Llyn Tegid and Llyn Arenig Fawr hydroacoustic and Gwyniad surveys 2012

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).

Identifier: NRW_DS115217

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

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

Dataset Reference Date (Publication): 2012-08-07

Temporal Extent

Begin date: 2012-08-06

End date: 2012-08-07

Topic category

Biota

Owner

Natural Resources Wales (NRW)

Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales

http://naturalresources.wales/?lang=en

Originator

Centre for Ecology and Hydrology (CEH)

Environment Centre Wales, Deiniol Road, Bangor, Gwynedd, LL57 2UW, Wales

http://www.ceh.ac.uk/

Extent

Geographic Extent: GWYNEDD - GWYNEDD

Vertical Extent

Medin Extent Keyword: water column

Format Type and Description

Database 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

Data quality

Quality Scope: Dataset

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

GEMET - INSPIRE themes, version 1.0

Species distribution

Type: Theme

Citation

Date (Publication): 2008-06-01

Code: geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme

Keywords

NRW Thesaurus

Llyn Tegid
Llyn Arenig Fawr
gwyniad (freshwater whitefish)
coregonus lavaretus
hydroacoustic
marine and freshwater inventory
secchi depth
oxygen profile
temperature profile

Type: Theme

Citation

Date (Publication): 2023-12-31

Code: geonetwork.thesaurus.local.theme.converted_nrw-keywords

Keywords

SeaDataNet Parameter Discovery Vocabulary

Fish taxonomy-related counts
Temperature of the water column

Type: Theme

Citation

Date (Revision): 2021-01-06

Code: geonetwork.thesaurus.external.theme.rdf+xml

Code: British National Grid (EPSG::27700)

Content Information

NRW Profile

Custom Elements

NRW Related Title: Llyn Arenig Fawr Gwyniad survey 2009

NRW Related Title: Llyn Tegid hydroacoustic survey 2012

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 to this data. NRW may release, publish or disseminate it freely.

Use Constraints

Use constraints type: 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

File Identifier: 4f4c4942-4343-5764-6473-313135323137 XML

Metadata Language: English

Parent Identifier: Freshwater Gwyniad (Coregonus lavaretus) Species Survey Data
NRW_DS116344

Resource type: Dataset

Metadata Date: 2024-05-31T09:39:34.224Z

Metadata Standard Name: NRW

Metadata Standard Version: 1.0

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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Full access to the portal and metadata.

Llyn Tegid and Llyn Arenig Fawr hydroacoustic and Gwyniad surveys 2012

Identification

Temporal Extent

Extent

Extent

Vertical Extent

Distribution

Quality

Data quality

Keywords

Keywords

Citation

Keywords

Citation

Keywords

Citation

Spatial Reference System

Content

Content Information

NRW Profile

Custom Elements

Constraints

Constraints

Limitations on Public Access and Use

Access Constraints Directive

Access Constraints Text

Use Constraints

Metadata

Metadata

Publishing Body