NDFF Molluscs in EU Habitats Directive

The data about policy-relevant molluscs in the Habitats Directive of the European Commission: Narrow-mouthed whorl snail Desmoulin's whorl snail Lesser ramshorn snail are collected as part of the HabSlak project of the Anemoon Foundation (the Wijngaarslak and the Bataafse stroommossel − which are also mentioned in the Habitats Directive − are not included in this project) The HabSlak project is part of the Dutch Molluscs Atlas Project (ANM), but has a far more structured approach to supervising volunteers, a more systematic inventory method and a more stringent validation protocol. A standardised method has been used for inventory surveys of the 3 species since the first ͚catch-up͛ on occurrence research in 2004. Although the method has generally remained the same, changes and improvements have been made on a more detailed level based on newly acquired ecological knowledge. This method, which includes new information up to August 2009, is described in Boesveld et al. (2009). All species reported for the HabSlak project are checked by an expert from the Anemoon Foundation. Observations that are not checked by an expert are not included in the database. Observations without evidence are not accepted. Dataset available via https://www.ndff.nl/english / [e-mail] Positive observations without zeros.