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

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.

Identification

Identifier
NRW_DS121548
Alternative Title
Metadata Language
English
Lineage

Surveys were by visual searches and the collection of vegetation samples.
Additional Information

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.
Dataset Reference Date (Publication)
2018-01-01

Temporal Extent

Begin date
2017-10-16
End date
2017-10-17
 
Topic category
  • Biota
Owner
  Natural Resources Wales (NRW) -
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
Originator
  Willing -
C/O Natural Resources Wales
http://naturalresources.wales/?lang=en
 

Extent

Extent

Geographic Extent
Wales (WLS)
N
W
E
S
Map representing the geographic extent of the dataset


 
 

Distribution

Distribution

Format Type and Description
  • Database ( Unknown )

    Specification

    Species records held on Welsh Invertebrate Database

  • Documents ( Unknown )

    Specification

    Report as pdf format

 

Quality

Data quality

Quality Scope
Dataset
Conformity
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
Explanation

This dataset has not been assessed for conformance to the referenced INSPIRE regulation.
Degree
false
Lineage

Surveys were by visual searches and the collection of vegetation samples.
 

Keywords

Keywords

GEMET - INSPIRE themes, version 1.0
Type
Theme

Citation

Date (Publication)
2008-06-01
Code
geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme

Keywords

NRW Thesaurus
  • Desmoulin's whorl snail
  • vertigo moulinsiana
  • whorl snails
  • ecological surveys
  • entomological survey
  • biological monitoring
  • biological surveys
Type
Theme

Citation

Date (Publication)
2026-08-27
Code
geonetwork.thesaurus.local.theme.converted_nrw-keywords
 

Spatial Reference System

Code
British National Grid (EPSG::27700)
 

Content

Content Information

NRW Profile

Custom Elements

NRW Related Title

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
 

Constraints

Constraints

Limitations on Public Access and Use

Restriction type
Other restrictions
 

Access Constraints Directive

Limitations
no limitations
 

Access Constraints Text

Other constraints

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

© 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.
 

Attribution Statement

Other constraints

Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved.
 

Licence

Other constraints
Open Government Licence
 
 
 

Metadata

Metadata

File Identifier
4f4c4942-4343-5764-6473-313231353438 XML
Metadata Language
English
Parent Identifier
Welsh Invertebrate Database (WID)

NRW_DS23774
Resource type
Dataset
Metadata Date
2026-10-07T12:34:03.597Z
Metadata Standard Name
NRW
Metadata Standard Version

1.0

pointOfContact
  Natural Resources Wales (NRW) -
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
 
 

Publishing Body

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