Habitat changes in British lowland landscapes and their
implications for bird populations

by Rob Fuller

1. Introduction

The British countryside is a creation of man shaped, and sometimes reshaped, to suit human needs over several thousand years. The pattern and character of the countryside over substantial parts of the lowlands dates back many hundreds of years. Rackham (1986) draws a fundamental distinction between this, the ancient countryside, and the planned countryside that is mainly a product of the Enclosure Acts of the 18th and 19th centuries. These Acts effectively re-structured the countryside in those regions where open-field agriculture was predominant, creating enormous lengths of hedgerow where previously there had been little. To this day, the diversity of habitats for wildlife tends to be greater in ancient countryside - there is generally more woodland, more heathland and the hedges are far older and frequently more complex in their plant communities. The plant and animal communities in these ancient cultural landscapes have gradually developed over many hundreds of years.

If taken too literally, the division of the countryside into ancient and planned is a simplification that overlooks the fascinating local variation that occurs in our lowland landscapes. Nonetheless it is a useful starting point for a discussion of the enormous changes that occurred in the fabric of the countryside since the 1940s and their effects on wildlife. The 20th century saw a revolution in land management made possible by huge technological advances; change was implemented over much of the countryside with a rapidity that would have been unthinkable just a few decades earlier. These events generated wide concern about the effects on wildlife and it was against this background that national monitoring of bird populations was established in British farmland and woodland. This account focuses on the responses of birds to these habitat changes which were the most profound since those brought about by the Enclosure Acts. Three main drivers of these changes can be identified, each of which is considered separately below. The most significant was a sustained campaign to raise agricultural productivity, the second driver was forestry and changes in traditional woodland management, and the third was the expansion of the built environment as housing, industry and roads took up more land.