The impact of agri-environment schemes on Scotland's biodiversity.
230 scheme farms (Countryside Premium (CPS), Rural Stewardship (RSS) or Organic Aid (OAS)) were surveyed each with a paired, nearby non-scheme farm in order to compare biodiversity between farm types and (for RSS) to compare change in biodiversity over time. The CPS farms supported more wildlife (individuals and species) than the non-scheme farms. The RSS farms were also richer in wildlife than the non-scheme farms during both surveys. Biodiversity increased on the RSS and non-scheme farms between surveys, but the rate and nature of this increase was not significantly different. There were no differences in biodiversity between the small sample of OAS and non-scheme farms.