SAC Monitoring: Afon Tywi Shad Egg Survey (2012)
The Afon Tywi is designated as a Special Area of Conservation (SAC) under the EC 92/43/EEC Habitats Directive for several features including twaite shad (Alosa fallax) and allis shad (Alosa alosa). Shads are migratory members of the Clupeidae (herring family) that ascend rivers to spawn in late spring. The populations of both species are threatened in Europe mainly due to obstructions to migration and issues surrounding water quality. In the UK, significant populations of shad spawn in the Rivers Severn, Usk, Wye and Tywi. Former Countryside Council for Wales (CCW), Environment Agency Wales (EAW) and now Natural Resources Wales (NRW) is responsible for monitoring the condition of shad populations within SACs and to ensure the maintenance of favourable conservation status within these designated sites. The Joint Nature Conservation Committee (JNCC) published generic guidance on 'Common Standards Monitoring Guidance for Freshwater Fauna' (JNCC, 2005) outlining the attributes (mandatory and discretionary) and targets for monitoring freshwater fish. These include targets for shad population, river flow, water quality and river morphology. The purpose of this data collection was to facilitate the determination of Favourable Conservation status of Shad in the Afon Tywi. Confidence in this dataset is high, as survey were undertaken by experienced staff members.
- Dull adnabod
- Rhychwant
- Dosbarthiad
- Ansawdd
- Allweddeiriau
- System Cyfeirio Gofodol
- Cynnwys
- Cyfyngiadau
- Cynnal a chadw
- Metadata
Dull adnabod
- Dynodydd
- NRW_DS115312
- Teitl Amgen
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- Shad egg Survey Afon Tywi 2012 - CCW - Report No. 12/8/4 CCW000800000000P
- Monitro ACA: Arolygu Wyau Gwangod (Alosa fallax) a Herlynod (Alosa alosa) yn Afon Tywi (2012)
- Laith Metadata
- English
- Datganiad
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Countryside Council for Wales' (CCW) and Environment Agency Wales (EAW) staff monitored the spawning distribution of shads at 13 sample sites within 60 km of the main river corridor during the spawning season of 2012. The standard methodology was amended to reduce the sampling required at sites where shad eggs were present. This enabled the CSM target to be assessed and many more sites to be surveyed within the available time. The Hillman et al (2003) methodology was modified to a minimum of 10 kick samples were undertaken at each site with the number of eggs found in each kick recorded. If 10 or more shad eggs were recorded after 10 kicks the survey was terminated. However, if fewer than 10 shad eggs were recorded, kick sampling continued either until 10 eggs were found or 25 kick samples had been completed.
- Gwybodaeth ychwanegol
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Freshwater Monitoring Co-ordinator, NRW. Ffynnon Reference NRW-13-019708 Garrett, H.M., Thomas, Rh. & Hatton-Ellis, T.W. (2012). Afon Tywi SAC shad egg survey 2012. CCW Staff Science Report No. 12/8/4. 37pp, CCW. Bangor.
- Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
- 2013-05-31
Ystod amser
- Dyddiad cychwyn
- 2012-05-22
- Dyddiad gorffen
- 2012-05-29
- Categori pwnc
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- Biota
Rhychwant
Rhychwant
- Hyd
- SIR GAERFYRDDIN - CARMARTHENSHIRE
Dosbarthiad
- Fformat - Math a Disgrifiad
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Database
Database
()
- Math
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[A] Report in word and pdf format in Ffynnon (NRW-13-014651 / NRW-13-019708) [B] A set of survey site Photos in jpeg format (collated in Document DCT-12-229420) [C] A series of GIS layers in MapInfo .Tab format on which the maps are based [D] A set of spreadsheets for the raw data and worked up data in xls format (DCT-12-168511, DCT-12-181270, DCT-12-233511) [E] Field notes in paper format (held in in Llandeilo office. Copies held in MFEG, Maes y Ffynnon, Bangor) [F] Species data is held within Recorder as Shad egg Survey Afon Tywi 2012 - CCW - Report No. 12/8/4 CCW000800000000P.
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Database
Database
()
Ansawdd
Ansawdd Data
- Cwmpas Ansawdd
- Dataset
- Datganiad
-
Countryside Council for Wales' (CCW) and Environment Agency Wales (EAW) staff monitored the spawning distribution of shads at 13 sample sites within 60 km of the main river corridor during the spawning season of 2012. The standard methodology was amended to reduce the sampling required at sites where shad eggs were present. This enabled the CSM target to be assessed and many more sites to be surveyed within the available time. The Hillman et al (2003) methodology was modified to a minimum of 10 kick samples were undertaken at each site with the number of eggs found in each kick recorded. If 10 or more shad eggs were recorded after 10 kicks the survey was terminated. However, if fewer than 10 shad eggs were recorded, kick sampling continued either until 10 eggs were found or 25 kick samples had been completed.
Allweddeiriau
Allweddair
- Math
- Theme
Dyfyniad
- Dyddiad (Cyhoeddiad)
- 2008-06-01
Allweddair
- NRW Thesaurus
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- allis shad
- alosa alosa
- Shad
- twaite shad
- alosa fallax
- river Tywi (afon Tywi)
- Special Area of Conservation Monitoring
- Special Areas of Conservation (SAC) - SAC monitoring
- Math
- Theme
Dyfyniad
- Dyddiad (Cyhoeddiad)
- 2023-12-31
System Cyfeirio Gofodol
Cynnwys
Gwybodaeth Cynnwys
Proffil CNC
Elfennau CNC
- Teitlau cysylltiedig CNC
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Afon Tywi SAC shad egg survey 2012
Cyfyngiadau
Cyfyngiadau
Cyfyngiadau ar Fynediad a Defnydd Cyhoeddus
- Math o Gyfyngiad
- Other restrictions
Cyfarwyddeb Cyfyngiadau Mynediad
- Cyfyngiadau
- no limitations
Testun cyfyngiadau mynediad
- Cyfyngiadau eraill
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There are no access restrictions to this data. NRW may release, publish or disseminate it freely.
Defnyddiwch gyfyngiadau
- Cyfyngiadau Defnyddio
- Other restrictions
- Cyfyngiadau eraill
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© CNC/NRW 2013 There are no use restrictions on this data. Recipients may re-use, reproduce, disseminate this data free of charge in any format or medium, provided they do so accurately, acknowledging both the source and NRW's copyright, and do not use it in a misleading context. It is the recipient's responsibility to ensure the data is fit for the intended purpose, that dissemination or publishing does not result in duplication, and that it is fairly interpreted. Advice on interpretation should be sought where required. To avoid re-using old data, users should periodically obtain the latest version from the original source.
Metadata
Metadata
- Dynodydd Ffeil
- 4f4c4942-4343-5764-6473-313135333132 XML
- Laith Metadata
- English
- Dynodydd Rhiant
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Freshwater Shad Monitoring Data
NRW_DS116346
- Math o adnodd
- Dataset
- Dyddiad Metadata
- 2024-05-31T09:42:49.854Z
- Enw Safonol Metadata
- NRW
- Fersiwn Metadata
-
1.0