The status of Desmoulin’s Whorl Snail (Vertigo moulinsiana) at Rhos Goch National Nature Reserve (NNR) (2015)
This dataset is made up of the results of a survey for Desmoulin’s Whorl Snail (Vertigo moulinsiana) in 2015, confirming it's presences at Rhos Goch National Nature Reserve (NNR) following it discovery at this location in 2007, making this one of only three sites in Wales for the snail. Desmoulin’s whorl snail Vertigo moulinsiana, despite being a small snail, is the largest Vertigo species, with a shell height up to about 2.6 mm. V. moulinsiana is only known from three localities in Wales; Cors Geirch and Afon Penrhos near Pwllheli on the Llŷn peninsula, and Rhos Goch National Nature Reserve near Hay-on-Wye in Radnorshire. All of the Welsh V. moulinsiana sites are isolated and do not closely resemble the lake and river-side base-rich fens typically associated with the snail at most of its English sites. The conservation importance of the species has meant its inclusion in various schedules and Red Data lists. It was categorised as Rare (category 3) in the UK Red Data Books, and more recently has been classed as Vulnerable in the recent IUCN-based UK Red List status review. The species is listed on Annex IIa of the European Community Habitats and Species Directive (92/43/EEC) and is also a Welsh Section 42 Species of Principal Importance (replacing the UK BAP priority species in 2006). The purpose of this data capture was to survey for V. moulinsiana, focussing on areas where there was known presence in 2007, and later a wider search for potentially suitable habitat within the NNR and adjoining Site of Special Scientific Interest (SSSI).
- Identification
- Extent
- Distribution
- Quality
- Keywords
- Spatial Reference System
- Content
- Constraints
- Maintenance
- Metadata
Identification
- Identifier
- NRW_DS116504
- Alternative Title
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- Statws y Falwen Droellog Desmoulin (Vertigo moulinsiana) yng Ngwarchodfa Natur Genedlaethol Rhos Goch (GNG) (2015)
- Metadata Language
- English
- Lineage
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Tray beating was undertaken in dry weather conditions, using a gridded white beating tray measuring approximately 25cm X 33cm was used. Tray beating is a well established technique of beating herbaceous fen vegetation onto a gridded white plastic tray. At selected locations, this allowed approximate V. moulinsiana numbers per unit area to be estimated (6 trays being approximately equivalent to 0.5 m2). In addition to this: - Dominant vegetation presence was recorded, noting particularly ‘+’ and ‘-‘ V. moulinsiana ‘suitability indicators’ (e.g. Carex sp, Glyceria maxima as ‘+’ indicators and Epilobium sp and Urtica dioica as ‘-‘); - Degree of site shading by overhead or over-hanging trees and bushes was recorded as a simple % canopy cover where appropriate, as shading can negatively affect the suitability of sites for V. moulinsiana; - Other potentially important site environmental and management details were recorded e.g. grazing and/or ground poaching, recent cutting, human trampling, pheasant release pens. Other mollusc species present were noted. At four locations, bulk samples of vegetation were removed (chiefly in the open fen area lying on the western margins of the site; - Where located V. moulinsiana numbers were counted per 6-tray samples and then converted into approximate numbers m-2 with numbers of adult and juvenile snails recorded separately. GPS 12 fig references and digital images were recorded for each main sample point. In addition to these, tray beating was carried out as the surveyor walked around the site to try and locate V. mulinsiana ‘pockets’ that might otherwise be overlooked.
- Additional Information
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Willing, M.J. 2016 The status of Desmoulin’s Whorl Snail Vertigo moulinsiana at Rhos Goch NNR in 2015. NRW Evidence Report No: 157, 20pp. Natural Resources Wales, Bangor.
- Dataset Reference Date (Publication)
- 2016-03-31
Temporal Extent
- Begin date
- 2015-10-21
- End date
- 2015-10-22
- Topic category
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- Biota
Extent
Extent
- Geographic Extent
- POWYS - POWYS
))
Distribution
- Format Type and Description
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Database
Database
()
- Specification
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[A] The final report in Microsoft Word and Adobe PDF formats. [B] Species records, which are held on the NRW Recorder 6 database.
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Database
Database
()
Quality
Data quality
- Quality Scope
- Dataset
- Lineage
-
Tray beating was undertaken in dry weather conditions, using a gridded white beating tray measuring approximately 25cm X 33cm was used. Tray beating is a well established technique of beating herbaceous fen vegetation onto a gridded white plastic tray. At selected locations, this allowed approximate V. moulinsiana numbers per unit area to be estimated (6 trays being approximately equivalent to 0.5 m2). In addition to this: - Dominant vegetation presence was recorded, noting particularly ‘+’ and ‘-‘ V. moulinsiana ‘suitability indicators’ (e.g. Carex sp, Glyceria maxima as ‘+’ indicators and Epilobium sp and Urtica dioica as ‘-‘); - Degree of site shading by overhead or over-hanging trees and bushes was recorded as a simple % canopy cover where appropriate, as shading can negatively affect the suitability of sites for V. moulinsiana; - Other potentially important site environmental and management details were recorded e.g. grazing and/or ground poaching, recent cutting, human trampling, pheasant release pens. Other mollusc species present were noted. At four locations, bulk samples of vegetation were removed (chiefly in the open fen area lying on the western margins of the site; - Where located V. moulinsiana numbers were counted per 6-tray samples and then converted into approximate numbers m-2 with numbers of adult and juvenile snails recorded separately. GPS 12 fig references and digital images were recorded for each main sample point. In addition to these, tray beating was carried out as the surveyor walked around the site to try and locate V. mulinsiana ‘pockets’ that might otherwise be overlooked.
Keywords
Keywords
- Type
- Theme
Citation
- Date (Publication)
- 2008-06-01
Keywords
- NRW Thesaurus
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- Desmoulin's whorl snail
- vertigo moulinsiana
- snails
- Rhos Goch
- Rhos Goch NNR
- Type
- Theme
Citation
- Date (Publication)
- 2023-12-31
Spatial Reference System
Content
Content Information
NRW Profile
Custom Elements
Constraints
Constraints
Limitations on Public Access and Use
- Restriction type
- Other restrictions
Access Constraints Directive
- Limitations
- no limitations
Access Constraints Text
- Other constraints
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There are no access restrictions on this data. NRW may release, publish or disseminate it freely.
Use Constraints
- Use constraints type
- Other restrictions
- Other constraints
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© 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.
Metadata
Metadata
- File Identifier
- 4f4c4942-4343-5764-6473-313136353034 XML
- Metadata Language
- English
- Parent Identifier
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Welsh Invertebrate Database (WID)
NRW_DS23774
- Resource type
- Dataset
- Metadata Date
- 2024-05-31T09:41:13.928Z
- Metadata Standard Name
- NRW
- Metadata Standard Version
-
1.0