A slagheap safari in Wales

The hills are alive with rare plants and bugs

Wales is ambivalent about its coal tips – part shared legacy, part perceived threat. But scientists are finding rare species of insects, plants and animals in these unloved, little-visited landscapes. Entomologist Liam Olds took Karen Thomas on a guided tour

As you read this, many UK plants and animals will have hunkered down for the winter. But somewhere on a derelict hillside deep in the South Wales valleys, the Beast of Beddau is stirring in its lair.

It’s seven years since freelance entomologist Liam Olds and his colleague Chris Lawrence found Cranogona dalensi mauriès on Cwm Colliery’s coal tip outside Beddau in the Rhondda Valley. This tiny, off-white millipede, native to the Pyrenees, is less than 6mm long and has seven or eight lenses in its eyes. The sighting at Beddau was a UK first. Excited reports nicknamed it the Beast of Beddau.

It joins the Maerdy Monster, which Olds and millipede expert Christian Owen discovered in 2015 on another Rhondda coal tip. The 12mm millipede Turdulisoma helenreadae was the first new arthropod named in the UK in a generation. These finds led Olds to launch the Colliery Spoil Biodiversity Initiative.

Olds is the grandson of a Rhondda collier who managed the ponies below ground. As a child, Olds walked his dog on the local tip. “I’d see grass snakes, common lizards and dragonflies – it felt like my own personal nature reserve. It’s why I studied zoology at university.”

The Museum of Wales hired him as a Natural Talent apprentice, specialising in colliery-spoil invertebrates. Olds spent three years working with experts and citizen scientists to record plants, invertebrates and larger wildlife on eight old tips in Rhondda Cynon Taf and seven in Neath Port Talbot. Between 2015 and 2018, the surveys recorded 900 different species.

Just one Welsh spoil tip is designated a nature reserve. And of Wales’ 2,500 legacy tips, Olds has surveyed just 20. He wants to map and monitor all of the country’s tips to discover what lives there and to protect and value these habitats as our climate changes and as more and more species risk becoming extinct.

Summer coal-tip safari

It’s a muggy late-summer afternoon. Storm Betty has been and gone; torrential rain has turned the hills above Beddau a shimmering green. Olds pulls in below a clump of brambles and we walk up a slope that would pass for a regular Welsh hillside. But the hill is Cwm Colliery’s spoil tip – a vast heap of debris ripped from the earth.

Cwm produced its first coal in 1914, expanding in the 1950s to join up with Coed Ely colliery 5km away. At peak production in the 1970s, 1,500 men mined half a million tonnes of steam coal a year. Having survived the mid-1980s year-long miners’ strike, Cwm closed in 1986, taking 800 local jobs. The coke works followed in 2002.

The legacy is scattered all around – twin chimneys rise from the valley floor – but the place is deserted. The tip’s only visitors are quad bikers and occasional dog walkers; local people mostly stay away. Undisturbed, nature has reclaimed the nutrient-poor soils. “It’s an open mosaic of habitats,” Olds says.

Soon, the grassland flattens into a plateau. The mosaic takes shape: scrub, young and mature broadleaf woodland, boggy mud, waterbodies with and without reed beds, calcium-rich springs and watercourses stained orange with iron. Within this multitude of microhabitats, rare plants, invertebrates and amphibians thrive.

“The geology and pH levels are really complicated,” Olds explains. “You get this strange mix of acid, neutral and calcareous flora, all co-existing in the same area.”

We traipse past common species: knapweed, wild carrot, scarlet pimpernel, blackberries, oaks and silver birch. There are also rogue invaders: cotoneaster bushes and trees, Himalayan balsam and pearly everlasting, an Asian/North American daisy planted on miners’ graves.

Olds has found plants not seen since the 1960s on older areas of the tip. “It’s ironic,” he says. “We’ve lost so many habitats around these tips, but flora and fauna have colonised from those lost habitats. Parts of these tips become time capsules.”

We pass an abandoned badger’s sett and the crushed corpse of a mole. We spot a common frog hiding in the leaves. A huge black-and-gold dragonfly clicks past at speed and a buzzard caws high above the trees.

An ornate-tailed digger wasp pops out of a hole in search of lunch, scouring the earthen bank for beetles. Clumps of kidney vetch feed the caterpillars of rare small blue butterflies. Dingy skipper caterpillars feast on birdsfoot trefoil.

Because coal tips are mostly hot and dry, they draw species native to sand dunes. Olds has recorded slow worms and adders, brown-banded carder bees and water rails. He’s seen a thick-margined mini mining bee thought to have vanished from Wales in the 1960s.

The UK is one of the most nature-depleted countries in the world; climate change, industrial farming and pollution are pushing more species to breaking point. The State of Nature report published this autumn found that one in six UK plants, mammals, insects, birds and amphibians is facing extinction. Against the odds, nature clings on in old spoil tips.

Surveys have recorded 100 bee species on Welsh tips, 60 species of lichen and 100 different mosses, many of them rare. New finds come thick and fast. Near Tower Colliery, 35km, fungi experts found Cudoniella tenuispora – thought to be extinct in Wales – growing out of pine cones. Another tip has ballerina waxcaps – fungi seen only on centuries-old pasture.

Coal tips’ troubled past

The way in which these sites have flourished undisturbed says a lot about Wales’ troubled relationship with its coal tips. In 1966, spoil collapsed onto a school at Aberfan near Merthyr Tydfil, killing 28 adults and 116 children. The disaster remains an open wound in Wales.

In 2020, Storm Dennis tore through South Wales, bringing torrential rain that saturated and weakened a spoil tip near Tylorstown. It caused a 60,000 cu m landslide that blocked the valley and damaged sewers and a strategic water main.

Thankfully, no one was hurt, but public outrage pushed the Welsh government to review safety at all 2,456 tips to determine whether climate-linked storms, floods and droughts are destabilising them, and review the current legislation relating to disused coal tips.

The Law Commission concluded that the laws and regulations around the management of spoil tips are “no longer fit for purpose”. The safety review found that 300 tips are high risk, but the Welsh government has declined to name them. The Senedd is to discuss the Coal Tip Safety Wales Bill, to replace the 1969 Mines and Quarries (Tips) Act, in the new year.

Olds and his fellow scientists counter that this leaves 2,000 tips that pose little to no risk and that – with a nature-loss emergency that’s every bit as urgent as the climate crisis – we must value and protect these sites as precious habitats that could be damaged by work to repair them.

However, until we know which plants and animals live in our spoil tips, it’s impossible to set priorities to protect and conserve them. Several other countries – notably Poland and Germany – have conducted considerably more research to determine which species live on old spoil tips.

“Almost all these sites have really high biodiversity value – locally, at county level and often nationally too,” Olds says. “We’re talking about species designated a conservation priority in Wales and the UK. That’s incredibly important, but we’ve only looked at a really small proportion of these sites.

“If just 10 per cent of these sites have really high biodiversity value, that’s 250 sites whose quality may be better than most nature reserves. I honestly do believe that. That’s a massive resource for Wales. If we’re serious about tackling the biodiversity crisis, we need to look after landscapes that harbour nature. And in the South Wales Valleys that means our coal tips.”

That work needs funding and resources, but it also needs a new mindset – for the public to see tips as places of wonder not threat, and to value these spaces for wildlife without putting new pressures on plants and animals that have thrived undisturbed.

It’s a tricky balance – budgets are tight and local authorities need to build new homes. In July, Rhondda Cynon Taf Borough Council agreed an £8 million funding package to tear down Cwm Coking Works to build 600 new homes. Nature comes low on the list of priorities.

“It’s unrealistic to think we’ll protect all of these sites from all of the pressures they face, whether from development and land reclamation or public safety,” Olds says. “There are new pressures from solar farms – fitting panels across sites is no good for species that need open ground. But we could at least protect the most biodiverse sites – perhaps one in every county.”

Mapping which species live on which sites would be a start. “It’s their complexity that makes these sites interesting,” Olds concludes. “Each is very different. You can’t know what to expect. They’ve all been left to revegetate.

“Rewilding is popular now – but it’s already happened here, across the South Wales coalfield. It shows the power of nature. All these rare species prove that nature can thrive – if we let it.”


out more: www.collieryspoil.com

This story is published in the November 2023 issue of The Environment magazine

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