Upland heather moorland in Great Britain: A review of international importance, vegetation change and some objectives for nature conservation

This paper reviews the international significance of upland heather moorland, changes in its Great Britain (GB) extent, and some management and policy objectives for nature conservation. This sub-montane habitat is found mostly in the United Kingdom (UK) and Ireland, and along parts of the western seaboard of the northwest European mainland. There are 19 constituent plant communities (23% of total GB complement of upland communities) of which five are virtually confined to GB and a further six are better represented in GB than elsewhere. Of these, 13% are listed under the EC ‘Habitats Directive’ 92/43/EEC. Most communities are derived from woodland or scrub, and the complex successional changes in vegetation under different management practices are illustrated. The GB distribution of each community is summarised. The bird assemblage of 40 species contains a unique mixture characterised by internationally important populations, high breeding and/or foraging densities and zoogeographical outliers; eight species are listed under Annex 1 of the EC ‘Birds’ Directive 79/409/EEC. Around 20% of upland heather moorland present in England and Wales in the mid 1940s has changed under afforestation, agricultural reclamation, high grazing pressures and bracken Pteridium aquilinum invasion. Of that remaining, 70% is estimated to be at risk of change, with at least 50% in ‘poor’ or ‘suppressed’ condition liable to further reductions and damage under sheep Ovis aries grazing densities of >2 ewes ha −1. In Scotland, there has been a reduction by 18% in heather-dominated moorland (excluding blanket bog), between the 1940s and 1970s, with losses as high as 67% in some regions. Forty percent of the bird species' ranges and/or populations have declined since the early 1970s (mainly due to afforestation, persecution and heavy grazing pressure). National and regional objectives for the regeneration of upland heather moorland in GB are suggested. These include retaining cover of dwarf shrubs and bryophytes, and extending/enhancing the breeding distributions of at least six ‘flagship’ bird species. A new sustainable form of moorland management is described involving (a) changes in grouse moor management practices, and (b) the introduction of new grazing management prescriptions. Policy decisions announced recently by the UK Government relating to heather moorland conservation are summarised.