Despite the effects of the Industrial Revolution and the pressures of the present day, Britain has more than 30,000 species of animals, and 5,000 species of plants. These numbers are small in comparison with other countries, yet Britain is an important migratory centre for birds, sea mammals and fish. Many species are dependant upon a particular character of landscape. If there is a change in land management, those species may suffer.
Many bird species that are typical of lowland farmland such as the grey partridge, barn owl and lapwing have undergone pronounced declines since the mid 1970’s. These trends coincided with major changes in agricultural practices in lowland Britain, such as the switch from spring to autumn sowing of arable crops, and a shift away from crop rotations and mixed farming. The loss of winter stubbles and spring plough land, and the decline in the number of weedy fields from the use of herbicide has caused a rapid decrease in birds such as the skylark.
Between 1984 and 1990, there was a net loss of 23% of hedges in Britain, which is approximately 130,000 km or 81,000 miles. On average, one plant species per 10 metres of hedge was lost, which is an 8% loss of species.
The continuing loss and fragmentation of habitats such as chalk grassland, heather moor land, hay meadows and wetlands are a result of intensified farming practices, abstraction of water, development and road construction. Other habitats are lost through neglect.
Over the last 15 years, species diversity has fallen by an average of 14% in grassland and woodland habitats. As a result of the Common Agriculture Policy, the number of sheep in Wales increased by 30% between 1981 and 1991. Overgrazing has led to the decline of birds such as the corncrake and corn bunting, damage to 44,000 hectares (59%) of SSSI's, and failure of regeneration of Welsh broadleaved woodlands. Drainage has resulted in the loss or degradation of all of the wetlands in Wales over the last 50 years. As a consequence of more intense drainage since 1980, curlew numbers have fallen by 13%, snipe by 60% and redshank by 60%.