Freshwater Shad Monitoring Data
The Rivers Wye, Usk and Tywi are designated as Special Areas of Conservation (SACs) 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. The River Wye, Usk and Tywi have been designated as a Special Area of Conservation (SAC) for shads and other features including salmon, lampreys and bullhead. However, it is not certain whether a breeding population of allis shad still exists. The former Countryside Council for Wales (CCW), 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 purpose of this data capture was to assist with the assessment of Favourable Conservation Status along the Wye, Usk and Tywi to supplement the main shad spawning distribution condition assessment for these rivers. This dataset comprises of a number of surveys entered into Recorder 6 which have been packaged for dissemination onto the NBN Atlas. Detailed information about each of the survey data can be found under their individual metadata entries.
- Identification
- Extent
- Distribution
- Quality
- Keywords
- Spatial Reference System
- Content
- Constraints
- Maintenance
- Metadata
Identification
- Identifier
- NRW_DS116346
- Alternative Title
-
- Data Monitro Gwangen Dŵr Croyw
- Metadata Language
- English
- Lineage
-
Environment Agency Wales (EAW) and Countryside Council for Wales (CCW), recorded shad egg survey data are available for the River Wye Usk and Tywi. A minimum of 10 kick samples were undertaken at each site with the number of eggs found in each kick recorded. If in total 10 shad eggs were recorded the survey was terminated. However, if less than 10 shad eggs were recorded the kick sampling continued either until over 10 eggs were found or a maximum of 25 kick samples had been undertaken. Confidence in this dataset is high.
- Additional Information
-
For further information see the survey metadata: - 107792 SAC Monitoring: Shad Monitoring data for Rivers Wye, Usk and Tywi (2006) - 112727 SAC Monitoring: Twaite (Alosa fallax) and Allis (Alosa alosa) Shad egg survey of the River Usk (2010-2011) - 114673 SAC Monitoring: Shad Egg Survey on the River Wye (2011) - 115312 SAC Monitoring: Afon Tywi Shad Egg Survey (2012) - 115294 SAC Monitoring: Shad Egg Survey River Usk and River Wye (2012)
- Dataset Reference Date (Publication)
- 2016-08-17
Extent
Extent
- Geographic Extent
- Wales (WLS)
))
Vertical Extent
- Medin Extent Keyword
Distribution
Distribution
- Format Type and Description
-
-
Database
()
- Specification
-
[A] Species data is held in Recorder 6. [B] This dataset is also available to download on the NBN Gateway - See Resource Locator
-
Database
()
- Resource Locator
-
View and Download Data
World Wide Web page
Quality
Data quality
- Quality Scope
- Dataset
- Lineage
-
Environment Agency Wales (EAW) and Countryside Council for Wales (CCW), recorded shad egg survey data are available for the River Wye Usk and Tywi. A minimum of 10 kick samples were undertaken at each site with the number of eggs found in each kick recorded. If in total 10 shad eggs were recorded the survey was terminated. However, if less than 10 shad eggs were recorded the kick sampling continued either until over 10 eggs were found or a maximum of 25 kick samples had been undertaken. Confidence in this dataset is high.
Keywords
Keywords
-
NRW Thesaurus
-
- Special Areas of Conservation (SAC) (see also Candidate Special Areas of Conservation cSAC)
- Shad
- NBN Atlas
- National Biodiversity Network [NBN]
- alosa alosa
- twaite shad
- River Usk
- Special Areas of Conservation (SAC) - SAC monitoring
- alosa fallax
- allis shad
- Type
- Theme
Citation
- Date (Publication)
- 2024-04-09
Keywords
-
NRW SMNR Keywords
-
- Sustainable Management of Natural Resources (SMNR)
- Animals, Plants and Other Organisms (SMNR)
- Ecosystem (SMNR)
- Water Quality (SMNR)
- Management Areas (SMNR)
- Natural Resources (Incl. Features and Processes) (SMNR)
- Freshwater and Wetlands (SMNR)
- Type
- Theme
Citation
- Date (Publication)
- 2024-03-05
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
-
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 2011 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
- File Identifier
- 4f4c4942-4343-5764-6473-313136333436 XML
- Metadata Language
- English
- Parent Identifier
-
Natural Resources Wales (NRW) Species Data on the NBN Atlas
NRW_DS116805
- Resource type
- Dataset
- Metadata Date
- 2024-05-31T09:38:49.457Z
- Metadata Standard Name
- NRW
- Metadata Standard Version
-
1.0