen tree’s bark was once home to more than 60 types of lichen.

The rarest was the minuscule rinodina isidioides – its tiny structures, when seen through a hand lens, resemble its common name, skeletal fingers.

It lives only on trees at least 300 years old and in conditions found exclusively in the rain-soaked valleys of western Ireland and Britain.

Temperate rainforests occur on less than 1% of the planet’s surface and Wales has internationally important examples of the habitat.

The special habitat’s twisted branches, dappled light and moss-covered understorey once covered much of the country, but is now only found in isolated areas including the Woodland Trust’s Coed Felenrhyd near Blaenau Ffestiniog, Gwynedd.

December’s storm “hammered the forests around here”, said Ms Nouvet.

She said at least six ancient trees, described as “grandmothers” of the forest, were lost in Coed Felenrhyd.

The presence of skeletal finger on one of those trees indicated “that this valley has got clean air, it has ancient forest, that this tree was, for some reason, really old and then we lost it”, she added.

There is hope the skeletal finger species can hang on in the valley after clippings were relocated to five other old trees nearby.

Ms Nouvet said the aim was for the clippings to seed the bark below, but the process could take up to a decade.

There is about 33,024 hectares, or 46,000 football pitches, of rainforest left in Wales.

Storms are just one of the threats to ancient woodlands such as Coed Felenrhyd which, according to the State of Wales Rainforest report, cover just 4.3% of country’s rainforest landscape.

Much of this rainforest lacks connectivity to similar habitats because it is surrounded by farms or woodlands planted with non-native species.

Some are grazed inappropriately, the survey said, and many are affected by rhododendrons that smother the forest floor in a dense shade that native species cannot tolerate.

Farmer and retired forester Aled Thomas said the Celtic rainforest had been “grazed since the beginning of time”, leading to the formation of these woodlands.

But conservation efforts in the past saw many ancient woodlands fenced off.

“They have grown wild with invasive species coming in so none of the natural flowers associated with this type of woodland have been present,” Mr Thomas explained.

Mr Thomas grazes small Dexter cattle in Coed y Gribin, a pocket of rainforest managed by the RSPB near Dolgellau.

“They will provide a habitat for a much more diverse species range by their hooves marking the ground, driving in acorns, rolling on the ground and they’ll graze anything and everything,” he said.

“They eat brambles like they are having supper.”

Each animal is fitted with a GPS tracker and an alarm that trains them to keep to areas that need grazing and away from sensitive parts of the forest.

“The landscape has changed dramatically because the cows have been here for about three seasons and you notice there’s very little bracken and there are bluebells coming up.”

Mr Thomas said farms with more woodlands were the key to linking up isolated parts of the rainforest.

“You just don’t need a field for growing cows, you can grow food by grazing in woodland and the benefits from that are huge to the forest and the farm.”

Wales has a global responsibility to protect the Celtic rainforest, said PlantLife’s Adam Thorogood.

“We’ve got a really unique situation here in Wales where we’ve got some vital areas of habitat, a type of rainforest we don’t really find anywhere else on Earth.

“People don’t even realise that we have temperate rainforest here… right on your doorstep.

“It’s there to be explored, there to be enjoyed, and there’s a huge diversity of species of plant but also other flora and fauna.”

He said interest from the public in the Celtic rainforest was coming at a time when it was under enormous pressure and significant investment was needed to secure its future.

Natural Resources Wales has been asked to comment.