AN ICE AGE LANDSCAPE: THE MERES AND MOSSES

Anyone perusing Ordnance Survey maps of the northern parts of Shropshire will quickly realise that there is an unusual density of lakes, pools and mosses in the area. Names such as Pikes End Moss, Whattall Moss, Sweat Mere, Colemere, The Mere and Berrington Pool litter the map. Further study of neighbouring maps shows that these features also occur across county borders and into Cheshire, Staffordshire and Clwyd. Faced with this unusual preponderance of "wet" landscape features many people will ask themselves why are there so may of these pools and mosses here?

For the answers we need to step back in time about ten to twelve thousand years ago, when the last ice age retreated from the area. The vast ice sheets had carried huge amounts of sand, gravel and rocks across the country. This material had been dumped as the ice sheet retreated, leaving a loose mix of sands, clays and rocks. Next, there was a small re-advance, when colder conditions temporarily returned. This caused the ice sheet to push south again, piling up the glacial deposits in front of it, rather like a massive bulldozer moving across the landscape.

As conditions warmed once again, the ice sheet melted and retreated northwards. As this happened vast quantities of materials were washed out from the ice sheet and deposited over and around the previously "bulldozed" up material. The result was a great deposit of materials we call a glacial moraine and it is this feature that is responsible for most of the meres and mosses we see today.

Over the thousands of years since the moraine was formed, it has weathered to form the hummocky landscape now so familiar in parts of Shropshire. Good examples of this landscape are around Ellesmere and Whitchurch. Ideal for the formation of meres and mosses, the undulating landscape provided basins in which pools could form. In places, lenses of clay deposited within the moraine would hold up the water table, so that pools quickly formed in some hollows in the landscape. Some pools remain today as the meres we know so well, whilst others gradually filled with the remains of dead vegetation to form marshlands, or where acidic conditions prevailed, they would form peatlands - the mosses.

Today the meres and mosses of the Midlands are one of the most precious of the nation's wildlife resources. Many are nature reserves and others are Sites of Special Scientific Interest, while a whole series of meres and mosses is designated for protection under the Ramsar convention on wetlands of international importance. These are indeed special places!

In common with most wildlife habitats, the meres and mosses have suffered over the last half-century, most notably from a decline in water quality. Lack of traditional management has also impacted on some sites, so that they have tended to scrub over, losing much of their wildlife interest. Invasions of alien species such as Australian swamp stonecrop and Canada geese have also taken their toll, ousting native species and degrading marginal plant communities around many of the meres. There have been some depressing losses from Shropshire, including the beautiful grass of Parnassus, an enigmatic plant that has now virtually disappeared from Shropshire.

Thankfully there is good news to counteract the rather discouraging picture of decline. Ranking as one of the Shropshire Wildlife Trust's finest achievements was the campaign to save Fenn's and Whixall Mosses in the early 1990s. At that time this large area of moss was rapidly being trashed for peat extraction. Conservationists looked on in resigned dismay as one of the last truly wild and magnificent wildlife features of the region was being sacrificed to the horticultural industry.

The Trust quickly realised that this was a real litmus test for the environmental credentials of the government and they launched a brilliant campaign that involved helicopter fly-overs, television and radio coverage and plenty of column inches in the national press. In response to the outcry, the government agency for nature conservation, English Nature (as it was then) and the site's owners responded commendably fast. Soon English Nature was able to announce the purchase of much of the site as a National Nature Reserve.

Since then Fenn's and Whixall Mosses have been re-wetted and managed very positively, with further land acquisition adding to the size of the reserve. There have been some spectacular gains here and today 1,900 species of invertebrates thrive on these Mosses; large heath butterflies, white-faced darter dragonflies, bog bush-crickets and raft spiders, back from the brink of extinction, are spreading from their refuges in the old peat cuttings. In spring, calls of breeding teal, mallard, curlew, skylark and meadow pipit fill the air, and yellow four-spot chasers dart. In summer sunshine, hobbies catch dragonflies, and 'churring' nightjar hoover up clouds of moths.

Elsewhere, sterling work has been done to control the spread of Australian swamp stonecrop at Brown Moss, there has been much positive management at Colemere and of course the Wildlife Trust have put in hand work to clear much of Wem Moss of unwanted scrub. Most encouragingly, a new Defra initiative to make farming more sensitive to river catchment needs has been launched and one of the early target areas is the meres and mosses. The aim of this initiative will be to help farmers to manage their land so that the impacts of their activities on water quality are reduced. Declining water quality is one of the key threats to the meres, so this can only be good news. To add to this positive work, a Biodiversity Enhancement Area for the meres and mosses has been announced. This will see Natural England and a whole range of partners working together to protect and extend the existing meres and mosses, but also, where the opportunities arise, to provide new wildlife habitat in what it is hoped will become an outstanding area for wildlife and landscape.

The meres and mosses are outstanding for their wildlife. Their birdlife is particularly varied and a trip to Ellesmere in the breeding season will yield great views of nesting herons. The winter months promise good numbers of teal, wigeon and pochard, as well as plenty of other wildfowl in smaller numbers across the series of meres. The mosses harbour some of our rarest and most impressive invertebrates, including the raft spider, a large and flamboyant caddis fly - Hagenella clathra and of course dragonflies and damselflies abound on both meres and mosses. There's plenty for the plant hunter too. A trip to Brown Moss can yield one of the most extensive lists of flora for any site of similar size, while at Colemere one can view England's only site for least water lily.