A survey of the coverage, use and application of ancient woodland indicator lists in the UK

This report presents the results of a survey into the current use of ancient woodland indicator species lists in the UK. The idea of using species particularly vascular plants as indicators of ancient woodlands can be dated back to the 1970s and the work of Peterken. Since then a wide number of lists of Ancient Woodland Indicators (AWIs)have been produced, some based on expert opinions, some utilising field surveys, others adapted from existing lists. Recently developed lists, e.g. the lists for Scotland, Wales and Northern Ireland have been based on either robust reviews of existing lists, and/or expert opinion and/or field surveys and statistical analysis. Concerns however have been expressed regarding the use of lists and these concerns appear to be supported by the uncritical use of indicator species in recent planning inquiries, e.g. not recognising that indicators are indicators and considering them to be the key value of a woodland. A survey was undertaken of relevant individuals working in biological record centres, local authorities and key agencies across the UK. The survey sought to identify what lists of Ancient Woodland Indicators are currently in use, where possible to determine the methods used in developing these lists. The survey also sought to assess the awareness of ancient woodland indicator lists and review the ways in which these were used. A total of 419 questionnaires were sent out; a response rate of 11% was obtained. Follow up phone conversations were held with key individuals involved in developing ancient woodland indicator lists. Responses were received from all counties excluding: Buckinghamshire, Cheshire, Essex, Huntingdonshire, Middlesex, Northamptonshire, Staffordshire, Wiltshire and Worcestershire. In addition, the Lancashire respondent stated there was no AWI list for Lancashire. The key findings of the survey were: • There is a wide variety of lists of Ancient Woodland Indicators lists available covering most of the UK. • Most individuals using indicator lists are unaware of the methods used to produce the lists and therefore of their robustness. Some key stakeholders are unaware of the existence of indicator lists in their area. • Attitudes to ancient woodland indicator lists are variable, as is their use. • Few lists use species thresholds or weightings in determining whether a site is ancient, several lists are currently under review. • There are over 200 species listed on the various Ancient Woodland Indicators lists, few species are common to more than a quarter of the lists.