A study of the Milford Haven maerl bed (2005)

Maerl beds are a UK Biodiversity Action Plan (BAP) habitat and are also included in the biodiversity duty of public bodies introduced by the NERC Act 2006. Maerl is a collective term for several species of red seaweed, with hard, chalky skeletons. It is rock hard and, unlike other seaweeds, it grows as unattached rounded nodules or short, branched shapes on the seabed. Maerl beds are an important habitat for many different types of marine life, which live amongst or are attached to the surface of Maerl, or burrow in the coarse gravel of dead maerl beneath the top living layer. Maerl beds can be of importance to sustainable fisheries, providing nursery grounds for commercial species of fish and shellfish. In Milford Haven the maerl species Phymatolithon calcareum forms the only living maerl bed in Wales. P. calcareum is listed in the EC Habitats Directive Annex Vb. The aim of this project was to collate high quality images of the Milford Haven maerl bed to create a base line for long term monitoring for Biodiversity Action Plan reporting. There is high confidence in this dataset as the surveyors are amongst the most experienced marine biologists in the UK.

Identifier: NRW_DS101780

Alternative Title

2005 CCW study of the Milford Haven Maerl Bed MRCCW16500000002
Astudiaeth ar wely marl Aberdaugleddau yn 2005

Metadata Language: English

Lineage: The first phase of the fieldwork was to map the extent of the maerl bed in Milford Haven and to determine the distribution and abundance of live maerl using drop down video. The second phase of the fieldwork was detailed study at six sites by divers who recorded the frequency of occurrence of macrobiota in a series of quadrats. At four of the sites, core samples were collected for infaunal and sediment particle size analysis. The present study follows on from work completed in May 2004 (RPS, 2004). RPS carried out an exploratory survey of the maerl bed in Milford Haven waterway in the vicinity of Herbrandston jetty on behalf of South Hook Liquid Natural Gas Terminal Company Ltd (South Hook LNG). This was the most comprehensive work on this maerl bed to date but the survey was partial and significant data gaps remained. The present study was designed to use a similar methodology to that used by RPS and to build on the existing data collected to give a better picture of the extent and quality of the maerl within the Milford Haven waterway.

Dataset Reference Date (Publication): 2007-02-28

Temporal Extent

Begin date: 2005-01-01

End date: 2005-12-31

Topic category

Biota

Owner

Natural Resources Wales (NRW)

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

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

Originator

Bunker

MarineSeen, Estuary Cottage, Bentlass, Hundleton, Pembrokeshire, SA71 5RN

http://www.marineseen.com/

Originator

South Hook LNG Terminal Company Ltd

Dale Road, Herbrandston, Milford Haven, Pembrokeshire, SA73 3SU

http://www.southhooklng.co.uk

Extent

Geographic Extent: Irish Sea

Geographic Extent: St. Brides Bay

Geographic Extent: SIR BENFRO - PEMBROKESHIRE

Geographic Extent: Wales (WLS)

Map representing the geographic extent of the dataset

Vertical Extent

Medin Extent Keyword: benthic boundary layer

Format Type and Description

Database Database ()

Specification

[A] Data is held as video footage [B] Excel spreadsheets [C] Marine Recorder (MRCCW16500000002) [D] Spatial TAB files [E] JPEG images [F] The final report is held in both a Word document and as a .pdf

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
Degree: false

Lineage: The first phase of the fieldwork was to map the extent of the maerl bed in Milford Haven and to determine the distribution and abundance of live maerl using drop down video. The second phase of the fieldwork was detailed study at six sites by divers who recorded the frequency of occurrence of macrobiota in a series of quadrats. At four of the sites, core samples were collected for infaunal and sediment particle size analysis. The present study follows on from work completed in May 2004 (RPS, 2004). RPS carried out an exploratory survey of the maerl bed in Milford Haven waterway in the vicinity of Herbrandston jetty on behalf of South Hook Liquid Natural Gas Terminal Company Ltd (South Hook LNG). This was the most comprehensive work on this maerl bed to date but the survey was partial and significant data gaps remained. The present study was designed to use a similar methodology to that used by RPS and to build on the existing data collected to give a better picture of the extent and quality of the maerl within the Milford Haven waterway.

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

maerl beds
Video survey
divers
underwater conservation
underwater photography

Type: Theme

Citation

Date (Publication): 2023-12-31

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

Keywords

SeaDataNet Parameter Discovery Vocabulary

Zoobenthos taxonomic abundance

Type: Theme

Citation

Date (Revision): 2021-01-06

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

Keywords

Integrated Public Sector Vocabulary

diving

Type: Theme

Citation

Date (Revision): 2013-04-03

Code: geonetwork.thesaurus.external.theme.subjects

Code: Latitude and Longitude (EPSG::4326)

Content Information

NRW Profile

Custom Elements

NRW Related Title: A study of the Milford Haven maerl bed in 2005 using drop down video and diving

Constraints

Limitations on Public Access and Use

Restriction type: Other restrictions

Access Constraints Directive

Limitations: no limitations

Access Constraints Text

Other constraints: The following data is considered OS derived data and is therefore jointly owned by NRW and the Ordnance Survey. There are no access restrictions on this data. However there are third party use restrictions.

Use Constraints

Use constraints type: Other restrictions

Other constraints: © CNC/NRW and © Crown copyright. All rights reserved. Natural Resources Wales, AC0000849444 Data may be re-used under provision and in line with the terms of a NRW licence. Those seeking commercial re-use require a commercial licence available from the OS.

Metadata

File Identifier: 4f4c4942-4343-5764-6473-313031373830 XML

Metadata Language: English

Parent Identifier: Natural Resources Wales (NRW) Marine Benthic Species and Habitat Collation Held in Marine Recorder
NRW_DS114501

Resource type: Dataset

Metadata Date: 2024-05-31T09:22:43.352Z

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.

A study of the Milford Haven maerl bed (2005)

Identification

Temporal Extent

Extent

Extent

Vertical Extent

Distribution

Quality

Data quality

Keywords

Keywords

Citation

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

Metadata

Metadata

Publishing Body