Llyn Tegid and Llyn Arenig Fawr hydroacoustic and Gwyniad surveys 2012

  • English
  • wel
  • All

The gwyniad (Coregonus lavaretus) population of Llyn Tegid has been considered for a number of years to be threatened by deteriorating environmental conditions, especially those associated with eutrophication. This dataset contains the results of a project investigating the environmental variables. Attemps to translocate a population to Llyn Arenig Fawr have been attempted since 2003. The purpose of this data capture was to assess the status of gwyniad and its habitat in Llyn Tegid (native population) and Llyn Arenig Fawr (introduced population).

Identification

Dynodydd
Identifier
NRW_DS115217
Teitl Amgen
Alternative Title
  • Gwyniad Hydroacoustic and Gill Netting Survey of Llyn Arenig Fawr 2012- CCW Science Report 1013 CCW000800000000I
  • Gwyniad Hydroaccoustic Survey of Llyn Tegid 2012 - CCW Science Report 1012 CCW000800000000G
  • Arolygon hydroacwstig ac arolygon o wyniaid Llyn Tegid a Llyn Arenig Fawr 2012
Laith Metadata
Metadata Language
English
Lineage

At Llyn Tegid hydroacoustic surveys and the measurement of associated environmental variables (temperature and oxygen profiles, and secchi disk reading) were conducted. Utilised standardised survey and monitoring protocol for the assessment of whitefish (Bean, 2003, JNCC, 2005) with two minor deviations- rather than using the target strength to fish length relationship of Foote (1987) the relationship given by Love (1971) was used to allow wider comparison. Secondly a vessel speed of 2.0ms-1 was adopted as general target mean speed rather then an absolute upper limit. The above data collection was also undertaken at Llyn Arenig Fawr including a standardised gill-net survey. This forms part of the continuation of Llyn Tegid Hydroacoustic Surveys and Gwyniad Translocations 2004-2009 Project.
Additional Information

Team Leader Freshwater Ecosystems, NRW Ffynnon Reference Number: DCT-13-068971 / DCT-13-068914 Llyn Tegid Hydroacoustic Survey 2012 I. Winfield., J. Fletcher., and J. James., CCW Contract Science Report No. 1012 Ffynnon Reference Number: DCT-13-068851 / DCT-13-069046 Llyn Arenig Fawr Gwyniad Survey 2012 Winfield., J. Fletcher., and J. James., CCW Contract Science Report No. 1013
Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
Dataset Reference Date (Publication)
2012-08-07
Perchennog
Owner
  Natural Resources Wales (NRW)
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
Cychwynnwr
Originator
  Centre for Ecology and Hydrology (CEH)
Environment Centre Wales, Deiniol Road, Bangor, Gwynedd, LL57 2UW, Wales
http://www.ceh.ac.uk/
 

Extent

Extent

Hyd
Geographic Extent
GWYNEDD - GWYNEDD
N
W
E
S
Map representing the geographic extent of the dataset


 

Vertical Extent

Medin Extent Keyword

water column
 
 

Distribution

Fformat - Math a Disgrifiad
Format Type and Description
  • Database ()

    Specification

    [A] The final report in Microsoft Word and Adobe PDF formats (Ffynnon Word Format DCT-13-068914, PDF Format DCT-13-068971, Word Format DCT-13-068851). [B] Echoview Data from the laboratory examination and analysis of output from the echo sounder and GPS used in the field (*.csv format). [C] Oxygen and temperature profiles in .xls spreadsheet format [D] Visual acquisition raw data derived from the echo sounder (*.dt4 format). [E] Species data in .xls format [F] Images in .jpg format [G] Species data is held in Recorder 6 - Gwyniad Hydroaccoustic Survey of Llyn Tegid 2012 - CCW Science Report 1012 CCW000800000000G - Gwyniad Hydroacoustic and Gill Netting Survey of Llyn Arenig Fawr 2012- CCW Science Report 1013 CCW000800000000I

 

Quality

Ansawdd Data
Data quality

Cwmpas Ansawdd
Quality Scope
Dataset
Dataset
Cydymffurfiad
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
Degree
false
Lineage

At Llyn Tegid hydroacoustic surveys and the measurement of associated environmental variables (temperature and oxygen profiles, and secchi disk reading) were conducted. Utilised standardised survey and monitoring protocol for the assessment of whitefish (Bean, 2003, JNCC, 2005) with two minor deviations- rather than using the target strength to fish length relationship of Foote (1987) the relationship given by Love (1971) was used to allow wider comparison. Secondly a vessel speed of 2.0ms-1 was adopted as general target mean speed rather then an absolute upper limit. The above data collection was also undertaken at Llyn Arenig Fawr including a standardised gill-net survey. This forms part of the continuation of Llyn Tegid Hydroacoustic Surveys and Gwyniad Translocations 2004-2009 Project.
 

Keywords

Allweddair
Keywords

GEMET - INSPIRE themes, version 1.0
Math
Type
Theme
Theme

Dyfyniad
Citation

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

Allweddair
Keywords

NRW Thesaurus
  • Llyn Tegid
  • Llyn Arenig Fawr
  • gwyniad (freshwater whitefish)
  • coregonus lavaretus
  • hydroacoustic
  • marine and freshwater inventory
  • secchi depth
  • oxygen profile
  • temperature profile
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2023-12-31
Code
geonetwork.thesaurus.local.theme.converted_nrw-keywords

Allweddair
Keywords

SeaDataNet Parameter Discovery Vocabulary
  • Fish taxonomy-related counts
  • Temperature of the water column
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Adolygu)
Date (Revision)
2021-01-06
Code
geonetwork.thesaurus.external.theme.rdf+xml
 

Spatial Reference System

Code
British National Grid (EPSG::27700)
 

Content

Gwybodaeth Cynnwys
Content Information

Proffil CNC
NRW Profile

Elfennau CNC
Custom Elements

NRW Related Title

Llyn Arenig Fawr Gwyniad survey 2009
NRW Related Title

Llyn Tegid hydroacoustic survey 2012
 

Constraints

Constraints

Limitations on Public Access and Use

Math o Gyfyngiad
Restriction type
Other restrictions
Other restrictions
 

Access Constraints Directive

Limitations
no limitations
 

Access Constraints Text

Other constraints

There are no access restrictions to this data. NRW may release, publish or disseminate it freely.
 

Use Constraints

Cyfyngiadau Defnyddio
Use constraints type
Other restrictions
Other restrictions
Other constraints

© CNC/NRW 2012. 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
File Identifier
4f4c4942-4343-5764-6473-313135323137 XML
Laith Metadata
Metadata Language
English
Parent Identifier
Freshwater Gwyniad (Coregonus lavaretus) Species Survey Data

NRW_DS116344
Math o adnodd
Resource type
Dataset
Dataset
Dyddiad Metadata
Metadata Date
2024-05-31T09:39:34.224Z
Enw Safonol Metadata
Metadata Standard Name
NRW
Fersiwn Metadata
Metadata Standard Version

1.0

Pwynt Cyswllt
pointOfContact
  Master Reference Data Team
Natural Resources Wales, Maes y Fynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW
http://naturalresourceswales.gov.uk/splash?orig=/
 
 

Publishing Body

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