Identification

Title

2011 Scottish Natural Heritage (SNH) Scotland Didemnun vexillum records

Abstract

The carpet sea squirt (Didemnum vexillum) is an invasive non-native species of colonial sea squirt that has recently been found in England, Ireland, Wales and at one location in the Clyde, on the west coast of Scotland. The potential ecological and economic impacts of this species are significant. A rapid response eradication programme in Holyhead Harbour is currently underway, showing signs of some success so far. However, it is not known how far this species has spread within the UK, and surveys are underway in England and Wales to determine its distribution. It is crucial to know as soon as possible how far it has spread, as this information will determine what the appropriate response will be - if it is confined to only a few sites, it may be possible to attempt eradication. If it is already more widespread, then containment or control measures will be more appropriate. No specific surveys targeting this species had previously been carried out in Scotland, so it was not known whether it was present just in the one marina in the Clyde or whether it was more widespread. This project involved a series of rapid assessment surveys of those marinas and harbours thought to be most likely at risk from establishment (e.g. those in the Clyde and on the west coast of Scotland) and will inform SNH’s policy for dealing with this species, as well as the wider UK policy for response.

Resource type

dataset

Resource locator

http://www.dassh.ac.uk/geoserver/dbossh/ows?service=WFS&version=1.0.0&request=GetFeature&typeName=dbossh:fullview&outputFormat=csv&&CQL_FILTER=surveycode=%27DASSHDT00000150%27

name: Click to get data

description: A link to the web service or dataset

http://www.dassh.ac.uk

name: DASSH homepage

description: A link to the general host site

Unique resource identifier

code

DASSHDT00000150

codeSpace

http://www.dassh.ac.uk

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

urn:ogc:def:crs:EPSG::4326

Classification of spatial data and services

Topic category

biota

Keywords

Keyword set

keyword value

Keyword set

keyword value

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

revision

effective date

2008-01-06

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

revision

effective date

2009-11-16

Geographic location

West bounding longitude

-4.8627

East bounding longitude

-4.8540

North bounding latitude

55.7773

South bounding latitude

55.7717

Extent

Extent group

authority code

title

reference date

date type

creation

effective date

2009-06-18

code identifying the extent

Minches & Western Scotland

Extent group

authority code

title

reference date

date type

revision

effective date

2010-01-01

code identifying the extent

infralittoral

Extent group

authority code

title

reference date

date type

revision

effective date

2010-01-01

code identifying the extent

littoral

Extent group

authority code

title

reference date

date type

creation

effective date

2014-05-16

code identifying the extent

VIa

Temporal reference

Temporal extent

Begin position

2009-11-01

End position

2009-11-30

Dataset reference date

date type

publication

effective date

2016-02-22

Frequency of update

notPlanned

Quality and validity

Lineage

Part of MSFD NNS baseline data collation project (Jan 2016). Subset of a dataset as we were only pulling out records for a selection of INNS. Contains records for Didemnum vexillum. A methodical search of pontoon floats, anchor chains, pilings and any ropes or other items hanging into the water at each location was carried out for signs of D. vexillum by three researchers from the Scottish Association for Marine Science (SAMS). All the pontoons in the marina were inspected using viewing scopes and an underwater camera system operated from the pontoon walkway to collect video (Panasonic Optio W30 camera mounted on 2 m pole) and stills (Panasonic Optio W60 camera). Scrapers with fine mesh nets attached were also used to collect any suspect organisms for closer inspection. Surveys typically lasted between one and two hours depending on the size of the marina or harbour. The most effective survey method was for the group of researchers to stay together, with one person allocated to each of the side pontoons and the third person looking at the main walkway. This allowed instant confirmation by the survey team of any potential sightings of D. vexillum. Any additional non-native species found during the survey were recorded. Weather conditions and visibility of the water column was noted at each location. All the equipment was cleaned with sanitiser and the nets on each scraper changed between locations. Samples requiring verification were collected and preserved in alcohol for later inspection under a stereomicroscope.

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Public, however, whilst marina names may be determined from coordinates they may not be reported further

Constraint set

Limitations on public access

Public, however, whilst marina names may be determined from coordinates they may not be reported further

Responsible organisations

Responsible party

contact position

Ecologist

organisation name

Scottish Natural Heritage (SNH), Headquaters

full postal address

Great Glen House, Leachkin Road

Inverness

IV3 8NW

telephone number

01463 725000

email address

dassh.enquiries@mba.ac.uk

responsible party role

originator

Responsible party

contact position

Data Manager

organisation name

Data Archive for Seabed Species and Habitats (DASSH)

full postal address

Marine Biological Association of the UK, The Laboratory, Citadel Hill

Plymouth

PL1 2PB

telephone number

01752 633102

facsimile number

01752 633291

email address

dassh.enquiries@mba.ac.uk

responsible party role

custodian

Metadata on metadata

Metadata point of contact

organisation name

DASSH, The Archive for Marine Species and Habitat Data

email address

matarn@mba.ac.uk

responsible party role

pointOfContact

Metadata date

2018-01-15

Metadata language