SAC Monitoring: Twaite (Alosa fallax) and Allis (Alosa alosa) Shad egg survey of the River Usk (2010-2011)
The River Usk rises in the Black Mountain range in the west of the Brecon Beacons National Park and flows east and then south, to enter the Severn Estuary at Newport. The river is designated as a Special Area of Conservation (SAC) for several features, including salmon, lampreys and shads. Twaite (Alosa fallax) and allis (Alosa alosa) shad are anadromous members of the Family Clupeidae (Herring). In Britain, twaite shad is known to spawn in the Rivers Severn, Wye, Usk and Tywi. However, it is not certain whether a breeding population of allis shad still exists. The fomer 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 JNCC 'Common Standards Methodology Guidance for Freshwater Fauna' (2005) gives a target for the spawning distribution of shad. It states there should be 'no decline in spawning distribution' assessed by kick sampling during May and June. There are two main data sources of shad spawning in the River Usk. The Environment Agency Wales (EAW), now Natural Resources Wales recorded the presence or absence of shad eggs at a number of sites, from 1990 to 2005, although surveys have only been conducted annually since 2003.
- Identification
- Extent
- Distribution
- Quality
- Keywords
- Spatial Reference System
- Content
- Constraints
- Maintenance
- Metadata
Identification
- Identifier
- NRW_DS112727
- Alternative Title
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- Shad Egg Survey River Usk 2011 - CCW - Report no.11/8/3 CCW0008000000009
- Shad Egg Survey River Usk 2010 - CCW - Report no.10/8/1 CCW000280000000E
- Monitro ACA: Arolygu Wyau Gwangod (Alosa fallax) a Herlynod (Alosa alosa) yn Afon Wysg (2010-2011)
- Metadata Language
- English
- Lineage
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The data and report outlines the monitoring undertaken by former CCW and EAW staff on the spawning distribution of shad during the spawning seasons of 2010 and 2011. - 2010 Surveys and evidence of spawning was recorded from the 26th of May to 22nd of June. - 2011 Surveys and evidence of spawning was recorded from the 19th of May to 6th of July. Natural Resources Wales also hold records of visible shad spawning at one location (Usk Town, NGR SO374007) for 5 consecutive years from 1997 to 2001. The standard Hillman et al. (2003) methodology was amended to record the presence or absence of shad eggs only. 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 data: High - work carried out by qualified CCW monitoring staff.
- Additional Information
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Rivers Ecologist, NRW.
- Dataset Reference Date (Publication)
- 2012-01-31
Temporal Extent
- Begin date
- 2010-05-26
- End date
- 2011-07-06
- Topic category
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- Environment
- Biota
- Inland waters
Extent
Extent
- Geographic Extent
- Wales (WLS)
Vertical Extent
- Medin Extent Keyword
Distribution
- Format Type and Description
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Database
Database
()
- Specification
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[A] The final reports in Microsoft Word and Adobe PDF formats. [B] Raw data workbooks in excel format [C] A series of images held in JPEG Format [D] Species data is held in Recorder as CCW000280000000E (2010) and CCW0008000000009 (2011)
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Database
Database
()
Quality
Data quality
- Quality Scope
- Dataset
- Lineage
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The data and report outlines the monitoring undertaken by former CCW and EAW staff on the spawning distribution of shad during the spawning seasons of 2010 and 2011. - 2010 Surveys and evidence of spawning was recorded from the 26th of May to 22nd of June. - 2011 Surveys and evidence of spawning was recorded from the 19th of May to 6th of July. Natural Resources Wales also hold records of visible shad spawning at one location (Usk Town, NGR SO374007) for 5 consecutive years from 1997 to 2001. The standard Hillman et al. (2003) methodology was amended to record the presence or absence of shad eggs only. 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 data: High - work carried out by qualified CCW monitoring staff.
Keywords
Keywords
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NRW Thesaurus
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- alosa alosa
- alosa fallax
- Special Areas of Conservation (SAC) (see also Candidate Special Areas of Conservation cSAC)
- survey methods (survey techniques) (survey) (surveying)
- Eggs
- clupea harengus
- Countryside Council for Wales (CCW)
- Shad
- River Usk
- Clupeidae
- herring
- Type
- Theme
Citation
- Date (Publication)
- 2024-04-09
Spatial Reference System
Content
Content Information
NRW Profile
Custom Elements
- NRW Related Title
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River Usk shad egg survey 2011
- NRW Related Title
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River Usk shad egg survey 2010
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 to 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 2010 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
- 4f4c4942-4343-5764-6473-313132373237 XML
- Metadata Language
- English
- Parent Identifier
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Condition monitoring of Special Areas of Conservation (SACs) in Wales
NRW_DS110194
- Resource type
- Dataset
- Metadata Date
- 2024-05-31T09:43:11.379Z
- Metadata Standard Name
- NRW
- Metadata Standard Version
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1.0