Cumbria is today a largely rural county outside of the main conurbations, however in the relatively recent past the area supported a large amount of heavy industry, especially along the west coast. Much of this industry resulted from the exploitation either directly or indirectly of the mineral wealth, especially Iron ores that are found here. Today, some of our best Brownfield sites are associated with the Iron and Steel industry that had its stronghold on the west coast.
Firstly there are the sites of the former iron and steelworks themselves, at Millom Ironworks Local Nature reserve, at Workington south and north of the River Derwent and at Maryport. There are also the former iron ore mining sites, the best of which is now Hodbarrow RSPB reserve and finally there are also old limestone quarries such as Clints Quarry reserve near Egremont the output of which was used in the steel making process.
These sites are frequently ‘used and abused’ by local people undertaking off road cycling and motorcycling, and sadly, illegal waste tipping. However none of these detract from the butterfly interest and in fact the soil disturbance resulting from cycling and motorcycling is beneficial for pioneer plant species that are important larval foodplants.
The main threat comes from total loss of the site as a consequence of re development, a real and current threat to those sites that are not currently owned by conservation bodies.
Habitats of Brownfield Sites
One thing all these old sites have in common is that they now host a variety of niche habitats with a varied vegetation structure containing scrub and thin often, alkaline soils with many bare patches. This habitat encourages ‘pioneer’ plants suited to rapidly colonising disturbed soil such as Kidney Vetch and Birds Foot Trefoil that are important larval food sources for butterflies.
Our former industrial sites, are the only places in Cumbria to find the Small Blue, and are also good sites for the Wall Brown, Dingy skipper and Grayling as well as the more common grassland species.