Findings of drop down video and stills imagery from an area of drumlins off Northwest Anglesey, July 2019

This data contains the raw products of a seabed survey of an area of drumlins off north west Anglesey. The images and video was taken by a Natural Resources Wales owned drop down camera system to provide a better understanding of the seabed structure and biological communities at the survey sites and to investigate the presence of non-native species. The data contains Video (.asf) (and still images (.JPG) The data was collected on the 11th July 2019. The a copy of the MR snapshot produced after data analysis by the contractor is also supplied here. The analysis of the video and stills imagery followed guidelines provided by NRW, Marine EcoSol’s in-house standard operating procedures, and JNCC/NMBAQC recommendations. The video camera showed a swath of seabed approximately 0.3m wide, while still images showed an area estimated as about 0.13m2. All images were reviewed using appropriate high-quality imaging equipment capable of playing and displaying full HD video at 1920p x 1080p resolution.

The video and set of stills from each tow were reviewed prior to detailed assessment and recording, and the boundaries between biotopes or biotope complexes noted by recording the time and positional coordinates at which major changes in seabed and habitat type occurred. The species and substratum in each habitat ‘sample’ (tow section) was then recorded, and biotopes assigned. Discrete habitat tow sections or ‘samples’ as defined above were determined using a combination of video and stills images. The lower quality video imagery was then linked to the ‘sample’ in terms of data recording using the time stamp on the video playback. Higher quality stills images were used to identify and quantify substrates and taxa, with abundances pooled to assess the abundance of the taxa over each sample.

Identifier: NRW_DS125640

Metadata Language: English

Lineage: The images and video was taken by a Natural Resources Wales owned high definition camera drop down camera system from the survey vessel Mersey Guardian. It was deployed at a total of nine locations situated between 5km and 20km off the north west coast of Anglesey in an area of drumlin fields. Individual tows ranged from 319m to 864m in length most being between 500m and 700m. Depths ranged from 43m to 65m. Over two hours of video footage were collected together with 998 usable still images. Tow speeds ranged from 0.2knots up to 2.6knots, the faster speeds resulting in poor quality video imagery. In general stills image quality was good. All data were entered into Marine Recorder v5.7 under the Marine Recorder survey name ‘2019 Draft NRW Northwest Anglesey Drumlin Survey’. Each tow was a survey event, each habitat section a ‘sample’.

Additional Information: Baldock, L., Morris-Webb, L. 2020. Report on findings of drop down video and stills imagery from an area of drumlins off Northwest Anglesey, July 2019. NRW Evidence Report No: 401, 26pp, Natural Resources Wales, Bangor.

Dataset Reference Date (Publication): 2023-07-03

Temporal Extent

Begin date: 2019-07-11

End date: 2019-07-11

Topic category

Biota

Owner

Natural Resources Wales (NRW)

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

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

Originator

Natural Resources Wales (NRW)

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

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

Extent

Geographic Extent: Irish Sea

Vertical Extent

Medin Extent Keyword: circalittoral

Vertical Extent

Minimum value (metres): 43

Maximum value (metres): 65

Vertical CRS: urn:ogc:def:datum:EPSG::5100 Sea Level depth is unadjusted and does not take into account tidal height

Distribution

Format Type and Description

Image ( )

Specification

It showed a swath of seabed approximately 0.3m wide on the seabed. Image: Still images (998) in .JPG format. Database: The MR Snapshot (.dbf) produced by the contractor after analysis of the images and video as part of the contract
Movie ( )

Specification

Video files in Advances Systems Format (.asf) of each tow carried out. It showed a swath of seabed approximately 0.3m wide on the seabed. Image: Still images (998) in .JPG format. Database: The MR Snapshot (.dbf) produced by the contractor after analysis of the images and video as part of the contract
Documents ( )

Specification

NRW Evidence Report available in pdf or word format.

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: The images and video was taken by a Natural Resources Wales owned high definition camera drop down camera system from the survey vessel Mersey Guardian. It was deployed at a total of nine locations situated between 5km and 20km off the north west coast of Anglesey in an area of drumlin fields. Individual tows ranged from 319m to 864m in length most being between 500m and 700m. Depths ranged from 43m to 65m. Over two hours of video footage were collected together with 998 usable still images. Tow speeds ranged from 0.2knots up to 2.6knots, the faster speeds resulting in poor quality video imagery. In general stills image quality was good. All data were entered into Marine Recorder v5.7 under the Marine Recorder survey name ‘2019 Draft NRW Northwest Anglesey Drumlin Survey’. Each tow was a survey event, each habitat section a ‘sample’.

Keywords

GEMET - INSPIRE themes, version 1.0

Habitats and biotopes

Type: Theme

Citation

Date (Publication): 2008-06-01

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

Keywords

NRW Thesaurus

towed video
Drumlins

Type: Theme

Citation

Date (Publication): 2025-01-08

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

Keywords

SeaDataNet Parameter Discovery Vocabulary

Habitat extent
Habitat characterisation
Seabed photography

Type: Theme

Citation

Date (Publication): 2024-06-19

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

Code: Latitude and Longitude (EPSG::4326)

Content Information

NRW Profile

Custom Elements

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 on 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 ensur

Attribution Statement

Licence

Other constraints: Open Government Licence

Metadata

File Identifier: 4f4c4942-4343-5764-6473-313235363430 XML

Metadata Language: English

Resource type: Dataset

Metadata Date: 2025-02-21T09:47:31.476Z

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.

Findings of drop down video and stills imagery from an area of drumlins off Northwest Anglesey, July 2019

Identification

Temporal Extent

Extent

Extent

Vertical Extent

Vertical Extent

Distribution

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

Attribution Statement

Licence

Metadata

Metadata

Publishing Body