We often assume that housing and other developments should take place on brownfield sites in order to relieve the pressure on green belt land and open spaces.
Sometimes that`s right, but look a little deeper and you soon start to think, as the song says, "it ain`t necessarily so".
Brownfield sites can be something of a lifeline for rare and endangered insects and invertebrates.
As I understand it, there are two main reasons for this ;
One is that changes to agriculture and the countryside mean that some species no longer prosper in rural areas where they used to be common.
The other is that the wildflowers that some species feed on can actually do quite well in an arid environment (because they have a chance to thrive without competition from more vigorous plant types which rely on richer soil).
The organisation Butterfly Conservation points out that "low nutrient, thin or contaminated soils, with areas of bare and uneven ground...can provide a habitat with an abundance of nectar-rich wildflowers and foodplants" but notes that "these are the type of sites often overlooked for their wildlife value and are often ear-marked for development or landscaping."
All is not lost, however, and they also state that current legislation and planning guidance means that "developers and planners can no longer ignore brownfield invertebrates."
Fortunately, they have found that "brownfield wildlife can co-exist with industry and regeneration."
I believe that the Wildlife Trusts* provide some information and advice on this, but for now we will return to Butterfly Conservation who are running a Butterflies and Brownfields Project which focuses on former industrial sites such as quarries, railway lines, former collieries, demolition sites and former landfill sites.
Two leaflets of theirs, `Brownfields for Butterflies` and `Butterflies in Towns and Cities` can be downloaded from their site.
Butterfly Conservation can be found at www.butterfly-conservation.org .