I’ll try not to bang on about this for too long but, if you want to save wildlife from development you have to do it at the Local Development Framework (LDF) level or above i.e. Regional Spatial Strategy. It’s at LDF level that site allocation is done and where you can set the ground rules for the developers to follow. If the planning guidance for your area is written correctly to save wildlife by protecting all the relevant wildlife sites and corridors then the developers can’t build on them. PPS9 (
http://www.communities.gov.uk/docume...ing/pdf/147408) is the government's policy on how planners should deal with nature conservation and development and you should comment on your local plan when it’s being revised. If you don’t then it’s difficult to complain about individual developer’s plans when they are only following the rules set out by the Council which you could have commented on when they were being written.
Further, the Development Plans dictate what a developer is expected to include in a development e.g. no net loss of biodiversity, improved environmental corridors to adjacent sites etc. Knowing this he can buy the land at a price that allows him to make a profit and keep the wildlife. The land value is determined by what the developer can build on it and if the wildlife compensation is not included in his financial calculations before he buys the land then getting ecological compensation is virtually impossible. A recent example of good practice was Leeds City Council Supplementary Planning Guidance on Biodiversity and the Waterfront (
http://www.leeds.gov.uk/files/Intern...700c5756d9.pdf ) which describes to developers what they need to consider when building close to rivers and therefore they can decide how much to pay for land zoned for development adjacent to rivers.
Dealing with the social issue of nature conservation which has crept into the thread above, the Greater London Authority has been consulting on their Access to Nature Conservation document (
http://www.london.gov.uk/mayor/strat...-to-nature.pdf ) This states that wildlife areas provided by developers need to meet certain ecological criteria before they can be counted. While the ecological standard required (locally called of ‘Borough Importance’) is not a high hurdle, at least it tells the developer what he has to achieve, so he can factor that into his development and hence the land price.
Fighting for ecological mitigation on individual sites must carry on as few planners know anything about nature conservation, however it’s really a last resort and is a result of failures within the planning system and generally leads to compromises and a slow degradation of the local ecology through cumulative impacts.
As for the ecological value, rather than social value of brownfield sites (which vary from demolished buildings with a couple of Buddleia to Rainham marshes SSSI) , I’ve often had this debate with planners and wildlife trusts. Yes, they can be ecologically rich especially for invertebrates and specialist plants. The problem is that they are generally used by pioneer species which are out competed as the site undergoes ecological succession. Therefore, you either need to manage the site to keep it disturbed (which costs money) or you need a supply of new brownfield sites which species can move to as the old sites become vegetated or developed. In large urban areas this shouldn’t be a big problem as there are always new derelict areas being produced, although high land prices in some cities can cause problems as sites are developed very quickly. However, in general there are normally enough derelict sites about that only particularly important brownfield sites justify conservation protection.
I’ve gone on for too long so I’ll stop there.
Cheers, Chris