Survey of Invasive Non-Native Species (INNS) at Welsh dredge disposal sites: Milford Haven and the Severn Estuary 2018
Natural Resources Wales (NRW) contracted Marine Ecological Solutions Ltd. (Marine EcoSol) to analyse species and habitats surveyed in several dredge disposal sites around Wales (Milford Haven, the Severn Estuary, Swansea Bay Outer and Holyhead Deed), and undertake a data and literature review to discuss the potential for marine Invasive Non-Native Species (INNS) transfer via dredge disposal pathways. The purpose of the surveys was to obtain information to inform decision making to minimise further spread of non-native species from dredge disposal.
- Identification
- Extent
- Distribution
- Quality
- Keywords
- Spatial Reference System
- Content
- Constraints
- Maintenance
- Metadata
Identification
- Identifier
- NRW_DS122590
- Alternative Title
-
- NRW_INNS_dredge_disposal_survey_2018
- Metadata Language
- English
- Lineage
-
Towed underwater imagery was collected from dredge disposal sites Milford Haven 2 and 3 comprising video and stills. Grab and trawl samples were collected from Merkur Bouy, Cardiff Grounds and Newport. Marine EcoSol was contracted to analyse towed underwater imagery from the Milford Haven surveys. Video and stills imagery from Milford Haven were analysed for substrates and species (including any INNS), and their habitats classified using the JNCC Marine Habitat Classification system. Photographs of the epibenthic species collected from the Severn Estuary surveys were also re-checked for INNS. All data were entered Marine Recorder v5.4 under the survey name '2018 NRW INNS Dredge Disposal Survey'. Imagery was of varying quality, and small epibenthic trawks and grabs possibly insufficient to pick up the presence of INNS within dredge disposal sites. Methodological limitations are discussed within the associated report, Baldock et al. (2019).
- Additional Information
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See Baldock, L., Moore, A., Wray, B., Evans, S. and E. Morris-Webb. 2019. Survey of Invasive Non-Native Species (INNS) at Welsh dredge disposal sites: Milford Haven and the Severn Estuary 2018. NRW Report.
- Dataset Reference Date (Publication)
- 2018-09-05
Extent
Extent
- Geographic Extent
- Bridgwater Bay
- Geographic Extent
- Celtic Sea
- Geographic Extent
- Bristol Channel
- Geographic Extent
- Severn Estuary
))
Vertical Extent
- Medin Extent Keyword
-
circalittoral
Vertical Extent
- Minimum value (metres)
- 10.5
- Maximum value (metres)
- 76
- 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
-
-
Database
()
- Specification
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Database 2018 NRW INNS Dredge Disposal Survey MRCCW325 NBNData.mdb Documents Baldock et al 2018 Dredge disposal Invasive Non-Native Species (INNS) monitoring report.docx 2018 Dredge Disposal INNS proforma R2.xlsx 2018 INNS Grab & Trawl Survey proforma_R1.xlsx Image Photographs and still images of the seabed
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Database
()
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
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This dataset has not been assessed for conformance to the referenced INSPIRE regulation.
- Degree
- false
- Lineage
-
Towed underwater imagery was collected from dredge disposal sites Milford Haven 2 and 3 comprising video and stills. Grab and trawl samples were collected from Merkur Bouy, Cardiff Grounds and Newport. Marine EcoSol was contracted to analyse towed underwater imagery from the Milford Haven surveys. Video and stills imagery from Milford Haven were analysed for substrates and species (including any INNS), and their habitats classified using the JNCC Marine Habitat Classification system. Photographs of the epibenthic species collected from the Severn Estuary surveys were also re-checked for INNS. All data were entered Marine Recorder v5.4 under the survey name '2018 NRW INNS Dredge Disposal Survey'. Imagery was of varying quality, and small epibenthic trawks and grabs possibly insufficient to pick up the presence of INNS within dredge disposal sites. Methodological limitations are discussed within the associated report, Baldock et al. (2019).
Keywords
Keywords
- Type
- Theme
Citation
- Date (Publication)
- 2008-06-01
Keywords
- NRW Thesaurus
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- dredging
- slipper limpet
- crepidula fornicata
- Type
- Theme
Citation
- Date (Publication)
- 2023-12-31
Keywords
Spatial Reference System
Content
Content Information
NRW Profile
Custom Elements
Constraints
Constraints
Limitations on Public Access and Use
- Restriction type
- Other restrictions
Access Constraints Directive
- Limitations
- no limitations
Access Constraints Text
- Other constraints
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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
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© 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. Attribution statement: Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved.
Metadata
Metadata
- File Identifier
- 4f4c4942-4343-5764-6473-313232353930 XML
- Metadata Language
- English
- Resource type
- Dataset
- Metadata Date
- 2026-03-03T14:33:50.848Z
- Metadata Standard Name
- NRW
- Metadata Standard Version
-
1.0