Field identification of habitats directive Annex I habitats as a major European biodiversity indicator

Annex I of the EU Habitats Directive lists the habitats which must be protected by the designation and management of protected areas in the European Union. These habitats are therefore a key indicator of biodiversity and although organised into nine groups, there is no way to identify them other than by gaining familiarity with the list. It is therefore necessary for observers who do not have sufficient experience to have a system to guide them into an appropriate class when in the field. A key has therefore been produced based on defined habitat categories that can be recorded consistently in the field in order to restrict the range of options for any given habitat patch. Expert judgement may still be needed to finalise the allocation to a specific class. A direct key is not possible because the list of Annex I habitats has been produced by meetings of national experts and final allocation often requires scientific judgement. A rule based system for Annex I habitats has therefore been designed to aid identification of the classes and to promote consistent interpretation between Member States. It is intended that in due course that the descriptions will be further developed from other data sources and by consultation with local experts. The first stage is to record a defined list of habitat categories in the field according to a series of rules. In the second stage a structure is provided to identify Annex I habitats that are landscape units or habitat complexes. In the third stage the recorded habitat categories are used to provide a structure to identify other classes using moisture and acidity levels as the primary filter. All Annex I habitats are characterised by summary data, including indicator species and geographical distribution. The system has been tested in the field throughout Europe and is available for field computers under Windows Mobile in order to enable ready access and encourage consistency.