4f4c4942-4343-5764-6473-313231353438 English NRW_DS23774 Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en 2025-03-07T15:04:08.232Z NRW 1.0 wel British National Grid (EPSG::27700) Surveys for Desmoulin’s Whorl Snail Vertigo moulinsiana on Cors Geirch National Nature Reserve (NNR) / Sites of Special Scientific Interest (SSSI) and the Afon Penrhos floodplain and for Geyer's Whorl Snail Vertigo geyeri on Cors Geirch NNR in 2017 Surveys for Desmoulin’s Whorl Snail Vertigo moulinsiana on Cors Geirch National Nature Reserve (NNR) / Sites of Special Scientific Interest (SSSI) and the Afon Penrhos floodplain and for Geyer's Whorl Snail Vertigo geyeri on Cors Geirch NNR in 2017 Arolygon o Falwen Droellog Desmoulin Vertigo moulinsiana ar Warchodfa Natur Genedlaethol Cors Geirch (NNR) / Safleoedd o Ddiddordeb Gwyddonol Arbennig (SoDdGA) a gorlifdir Afon Penrhos ac ar gyfer Malwen Droellog Geyer Vertigo geyeri ar Warchodfa Natur Genedlaethol Cors Geirch yn 2017 2018-01-01 NRW_DS121548 A survey was undertaken in October 2017 to determine the eastern distribution limits of Desmoulin's Whorl Snail Vertigo moulinsiana on the Afon Penrhos floodplain following a previous survey covering the western part of the site in 2016. Virtually all potentially suitable habitat was surveyed. Although most new survey areas proved negative, an additional 0.5ha of V. moulinsiana habitat was identified, this being contiguous with the occupied habitat block lying to the immediate west surveyed in 2016. Areas of habitat not supporting the snail were judged to be too dry and/or too acidic to support the snail. It is calculated that the minimum total area of the Afon Penrhos floodplain occupied by V. moulinsiana is 11.07ha, with a possible maximum of 13.2ha if a number of adjoining but potentially suitable un-surveyed areas also support the snail. The Afon Penrhos population is not only the largest of three in Wales, but also probably one of the largest in mainland Britain. The significance of the population here is further enhanced by recent considerable population losses at several Special Areas of Conservation (SACs) in southern England and on the nearby Corsydd Llyn SAC (Cors Geirch National Nature Reserve (NNR) / Site of Special Scientific Interest (SSSI)). Now that the probable full extent of the population on Afon Penrhos is known, it is recommended that the site should be notified as a SSSI to reduce any risk of loss or damage due to changes in site management. A survey was undertaken in October 2017 to determine the eastern distribution limits of Desmoulin's Whorl Snail Vertigo moulinsiana on the Afon Penrhos floodplain following a previous survey covering the western part of the site in 2016. Virtually all potentially suitable habitat was surveyed. Although most new survey areas proved negative, an additional 0.5ha of V. moulinsiana habitat was identified, this being contiguous with the occupied habitat block lying to the immediate west surveyed in 2016. Areas of habitat not supporting the snail were judged to be too dry and/or too acidic to support the snail. It is calculated that the minimum total area of the Afon Penrhos floodplain occupied by V. moulinsiana is 11.07ha, with a possible maximum of 13.2ha if a number of adjoining but potentially suitable un-surveyed areas also support the snail. The Afon Penrhos population is not only the largest of three in Wales, but also probably one of the largest in mainland Britain. The significance of the population here is further enhanced by recent considerable population losses at several Special Areas of Conservation (SACs) in southern England and on the nearby Corsydd Llyn SAC (Cors Geirch National Nature Reserve (NNR) / Site of Special Scientific Interest (SSSI)). Now that the probable full extent of the population on Afon Penrhos is known, it is recommended that the site should be notified as a SSSI to reduce any risk of loss or damage due to changes in site management. Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Willing C/O Natural Resources Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Species distribution Habitats and biotopes Protected sites GEMET - INSPIRE themes, version 1.0 GEMET - INSPIRE themes, version 1.0 2008-06-01 geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme ecological surveys biological surveys biological monitoring entomological survey vertigo moulinsiana whorl snails Desmoulin's whorl snail NRW Thesaurus NRW Thesaurus 2023-12-31 geonetwork.thesaurus.local.theme.converted_nrw-keywords SeaDataNet Parameter Discovery Vocabulary SeaDataNet Parameter Discovery Vocabulary 2021-01-06 geonetwork.thesaurus.external.theme.rdf+xml Integrated Public Sector Vocabulary Integrated Public Sector Vocabulary 2013-04-03 geonetwork.thesaurus.external.theme.subjects NRW SMNR Vocabulary NRW SMNR Vocabulary 2023-12-27 geonetwork.thesaurus.local.theme.converted_nrw-smnr-keywords There are no access restrictions on this data. NRW may release, publish or disseminate it freely. no limitations © CNC/NRW Data may be re-used under the terms of the Open Government Licence providing it is done so, acknowledging both the source and NRW's copyright. It is the recipient's responsibility to ensure the data is fit for the intended purpose. English biota SeaVoX Vertical Co-ordinate Coverages SeaVoX Vertical Co-ordinate Coverages 2021-01-06 Wales (WLS) -5.777741 -2.608865 51.240829 53.513067 2017-10-16 2017-10-17 Willing, M.J. 2018. Surveys for Desmoulin’s Whorl Snail Vertigo moulinsiana on Cors Geirch NNR/SSSI and the Afon Penrhos floodplain & for Geyer’s Whorl Snail Vertigo geyeri on Cors Geirch NNR in 2017. NRW Evidence Report No. 258, 23pp, Natural Resources Wales, Bangor. Surveys for Desmoulin’s Whorl Snail Vertigo moulinsiana on Cors Geirch NNR/SSSI and the Afon Penrhos floodplain & for Geyer’s Whorl Snail Vertigo geyeri on Cors Geirch NNR in 2017 Database Database – records held in WID. Documents: pdf of the report in the DMS report archive. Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 This dataset has not been assessed for conformance to the referenced INSPIRE regulation. false Surveys were by visual searches and the collection of vegetation samples. Surveys were by visual searches and the collection of vegetation samples.