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.

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

Temporal Extent

Begin date: 2014-08-26

End date: 2014-08-26

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

Format Type and Description

Documents 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

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: 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

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
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

Code: British National Grid (EPSG::27700)

Content Information

NRW Profile

Custom Elements

NRW Related Title: Llyn Tegid hydroacoustic survey 2014

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

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: 2024-05-31T09:39:37.469Z

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

Access the portal

Full access to the portal and metadata.

Llyn Tegid Hydroacoustic Surveys (2014)

Identification

Temporal Extent

Extent

Extent

Distribution

Quality

Data quality

Keywords

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