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Metadata: Modelling the Predicted Spread of a Carpet Sea Squirt ( Didemnum vexillum ) around the Welsh Coast (2011)
Abstract:
Didemnum vexillum is an invasive sea squirt that is not native to UK shores. It was first detected in Europe in 1991 and has since spread to several countries (including France, Ireland and the UK). The species has been located in Wales, Scotland and England and there is concern D. vexillum may have negative impacts on biodiversity and shellfish interests. Predicting the spread of an invasive species is crucial when assessing possible management actions. The potential impacts of the species on both biodiversity and commercial interests need to be studied and a cost-benefit approach taken to decide on the best course of management for that species. Geographic Information System (GIS) offers a fast, efficient way to map this predicted spread. The results of this mapping can then be used to focus on areas where D. vexillum may conflict with conservation and commercial interests.
Data holder:
Natural Resources Wales (NRW)
Click on the red button for resource contact details:
- Click on the red button for resource contact details
| Other details | ||
| Internal code | Internally assigned metadata identifier | 8755 |
| Title | The title is used to provide a brief and precise description of the dataset such as 'Date', 'Originating organisation/programme', 'Location' and 'Type of survey'. All acronyms and abbreviations should be reproduced in full. | Modelling the Predicted Spread of a Carpet Sea Squirt ( Didemnum vexillum ) around the Welsh Coast (2011) |
| File Identifier | The File Identifier is a code, preferably a GUID, that is globally unique and remains with the same metadata record even if the record is edited or transferred between portals or tools. | NRW_DS113445 |
| Resource Identifier | This is the code assigned by the data owner. | 4f4c4942-4343-5764-6473-313133343435 |
| Resource type | The resource type will likely be a dataset but could also be a series (collection of datasets with a common specification) or a service. | dataset |
| Start date | This describes the date the resource starts. This may only be the year if month and day are not known | 2009-01-01 |
| End date | This describes the date the resource ends. This may only be the year if month and day are not known | 2011-01-28 |
| Frequency of updates | This describes the frequency with which the resource is modified or updated i.e. a monitoring programme that samples once per year has a frequency that is described as 'annually'. | notPlanned |
| Abstract | The abstract provides a clear and brief statement of the content of the resource. | Didemnum vexillum is an invasive sea squirt that is not native to UK shores. It was first detected in Europe in 1991 and has since spread to several countries (including France, Ireland and the UK). The species has been located in Wales, Scotland and England and there is concern D. vexillum may have negative impacts on biodiversity and shellfish interests. Predicting the spread of an invasive species is crucial when assessing possible management actions. The potential impacts of the species on both biodiversity and commercial interests need to be studied and a cost-benefit approach taken to decide on the best course of management for that species. Geographic Information System (GIS) offers a fast, efficient way to map this predicted spread. The results of this mapping can then be used to focus on areas where D. vexillum may conflict with conservation and commercial interests. |
| Lineage | Lineage includes the background information, history of the sources of data, data quality statements and methods. | Countryside Council for Wales (CCW) has been investigating and controlling the spread of D. vexillum in Holyhead Marina since 2009. For this project, all the GIS spatial processing was carried out in ArcMAP 9.3 and used the ArcMAP toolbox along with Hawth's Tools and ET Geowizzards toolboxes. Data was used from 2009 - 2011 and a predictability model used which may have some limitations. In order to predict the potential spread of D. vexillum a simple modelling approach can be used, which uses the species biological limits and current known populations to estimate the positions of future colonies. Whilst this approach quickly produces results, it is limited as the model is not quantitative and can not be adequately tested. |
| Related keywords | ||
| Keyword | General subject area(s) associated with the resource, uses multiple controlled vocabularies | Species distribution |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | WALES | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | non-native species | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | Holyhead | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | invasive species (alien species) | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | colonial sea squirt | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | Didemnum vexillum | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | ascidians | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | marinas and marine docks | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | sea squirt | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | Salinity of the water column | |
| General subject area(s) associated with the resource, uses multiple controlled vocabularies | Temperature of the water column | |
| Geographical coverage | ||
| North | The northern-most limit of the data resource in decimal degrees | 53.55513005 |
| East | The eastern-most limit of the data resource in decimal degrees | -2.48898781 |
| South | The southern-most limit of the data resource in decimal degrees | 51.10318921 |
| West | The western-most limit of the data resource in decimal degrees | -5.6388218 |
| Regional sea | United Kingdom (UKM) | |
| Wales (WLS) | ||
| Responsible organisations | ||
| Role | The point of contact is person or organisation with responsibility for the creation and maintenance of the metadata for the resource. | pointOfContact |
| Organisation name | Natural Resources Wales (NRW) | |
| Delivery point | Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales | |
| enquiries@naturalresourceswales.gov.uk | ||
| URL | http://naturalresources.wales/?lang=en | |
| Role | The owner is the person or organisation that owns the resource. | owner |
| Organisation name | Natural Resources Wales (NRW) | |
| Delivery point | Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales | |
| enquiries@naturalresourceswales.gov.uk | ||
| URL | http://naturalresources.wales/?lang=en | |
| Role | The custodian is the person or organisation that accepts responsibility for the resource and ensures appropriate care and maintenance. If a dataset has been lodged with a Data Archive Centre for maintenance then this organisation is be entered here. | custodian |
| Organisation name | Natural Resources Wales (NRW) | |
| Delivery point | Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales | |
| enquiries@naturalresourceswales.gov.uk | ||
| URL | http://naturalresources.wales/?lang=en | |
| Role | The originator is the person or organisation who created, collected or produced the resource. | originator |
| Organisation name | Countryside Council for Wales (CCW) | |
| Delivery point | Countryside Council for Wales, Maes y Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW | |
| enquiries@naturalresourceswales.gov.uk | ||
| URL | http://naturalresourceswales.gov.uk/splash?orig=/ | |
| Role | The originator is the person or organisation who created, collected or produced the resource. | originator |
| Organisation name | SeaZone | |
| Delivery point | Howberry Park, Wallingford, Oxfordshire, OX10 8BA | |
| info@SeaZone.com | ||
| URL | http://www.seazone.com/index.php | |
| Role | The originator is the person or organisation who created, collected or produced the resource. | originator |
| Organisation name | Natural England | |
| Delivery point | Foundry House, 3 Millsands, Riverside Exchange, Sheffield, S3 8NH | |
| enquiries@naturalengland.org.uk | ||
| URL | http://www.naturalengland.org.uk/ | |
| Role | The distributor is the person or organisation that distributes the resource. | distributor |
| Organisation name | Natural Resources Wales (NRW) | |
| Delivery point | Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales | |
| enquiries@naturalresourceswales.gov.uk | ||
| URL | http://naturalresources.wales/?lang=en | |
| Dataset constraints | ||
| 20.1 Limitations on Public Access - Access constraints | This states `otherRestrictions` from ISO vocabulary RestrictionCode and is an INSPIRE/GEMINI requirement. | otherRestrictions |
| 20.2 Limitations on Public Access - Other constraints | This states any limitations on access to the data. Multiple occurences are allowed here. One entry shall be from the INSPIRE Metadata registry and the other free text should be part of the resource `Have specific limitations`. | There are no access restrictions to this data. NRW may release, publish or disseminate it freely. |
| no limitations | ||
| 21.1 Conditions for Access and Use - Use constraints | This states `otherRestrictions` from ISO vocabulary RestrictionCode and is an INSPIRE/GEMINI requirement. | otherRestrictions |
| 21.2 Conditions for Access and Use - Other constraints | This states any constraints on use of the data. Multiple conditions can be recorded for different parts of the data resource. If no conditions apply, then `No condtions apply` is recorded. This uses free text. | © CNC/NRW 2011 There are no use restrictions on this data. Recipients may re-use, reproduce, disseminate this data free of charge in any format or medium, provided they do so accurately, acknowledging both the source and NRW's copyright, and do not use it in a misleading context. It is the recipient's responsibility to ensure the data is fit for the intended purpose, that dissemination or publishing does not result in duplication, and that it is fairly interpreted. Advice on interpretation should be sought where required. To avoid re-using old data, users should periodically obtain the latest version from the original source. |
| Available data formats | ||
| Data format | Format in which digital data can be provided for transfer | Documents |
| Format in which digital data can be provided for transfer | Geographic Information System | |
| Version info | ||
| Date of publication | The publication date of the resource or if previously unpublished the date that the resource was made publicly available via the MEDIN network. | 2011-01-28 |
| Harvest date | The date which this record has been (re)harvested from the provider. | 2026-04-19 |
| Metadata date | The date when the content of this metadata record was last updated. | 2026-03-03 |
| Metadata standard name | The name of the metadata standard used to create this metadata | MEDIN |
| Metadata standard version | The version of the MEDIN Discovery Metadata Standard used to create the metadata record | 3.1.2 |