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South of Celtic Deep MPA

Formal Conservation Advice for South of Celtic Deep MCZ was published in January 2021 and is available in the Conservation Advice section below.

Status: Marine Conservation Zone (MCZ)

South of Celtic Deep MCZ is located in the Western Channel and Celtic Sea region off the north coast of Cornwall. The seabed is characterised by Subtidal coarse sediment and Subtidal sand, with small areas of Subtidal mixed sediments and Moderate energy circalittoral rock.


South of Celtic Deep MCZ is located 90 km to the north-west of the Land’s End peninsula in the Western Channel and Celtic Sea region. It covers an area of 278 km2 and varies in depth from 50 to 100 m, with two small areas below 100 m. The seabed is characterised by Subtidal coarse sediment and Subtidal sand, with small areas of Subtidal mixed sediments and Moderate energy circalittoral rock. The seabed is highly heterogenous and this variety of habitats allows a range of species to thrive, such as starfish and haddock.

More detailed site information can be found in the Summary section below.

Map displaying the South of Celtic Deep MPA boundary and associated protected feature data. Visit JNCC's MPA Mapper to further view and explore data for this MPA.

Map showing South of Celtic Deep Marine Protected Area and linking to the MPA mapper


Legislation behind the designation: Marine and Coastal Access Act (2009)


Protected Features

EUNIS Code: Protected Feature Feature Type
A4.2: Moderate energy circalittoral rock Broad-scale habitat
A5.1: Subtidal coarse sediment Broad-scale habitat
A5.4: Subtidal mixed sediments Broad-scale habitat
A5.2: Subtidal sand Broad-scale habitat

Specific information on the conservation objectives related to this site is provided in the Conservation Advice section.

The acquisition of new data may result in updates to our knowledge on feature presence and extent within this site. The most up-to-date information is reflected on the map on this page and in JNCC’s MPA mapper and the evidence underpinning this can be viewed in the Evidence section.


Site Timeline

The diagram below is a summary of the key milestones involved in the selection and designation of the South of Celtic Deep MCZ. More detail can be found within the Relevant Documentation section and in the post-consultation advice

September 2011
Regional Projects recommended a total of 127 rMCZs to Defra and the SNCBs. South of Celtic Deep rMCZ was proposed by the Finding Sanctuary regional project.
June 2018 – July 2018
South of Celtic Deep MCZ included in formal public consultation on Tranche Three MCZs.
May 2019
Tranche Three designations announced – South of Celtic Deep MCZ designated.


Relevant Documentation

The documents referred to below and any other historical documents relating to South of Celtic Deep MCZ were produced during the selection and designation process and therefore may be out of date. This Site Information Centre is the most up-to-date source of information for this MPA, and will reflect any additional information gathered since these documents were produced. Further information about the Marine Conservation Zone site selection process and historic MCZ advice is available on JNCC's MCZ webpage.

  • South of Celtic Deep MCZ Designation Order – the official description of the site designation under the Marine and Coastal Access Act 2009. The Designation Order includes boundary co-ordinates, Conservation Objectives and a list of the designated features. More information on the Designation Order, including a designation map and factsheet is available on Defra's website.
  • JNCC's pre- and post-consultation scientific advice for features proposed for designation in 2019.
  • JNCC's formal conservation advice for this site is available in the Conservation Advice section.



Last updated: July 2020

Information for this site summary was adapted from JNCC’s scientific advice to Defra on South of Celtic Deep MCZ and incorporates any further information gathered since this advice was produced. Please refer to the Relevant Documentation section for further details and information sources.


Site overview

South of Celtic Deep MCZ covers an area of 278 km2, protecting a range of habitats including Moderate energy circalittoral rock, Subtidal coarse sediments, Subtidal sand and small areas of Subtidal mixed sediments. The site varies in depth between 50 and 100 m, with two small areas dipping below 100 m. The seabed is highly heterogenous and this variety of habitats allows a number of species to thrive, including bivalve molluscs (for example, scallops and clams), worms, anemones, starfish and a range of fish (for example, John dory (Zeus faber), haddock (Melanogrammus aeglefinus) and angler fish (Lophius piscatorius). Basking sharks (Cetorhinus maximus) have also been sighted within the MCZ.

The site was recommended by the Finding Sanctuary regional MCZ project for broad-scale habitats in 2011. A survey was conducted at the site under the MB0120 project in February 2012, which found evidence for Subtidal coarse sediment, Subtidal mixed sediments, Subtidal sand and Moderate energy circalittoral rock (see the survey report). A Gardline geosurvey in 2013 collected backscatter and multibeam data, which was used alongside the ground-truthing data collected in 2012 to create a full habitat map for the designated seabed features.

Further detail on the evidence for this MCZ can be found in the Evidence section.

Site location: Co-ordinates for this MCZ can be found in the Designation Order listed in the Relevant Documentation section.

Site area: 278 km2 (roughly ten times the size of Penzance).

Site depth range: 50–100 m, with two small areas dipping below 100 m.

Charting Progress 2 Biogeographic Region: Western Channel & Celtic Sea.

Site boundary description: The site’s northern boundary is delineated by the UKHO Welsh waters limit, in line with the guidance provided by the MCZ project Ecological Network Guidance (ENG). The original boundary that was proposed for South of Celtic Deep MCZ has been altered slightly since it was recommended by the Finding Sanctuary Regional MCZ Project in 2011.



Last updated: December 2020

Site-specific data

There are a range of data that underpin this MCZ. The full overview of these data used to support site identification along with information on confidence in feature presence and extent is available in JNCC’s Tranche Three MCZ pre-consultation and post-consultation scientific advice for offshore Marine Conservation Zones proposed for designation in 2019. JNCC will be adding relevant survey data for this MPA to its MPA mapper in due course.

Some of the data for this MCZ have been collected through JNCC-funded or collaborative surveys and some through other means. Data from these surveys provide direct evidence confirming the presence of the protected features within the site.


Survey and data gathering

  • Gardline Geosurvey of South of Celtic Deep (2013) – Multibeam bathymetry and backscatter data were collected between 27 February and 20 March 2013 by Gardline Geosurvey using the MV Vigilant and the MV Lespoir.
  • Cefas/JNCC site verification survey of South of Celtic Deep MCZ (2012) – Multibeam acoustic data and ground-truthing were collected during the RV Cefas Endeavour cruise CEND0312.


Data analysis reports

  • South of Celtic Deep rMCZ Post-survey Site Report (2016) – Cefas undertook analysis of acoustic and ground-truthing data collected by dedicated surveys in 2012 and 2013 within the site. These data were used to produce an updated habitat map and to inform the presence of broadscale habitats and habitat FOCI, and allow estimates to be made of their spatial extent within the site.


Knowledge gaps

If you are aware of any additional data not listed here or scientific papers relevant to this site, please contact us.


Conservation Advice

Last updated: January 2021

Updated formal conservation advice for this MPA was produced in January 2021.  Further information on the approach used to develop this advice is available on our 'Conserving MPAs' webpage, along with a Glossary of Terms used in JNCC's conservation advice and a short video explaining how to use the conservation advice packages. 

You must refer to this advice if you:

  • undertake an MCZ assessment for a plan or project that could impact the site;
  • provide information for such an assessment;
  • respond to specific measures to further the conservation objectives for the site; and 
  • consider the need to put new or additional management measures in place.

You may also find it useful to refer to this advice if you:

  • carry out any other activity that could impact the site.

We will engage with stakeholders to identify any lessons which JNCC can learn from customers who have used the advice, with a view to continuing to ensure it is fit-for-purpose.

The following table provides an overview of the components of the conservation advice, and provides hyperlinks to each of the products for this MPA.  These elements together form JNCC’s formal conservation advice for this site and should be read in conjunction with each other.  This advice reflects the most up-to-date evidence held by JNCC (correct as of January 2021).  

Document Overview
Background Information

Explains the purpose of the advice and when it must be referred to.

Conservation Objectives

Supplementary Advice on the Conservation Objectives (SACO)

The Conservation Objectives set out the broad ecological aims for the site. JNCC provides supplementary advice in the SACO which is essential reading to support interpretation of these conservation objectives.

You can use these documents to assess the impacts of your planned activity on the important attributes of the site.

Conservation Advice Statements

These statements provide a summary of the Supplementary Advice on the Conservation Objectives (SACO).

  • Site condition presents our up-to-date understanding of the condition of features within the site;
  • Conservation benefits which the site can provide, these help you understand what is important about the site and why it needs protecting; and
  • Conservation measures which JNCC considers are needed to support achievement of the conservation objectives. These provide clarity around measures needed to support restoration or maintenance of the feature(s) within the site.
Advice on Operations

Provides information on the activities capable of affecting site integrity and therefore achievement of the site’s conservation objectives.

This is a starting point for determining potential management requirements. It does not take into account the intensity, frequency or cumulative impacts from activities taking place. It is simply to advise you of the possible adverse impacts that your activity can have on a MPA’s features.

Use the advice on operations to determine those pressures your activity causes that could harm the habitat and/or species features of the site.

These documents are available on JNCC's Resource Hub.  


Activities and Management

Last updated: July 2020

Management status: To be assessed.

Information on the management for the site can be found in the South of Celtic Deep MCZ Factsheet.

This site forms part of the UK's contribution to the OSPAR Commission's network of MPAs. As the UK is a contracting party to the OSPAR Commission, JNCC is committed to ensuring that the OSPAR MPA network is well-managed.

JNCC considers well-managed to mean the timely progress of an MPA around the 'MPA management cycle'. This involves:

  1. The documentation of appropriate management information – conservation objectives, advice on activities capable of affecting the protected features of a site, and spatial information on the presence and extent of the protected features of a site.
  2. The implementation of management measures – management actions considered necessary to achieve the conservation objectives of a site.
  3. Site condition monitoring programmes – collecting the information necessary to determine progress towards a site's conservation objectives.
  4. Assessment of progress towards conservation objectives – using available information to infer whether or not a site is moving towards or has achieved its conservation objectives.



Last updated: July 2020

For MPAs, data and evidence collected from monitoring activities will aim to:

  • Enable assessment of condition of the features within sites;
  • Enable assessment of the degree to which management measures are effective in achieving the conservation objectives for the protected features;
  • Support the identification of priorities for future protection and/or management; and
  • Enable Government to fulfil its national and international assessment and reporting commitments in relation to MPAs and help identify where further action may be required.

Information on monitoring of this MPA will be provided when it becomes available.



Last updated: July 2020

Assessments of the condition of designated features in offshore MPAs are required to report against our legal obligations. Ideally these assessments should be based on observed data, and then measured against targets for pre-defined indicators. However, for MPAs in offshore waters we do not always have the appropriate information to be able to do so. This is particularly true for seabed habitats, which are the main type of feature designated for protection in offshore MPAs.

To address these challenges, JNCC has been an active partner in the development of new approaches and tools for the assessment of habitats and species for a variety of national and international status reports.


Conservation Assessment Reports

Under Section 124 of the UK Marine & Coastal Access Act (2009), JNCC is required to report to Ministers every six years on the degree to which the conservation objectives of the protected features of Marine Conservation Zones (MCZs) have been achieved. Every six years from 2012, the Marine Act requires a report setting out how MCZs have performed against their conservation objectives, as well as the effectiveness of the network as a whole.

To date, three reports have been published, each setting out progress being made in implementing a Marine Protected Area network, covering the following areas:

Outputs of assessments that feed into Marine Act reporting also feed into reporting under other obligations.


UK State of the Seas Reports & UK Marine Strategy Part 1

Charting Progress 2 (CP2) published in 2010, is a comprehensive report on the state of the UK seas. It was published by the UK Marine Monitoring and Assessment Strategy (UKMMAS) community which has over 40 member organisations. The report was based on a robust, peer-reviewed evidence base and describes progress made since the publication of Charting Progress in 2005. It provides key findings from UK marine research and monitoring for use by policy makers and others, as we move towards the UK vision of clean, healthy, safe, productive and biologically diverse oceans and seas. The results from CP2 were incorporated into the UK Marine Strategy Part 1: UK Initial Assessment and Good Environmental Status published in 2012 under the UK Marine Strategy Regulations (2010). The UK Marine Strategy Part 1 (2012) also set out the UK’s definition for Good Environmental Status, which could be achieved by meeting a series of environmental targets. JNCC worked with other organisations in the UKMMAS community to develop a series of indicators that were used to assess progress against each of the targets and to report on progress made since 2012. The results of these assessments have been published in the UK Marine Strategy Part 1: UK Updated Assessment and Good Environmental Status in 2019. Detailed evidence used to make these assessments is available via the Marine Online Assessment Tool (MOAT). It also sets out proposals for updated high-level objectives, targets and operational targets to be used for 2018 to 2024, which build on those set in 2012.

It is worth noting the two other parts of the UK Marine Strategy: UK Marine Strategy Part Two: marine monitoring programmes, published in 2014 and UK Marine Strategy Part Three: programme of measures published in 2015. Updates to these will be made in 2020 and 2021 respectively.


OSPAR Quality Status Reports

Many of the assessments in the updated UK Marine Strategy Part 1 2019 were developed and produced in collaboration with other contracting Parties of the OSPAR Convention for the Protection of the North East Atlantic. In 2017 OSPAR published its Intermediate Assessment (IA2017). The IA 2017 further develops OSPAR’s understanding of the marine environment of the North-East Atlantic and its current status. It demonstrates OSPAR’s progress towards realising its vision of a clean, healthy and biologically diverse North-East Atlantic, used sustainably. IA2017 follows on from OSPAR’s previous holistic assessment, the OSPAR Quality Status Report in 2010 (QSR2010) and in 2000 (QSR2000).


Development and tools

JNCC continues to develop and pilot tools for the assessment of marine habitats and species in offshore waters to improve the quality and transparency of our offshore MPA assessments, and contribute to the monitoring of marine biodiversity in UK waters. These tools cover methods for producing interim assessments of site features and their responses to pressures, as well as developing more robust indicators for determining condition of the features.


© Cefas/JNCC 2012


Published: .

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