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
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.
- Dull adnabod
- Rhychwant
- Dosbarthiad
- Ansawdd
- Allweddeiriau
- System Cyfeirio Gofodol
- Cynnwys
- Cyfyngiadau
- Cynnal a chadw
- Metadata
Dull adnabod
- Dynodydd
- NRW_DS121548
- Teitl Amgen
-
- Laith Metadata
- English
- Datganiad
-
Surveys were by visual searches and the collection of vegetation samples.
- Gwybodaeth ychwanegol
-
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.
- Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
- 2018-01-01
Ystod amser
- Dyddiad cychwyn
- 2017-10-16
- Dyddiad gorffen
- 2017-10-17
- Categori pwnc
-
- Biota
Rhychwant
Rhychwant
- Hyd
- Wales (WLS)
))
Dosbarthiad
Dosbarthiad
- Fformat - Math a Disgrifiad
-
-
Database
(
Unknown
)
- Math
-
Species records held on Welsh Invertebrate Database
-
Documents
(
Unknown
)
- Math
-
Report as pdf format
-
Database
(
Unknown
)
Ansawdd
Ansawdd Data
- Cwmpas Ansawdd
- Dataset
- Cydymffurfiad
- 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
- Eglurhad
-
This dataset has not been assessed for conformance to the referenced INSPIRE regulation.
- Gradd
- false
- Datganiad
-
Surveys were by visual searches and the collection of vegetation samples.
Allweddeiriau
Allweddair
- Math
- Theme
Dyfyniad
- Dyddiad (Cyhoeddiad)
- 2008-06-01
Allweddair
-
NRW Thesaurus
-
- Desmoulin's whorl snail
- vertigo moulinsiana
- whorl snails
- ecological surveys
- entomological survey
- biological monitoring
- biological surveys
- Math
- Theme
Dyfyniad
- Dyddiad (Cyhoeddiad)
- 2026-08-27
System Cyfeirio Gofodol
Cynnwys
Gwybodaeth Cynnwys
Proffil CNC
Elfennau CNC
- Teitlau cysylltiedig CNC
-
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
Cyfyngiadau
Cyfyngiadau
Cyfyngiadau ar Fynediad a Defnydd Cyhoeddus
- Math o Gyfyngiad
- Other restrictions
Cyfarwyddeb Cyfyngiadau Mynediad
- Cyfyngiadau
- no limitations
Testun cyfyngiadau mynediad
- Cyfyngiadau eraill
-
There are no access restrictions on this data. NRW may release, publish or disseminate it freely.
Defnyddiwch gyfyngiadau
- Cyfyngiadau Defnyddio
- Other restrictions
- Cyfyngiadau eraill
-
© 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.
Datganiad Priodoli
- Cyfyngiadau eraill
-
Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved.
Math o Drwydded
- Cyfyngiadau eraill
- Open Government Licence
Metadata
Metadata
- Dynodydd Ffeil
- 4f4c4942-4343-5764-6473-313231353438 XML
- Laith Metadata
- English
- Dynodydd Rhiant
-
Welsh Invertebrate Database (WID)
NRW_DS23774
- Math o adnodd
- Dataset
- Dyddiad Metadata
- 2026-10-07T12:34:03.597Z
- Enw Safonol Metadata
- NRW
- Fersiwn Metadata
-
1.0