I was struck by how many of the sites I’ve visited during this trip have been reclaimed from industry. Of course most Wildlife Trust nature reserves are habitats that have taken hundreds of years to establish and are now saved for the future, but something the Trusts are very good at is bringing wildlife back to areas that have been used for quite different purposes.
Gwaith Powdwr, at Penrhyndeudraeth, is one such site. In the 1970s it was the most sophisticated nitroglycerin manufacturing plant of its kind in the world. Production stopped in 1995, and it was decontaminated before being donated by ICI to North Wales Wildlife Trust, Ymddiriedolaeth Natur Gogledd Cymru, in 1998.
Due to the security requirements of the site, nature survived undisturbed in parts of the site, the heathland in particular has remained mostly ungrazed and is a haven for species such as adder and nightjar.
Wildlife started to reclaim the rest of the site once the factory was closed, bats moved into the buildings and structures and the site is now designated as a Site of Special Scientific Interest because of its importance for bats, especially the rare lesser horseshoe bat.
At the end of July, we joined Rob Booth, Living Landscapes Officer at NWWT, and his volunteers for their lunch break. They were busy getting ready for Party Penrhyn, an annual event at the site. Rob told us about the wildlife on the reserve and the work that is being done to encourage more wildlife.
The reserve provides ideal conditions for four kinds of reptiles. We saw lizards basking on old wood and bare patches of ground amongst the heather, and were given permission to peak under some reptile monitoring sheets, where bronze-sheened slow worms glinted in the sun before slipping further into the thatch of grass and old bracken. Adders are also to be found in the heathy parts of the site, but sadly not by us, although we searched carefully. In the midday heat they are far too quick for mere humans and would have been off as soon as they heard us coming. (Although snakes don’t appear to have ears, they can in fact hear, by sensing vibrations, including sound waves, which are passed through their jaw to an inner ear.)
As the reserve is so important for bats, much of the management is aimed at improving conditions for them. Lesser horseshoe bats use the tunnels and there are up to 30 hibernating on site but they don’t seem to breed there. The Trust managed to get a grant to re-roof one of the explosive storage sheds, and are hoping it will become a maternity roost. Since the work was done, brown long-eared bats have bred in there and Rob said that lesser horseshoe bats are already checking it out. The Trust is also working to make the bunkers more homely for bats, putting new doors on to prevent disturbance, reduce light levels and draughts and make them safer from predators.
The woodland on the reserve is particularly good for moths, the Trust found 130 species in just one night. Where a stream runs through the woodland, the damp, shady conditions are ideal for ferns and mosses.
Ponds were part of the industrial legacy, providing water to help keep the explosives cool (and therefore stable) and also allowing contaminants to settle out of the water. These settling ponds are now a wildlife haven, we saw lots of tiny toadlets setting off on their journey into the big world of dry land, stragglers from the great toadlet exodus that happens during July. The grass snakes that have been seen around the ponds proved elusive, which is probably fortunate for the toadlets. Dragonflies and damselflies darted across the water, rarely settling long enough to have their photographs taken, except by the most patient of photographers. Fortunately I had one with me.
We had such a brilliant time exploring Gwaith Powdwr, everywhere we looked there was interesting wildlife. It is a fantastic example of how a site can be restored after such intense industrial use.