Llyn Tegid Hydroacoustic Surveys (2014)

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 undertaken in 2014 to carry out a hydroacoustic survey and measurement of environmental variables. The purpose of this data capture was to assess the status of gwyniad and its habitat in Llyn Tegid.

Identification

Identifier
NRW_DS115866
Alternative Title
  • Arolwg Hydroacwstig Llyn Tegid (2014)
Metadata Language
English
Lineage

Carried out hydroacoustic survey and the measurement of associated environmental variables (temperature and oxygen profiles, and secchi disk reading). Utilised standardised survey and monitoring protocol for the assessment of whitefish, 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 2.0 meters per section was adopted as general target mean speed rather than an absolute upper limit. The objectives of the present project were to collect and analyse hydroacoustic survey and associated environmental data during the summer of 2014, to interpret them with respect to similar data from earlier years, and to consider their implications for the current status of the gwyniad and its habitat in Llyn Tegid.
Dataset Reference Date (Publication)
2015-01-31
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

Extent

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


 
 

Distribution

Format Type and Description
  • Documents ()

    Specification

    Archive Project Number 227 Media 1519 [A] A report in .doc and .pdf format [B] Echoview Data Supplied as Comma Separated Value format files (*.csv). August 2014 [C] Oxygen profiles, temperature profiles in .xls format [D] Visual acquisition raw data (*.dt4 format) derived from the echo sounder Visual Acquisition Version 5.0.4 - proprietary software would be required to view or analyse this data. [E] Species abundance in .xls format. This will also be entered into Recorder 6

 

Quality

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

This dataset has not been assessed for conformance to the referenced INSPIRE regulation.
Degree
false
Lineage

Carried out hydroacoustic survey and the measurement of associated environmental variables (temperature and oxygen profiles, and secchi disk reading). Utilised standardised survey and monitoring protocol for the assessment of whitefish, 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 2.0 meters per section was adopted as general target mean speed rather than an absolute upper limit. The objectives of the present project were to collect and analyse hydroacoustic survey and associated environmental data during the summer of 2014, to interpret them with respect to similar data from earlier years, and to consider their implications for the current status of the gwyniad and its habitat in Llyn Tegid.
 

Keywords

Keywords

GEMET - INSPIRE themes, version 1.0
Type
Theme

Citation

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

Keywords

NRW Thesaurus
  • Llyn Tegid
  • gwyniad (freshwater whitefish)
  • coregonus lavaretus
  • hydroacoustic
  • marine and freshwater inventory
  • sechi disc
  • oxygen profile
  • temperature profile
Type
Theme

Citation

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

Spatial Reference System

Code
British National Grid (EPSG::27700)
 

Content

Content Information

NRW Profile

Custom Elements

NRW Related Title

Llyn Tegid hydroacoustic survey 2014
 

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

Use Constraints

Use constraints type
Other restrictions
Other constraints

© CNC/NRW Data may be re-used under the terms of the Open Government Licence providing it is done so, acknowledging both the source and NRW's copyright. It is the recipient's responsibility to ensure the data is fit for the intended purpose.
 
 
 

Metadata

Metadata

File Identifier
4f4c4942-4343-5764-6473-313135383636 XML
Metadata Language
English
Parent Identifier
Llyn Tegid Hydroacoustic Surveys and Gwyniad Translocations 2004-2009

NRW_DS101834
Resource type
Dataset
Metadata Date
2025-03-07T17:24:14.187Z
Metadata Standard Name
NRW
Metadata Standard Version

1.0

pointOfContact
  Natural Resources Wales (NRW)
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
 
 

Publishing Body

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