Survey of distribution and extent of Didemnum vexillum in Holyhead Harbour after Storm Emma October 2018

  • English
  • wel
  • All

This dataset details the presence and absence of Didemnun vexillum (an invasive non-native Carpet Sea Squirt) around North West Anglesey after March 2018, when Storm Emma destroyed Holyhead marina. Live Didemnum vexillum, previously found to be established on the marina structures and nearby boat hulls and moorings, was presumed to be distributed on marina debris around NW Anglesey. Shore and diving surveys were conducted in October 2018 in the marina area and where the bulk of floating material was washed ashore on the NW of Anglesey coast early in March 2018. D vexillum was only located on the various marina structures that survived the storm and on boat hulls and moorings in the areas where it had been found on previous surveys.

Identification

Dynodydd
Identifier
NRW_DS122967
Teitl Amgen
Alternative Title
  • Arolwg o ddosbarthiad a hyd a lled Didemnum vexillum yn Harbwr Caergybi ar ôl Storm Emma Hydref 2018
Laith Metadata
Metadata Language
English
Lineage

Intertidal areas were investigated on foot with particular care taken to inspect marina debris, underboulders, overhangs and shaded vertical surfaces where didemnids are most likely to occur. Subtidal structures and natural features investigated by diving, concentrating on the types of habitat where D vexillum had been found previously: vertical and overhanging shaded surfaces of floating pontoons, boats and mooring buoys and chains. Fixed man-made and natural habitats where didemnids are known to occur were also investigated including harbour walls, jetty pilings, rip-rap and naturally occurring boulders. The intertidal survey covered 9 areas on the NW coast of Anglesey plus Porth y Felin and Scimitar beach in Holyhead New Harbour. Diving surveys were carried out on 58 locations in the New and Old Harbour areas to include the remains of the marina, boats and moorings in the New Harbour and structures, walls, pilings and natural rocky features in the New and Old Harbours. Presence / Absence data was collected for any occurrence of D vexillum with notes made of approximate abundance and the notable presence of any other non-native species.
Additional Information

Holt, R.H.F. 2018. Didemnum vexillum: survey of distribution and extent in Holyhead Harbour after storm Emma, October 2018. NRW Evidence report no. 306.
Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
Dataset Reference Date (Publication)
2019-07-31
Perchennog
Owner
  Natural Resources Wales (NRW)
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
Cychwynnwr
Originator
  Cloud Base Productions Ltd.
Cloud Base Productions Ltd., Tan Hwfa, Llanllechid, Bangor, LL57 3LA
www.cloudbasepro.co.uk
 

Extent

Extent

Hyd
Geographic Extent
Wales (WLS)
N
W
E
S
Map representing the geographic extent of the dataset


 

Vertical Extent

Medin Extent Keyword

benthic boundary layer
 
 

Distribution

Fformat - Math a Disgrifiad
Format Type and Description
  • Database ()

    Specification

    [A] Digital versions of the contract report: Microsoft Word document; and an Adobe Portable Document Format version. [B] Excel spreadsheets with species presence absence data. [C] Photographs of habitats and species [D] Marine Recorder file.

 

Quality

Ansawdd Data
Data quality

Cwmpas Ansawdd
Quality Scope
Dataset
Dataset
Cydymffurfiad
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

Intertidal areas were investigated on foot with particular care taken to inspect marina debris, underboulders, overhangs and shaded vertical surfaces where didemnids are most likely to occur. Subtidal structures and natural features investigated by diving, concentrating on the types of habitat where D vexillum had been found previously: vertical and overhanging shaded surfaces of floating pontoons, boats and mooring buoys and chains. Fixed man-made and natural habitats where didemnids are known to occur were also investigated including harbour walls, jetty pilings, rip-rap and naturally occurring boulders. The intertidal survey covered 9 areas on the NW coast of Anglesey plus Porth y Felin and Scimitar beach in Holyhead New Harbour. Diving surveys were carried out on 58 locations in the New and Old Harbour areas to include the remains of the marina, boats and moorings in the New Harbour and structures, walls, pilings and natural rocky features in the New and Old Harbours. Presence / Absence data was collected for any occurrence of D vexillum with notes made of approximate abundance and the notable presence of any other non-native species.
 

Keywords

Allweddair
Keywords

GEMET - INSPIRE themes, version 1.0
Math
Type
Theme
Theme

Dyfyniad
Citation

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

Allweddair
Keywords

NRW Thesaurus
  • invasive species (alien species)
  • Invasive Non-Native Species (INNS)
  • Didemnum vexillum
  • colonial sea squirt
  • Holyhead
  • marinas and marine docks
Math
Type
Theme
Theme

Dyfyniad
Citation

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

Allweddair
Keywords

SeaDataNet Parameter Discovery Vocabulary
  • Man-made structures
  • Habitat characterisation
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Adolygu)
Date (Revision)
2021-01-06
Code
geonetwork.thesaurus.external.theme.rdf+xml
 

Spatial Reference System

Code
Latitude and Longitude (EPSG::4326)
 

Content

Gwybodaeth Cynnwys
Content Information

Proffil CNC
NRW Profile

Elfennau CNC
Custom Elements

 

Constraints

Constraints

Limitations on Public Access and Use

Math o Gyfyngiad
Restriction type
Other restrictions
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

Cyfyngiadau Defnyddio
Use constraints type
Other restrictions
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. Attribution statement: Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved.
 
 
 

Metadata

Metadata

Dynodydd Ffeil
File Identifier
4f4c4942-4343-5764-6473-313232393637 XML
Laith Metadata
Metadata Language
English
Math o adnodd
Resource type
Dataset
Dataset
Dyddiad Metadata
Metadata Date
2024-05-31T09:41:01.049Z
Enw Safonol Metadata
Metadata Standard Name
NRW
Fersiwn Metadata
Metadata Standard Version

1.0

Pwynt Cyswllt
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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