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Darwin Mounds MPA

Formal updated conservation advice was produced for the Darwin Mounds SAC in March 2018 and is available in the Conservation Advice section below.

Status: Special Area of Conservation (SAC)

The Darwin Mounds SAC lies at the north end of the Rockall Trough located approximately 160 km north-west of Cape Wrath, Scotland, with depths between 710 m and 1,129 m.




The Darwin Mounds SAC is located approximately 160 km north-west of Cape Wrath, Scotland, at the north end of the Rockall Trough.  The site contains an extensive area of sandy mounds, each capped with multiple thickets of cold-water corals. Unlike most cold-water corals which attach to hard-surfaces, at this site the corals grow on sand. The thickets of coral range in size from one to several metres in diameter and support many other species, such as starfish, sponges and large populations of xenophyophores. Xenophyophores are the world’s largest single-celled organisms and are only found in deep-sea environments. They provide shelter for a range of small sea creatures, many of which are prey for larger species, and act as an elevated perch for filter feeders such as brittlestars.

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

Map displaying the Darwin Mounds MPA boundary and associated protected feature data. Visit JNCC's MPA Mapper to further view and explore data for this MPA.



Legislation behind the designation: EU Habitats Directive 1992 transposed into UK law by The Conservation of Offshore Marine Habitats and Species Regulations 2017.


Protected features

Features Feature Type
1170 Reefs Annex I Habitat*

*For the latest Annex I habitat resource figures, please see the link to the latest Habitats Directive Article 17 reporting in the Assessment section.

Specific information on the conservation objectives relating 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 summarises the key milestones involved in the selection and designation of Darwin Mounds SAC. More detail can be found within the Relevant Documentation section.



Relevant Documentation

The documents referred to below and any other historical documents relating to Darwin Mounds SAC 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 Darwin Mounds SAC, and will reflect any additional information gathered since these documents were produced. Information about the SAC site selection process is available on JNCC's SAC webpages.

These resources are available on JNCC's Resource Hub



Last updated: October 2017

Information for this site summary was adapted from the SAC Selection Assessment Document and incorporates any further information gathered since this document was produced. Please refer to this document for further details and information sources.


Site overview

The Darwin Mounds is located approximately 160 km north-west of Cape Wrath, Scotland, at the north end of the Rockall Trough. The site consists of a large number of coral-topped 'sand volcanoes' composed of sand overlying mud. The individual mounds are up to 75 m wide and 5 m high and are morphologically unique in UK waters. The mounds themselves are unusual geological features that are thought to have been formed by fluid expulsion from the seabed. The mounds are most elevated to the north of the site and diminish in height to the south. There are two denser regions of mounds in the north-east and north-west of the site. The north-east field of the Darwin Mounds measures approximately 13 km by 9 km and contains approximately 150 mounds, whereas the north-west field measures approximately 13 km by 4 km and contains approximately 75 mounds.

The mounds in the northern part of the site showed an acoustic signature of a "tail" which generally lies to the south-west of the mound feature consisting of elongate to oval patches up to 500 m long. The 'tail' feature of the mounds is thought to be unique globally. The tails are not topographically distinct from the surrounding seabed but are covered with a fine veneer of sand. They support substantial numbers of the xenophyophore Syringammina fragilissima (a single-celled organism that can grow up to 20 cm in diameter), in densities greater than the surrounding seabed.

On the majority of the mounds there are also multiple colonies of Lophelia pertusa growing, which in many cases have formed thickets which arise from the surface of the mound. This site was the first observed record of cold-water coral reefs growing on sand at the time of discovery. Like the topography of the mounds, the frequency of coral communities diminishes towards the south of the mound field. Although the reef habitat on top of the mounds is formed primarily from Lophelia pertusaanother cold-water coral – Madrepora oculata – is also present. The thickets of cold-water corals provide a habitat for echiuran worms, brittlestars, brisingiid starfish and sponges. Various fish have been observed among the mounds, but not at higher densities than the wider environment.

Within the Atlantic north-west approaches, Rockall Trough and Faroe-Shetland Channel Regional Sea, where Darwin Mounds SAC is situated, there are three other SACs designated for the presence of Annex I reef: Anton Dohrn Seamount SAC, North West Rockall Bank SAC and East Rockall Bank SAC. Each site represents different types of Annex I reef. Wyville Thomson Ridge SAC on the edge of the adjacent Scottish continental shelf regional sea is also designated for Annex I reef. The tail feature observed on mounds in the northern part of the Darwin Mounds site is thought to be globally unique from a geological perspective. Further detail on the evidence for this SAC can be found in the Evidence section.

Site location: Co-ordinates for this SAC can be found in the standard data form listed in the Relevant documentation section.

Site area:  1,377 km2, a similar size to the Brecon Beacons National Park (1,344 km2)

Site depth range:  710–1,129 m.

Charting Progress 2 Biogeographic Region: Atlantic North-West approaches, Rockall Trough and Faroe-Shetland Channel. A small part of the site extends into the Scottish continental shelf biogeographic region.


Site boundary description

The boundary of the Darwin Mounds SAC is a simple polygon, fully enclosing the minimum area necessary to ensure protection of the Annex I feature. The boundary has been aligned with the area permanently closed to bottom trawling through the European Commission common fisheries policy (EC Regulation 602/2004).

As bottom trawling is a significant threat to the interest feature the proposed boundary includes a margin to ensure its protection. The maximum depth of water around the feature is 1,000–1,100 m. Fishing vessels which are bottom trawling in the region need a minimum towline length of twice the depth of water in which they are fishing. Assuming a ratio of 2:1 fishing warp length to depth, the proposed boundary is defined to include a margin of 2,200 m from the cold-water coral reefs.



Last updated: October 2017

For a full overview of the data used to support site identification along with information on confidence in feature presence and extent see the Darwin Mounds SAC Selection Assessment Document. Additional survey data will be added to JNCC's MPA mapper in due course.

Data for this SAC have been primarily collected through JNCC-funded or collaborative surveys, with other data obtained through other data sourcing. The data gathered provide direct evidence confirming the presence of the protected features within the site.


Survey and data gathering

  • Deep Links Project (2016) – A collaborative project between Plymouth University's Deep Sea CRU and University of Oxford, in partnership with JNCC and British Geological Survey, funded by NERC. During May and June 2016 the team undertook a 6 week research cruise in the North East Atlantic, including Anton Dohrn Seamount, on board the RRS James Cook collecting data. This project aims to investigate the theory that populations at bathyal depths are more isolated because the currents that transport larvae decrease with depth.
  • Survey of Darwin Mounds and North West Rockall (2011) – JNCC collaborated with the National Oceanography Centre and Plymouth University to carry out habitat mapping to assess the status of different benthic habitats in relation to human activities, especially deep-sea bottom trawling. Acoustic and underwater imagery data were collected.
  • RRS Charles Darwin Cruise 123C3-4 (2000) – The cruise formed part of the continuing AMES undertaken by the National Oceanography Centre in waters to the north and west of Scotland. Seabed samples and underwater imagery were collected to study environmental parameters and benthic communities.
  • RRS Charles Darwin cruise 119C leg B (1999) – The cruise was undertaken by the National Oceanography Centre and expanded on the work undertaken on the AFEN Atlantic Margin Environmental Survey (AMES). The cruise collected acoustic maps of the seafloor, along with photographic and video observations. Where possible, seabed samples were also collected to analyse selected environmental parameters.
  • Atlantic Frontier Environmental Network Survey (1998) – The Atlantic Frontier Environment Network (AFEN; including JNCC) commissioned a survey to map and sample the seabed to the north and west of Scotland, allocated for oil and gas exploration in 1997. The aim of the survey was to provide the shape and texture of the seabed, the fauna and the physical processes affecting them, both of today and over the last 10–15,000 years. The Darwin Mounds were discovered on this cruise.


Data analysis reports

Further analysis of data gathered as part of the surveys listed above are available via the following reports:


Additional relevant literature

References for further supporting scientific literature consulted during the identification of this site can be found in the SAC Selection Assessment Document. Please be aware that although these sources contain information which is of interest in relation to this MPA, they do not necessarily represent the views of JNCC.

  • Huvenne V.A.I., Bett B.J., Masson D.G., Le Bas T.P. and Wheeler A.J. (2016) Effectiveness of a deep-sea cold-water coral Marine Protected Area, following eight years of fisheries closure. Biological Conservation, 200; 60–69.
  • Masson, D.G., Bett, B.J., Billett, D.S.M., Jacobs, C.L., Wheeler, A.J. and Wynn, R.B. (2003) The origin of deep-water, coral-topped mounds in the northern Rockall Trough, Northeast Atlantic. Marine Geology, 194: 159–180.
  • Bett, B.J. (2001) UK Atlantic Margin Environmental Survey: Introduction and overview of bathyal benthic ecology. Continental Shelf Research, 21: 917–956.
  • Bett, B.J., Billett, D.S.M., Masson, D.G., Tyler, P.A. et al. (2001) RRS Discovery Cruise 248: 07 Jul – 10 Aug 2000. A multidisciplinary study of the environment and ecology of deep-water coral ecosystems and associated seabed facies and features (The Darwin Mounds, Porcupine Bank and Porcupine Seabight). National Oceanography Centre Cruise Report 36: 108. – This cruise formed part of the work done by the National Oceanography Centre for the EU funded Atlantic Coral Ecosystem Study and ECOMOUND projects. These projects investigated the geological processes underlying the formation of the Darwin Mounds, and studied the biology and ecology of cold water coral reefs.


Knowledge gaps

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


Conservation Advice

Last updated: March 2018

Updated formal conservation advice for this MPA was produced in March 2018.  Further information on the approach used to develop this advice is available on our Conservation Advice webpages along with a Glossary of Terms used in JNCC conservation advice and a short video explaining how to use the conservation advice packages. 

You must refer to this advice if you:

  • undertake a Habitats Regulation Assessment (HRA) for a plan or project that could impact the site;
  • provide information for a HRA;
  • respond to specific measures to support delivery of 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 March 2018). 

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.

Please note our current understanding of whether the available evidence indicates that each attribute needs to be restored or maintained is not provided here. However, links to available evidence for the site are provided and should you require further site-specific information for the site, please contact us.

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 resources are available on JNCC's Resource Hub



Activities and Management

Last updated: October 2017

Management status: Progressing towards being well managed

Information about the long-term recovery of cold-water coral populations is scarce but fisheries management measures are in place. Continued protection of the Darwin Mounds area combined with regular monitoring is necessary to obtain further insights in these processes (Howell et al. 2014).

This site forms part of the UK's contribution to the OSPAR Commission's network of MPAs, Europe’s Natura 2000 network and the Emerald Network established under the Bern Convention. As the UK is a contracting party to the OSPAR Commission, JNCC is committed to ensuring that the OSPAR MPA network is 'well-managed' by 2020.

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.

The sub-sections that follow provide an account of the progress of Darwin Mounds SAC around each of the four stages in the MPA management cycle.


1. The documentation of appropriate management information

  • The conservation objectives and advice on activities capable of affecting the conservation status of the protected feature of this site are available under the Conservation Advice section.  Further information is available on our Conservation Advice webpages.
  • Spatial information on the presence and extent of the protected feature of this MPA is available via JNCC's MPA mapper.
  • JNCC is in the process of developing downloadable MPA data packages where appropriate permissions to share datasets are in place.


2. The implementation of management measures

This section details progress towards the implementation of management measures for activities considered capable of affecting the conservation status of the protected feature of the site. The protected feature of the site is considered to be sensitive to pressures associated with fishing and 'licensable' activities.


  • Prior to 2016 there is evidence of mobile demersal, static and pelagic effort within the MPA, and UK and non-UK registered vessels have been active in the area. 
  • Marine Scotland is the lead authority regarding the implementation of, and compliance with, any measures to managing fishing activity. Further information on progress is available via Marine Scotland's webpages.
  • In compliance with Article 8 of the deep-sea Regulation (EU) 2016/2336, a ban on the use of all bottom-contacting mobile gear has been introduced below 800 m depth across all European waters. This applies across the area of Darwin Mounds MPA where the depth falls below 800 m. Article 9 of this same regulation also sets out rules for fishing between 400 m and 800 m where Vulnerable Marine Ecosystems (VMEs) are present, or are likely to occur. These rules aim to minimise the impact of fishing activities on VMEs.
  • Fishing with bottom-set gillnets, entangling nets and trammel nets below 600 m is also prohibited for the protection of deepwater shark species under Council Regulation (EC) 2019/1241, and there are additional restrictions on their use between 200 m and 600 m. This regulation also applies to those areas beyond Union waters, but within the North-East Atlantic Fisheries Commission (NEAFC) technical measures regulatory area.

Licensable activities

  • Whilst 'licensable' activities such as oil and gas exploration and production do not take place within Darwin Mounds SAC at present, any future proposals would have to comply with Article 6 (3) of the EU Habitats Directive 1992, which is transposed into UK law by The Conservation of Offshore Marine Habitats and Species Regulations 2017.
  • Our conservation advice supports the consents process by setting out the conservation objectives for the protected feature of this MPA and advice on activities that may result in pressures to which the protected feature is considered sensitive.
  • Further information on JNCC's role in the provision of advice for licensed activities in the UK offshore area is available on JNCC's Offshore industry advice webpages


3. Site condition monitoring

Fishing vessel monitoring data is used to monitor compliance with the management measure in place. A baseline condition monitoring survey was undertaken in 2011 (reported in Howell et al. 2014). Further information is provided in the Monitoring section.


4. Assessment of progress towards conservation objectives

No long-term condition monitoring data are available to determine whether the MPA is moving towards or has reached its conservation objectives. Howell et al. (2014) suggest that ecosystem recovery is still a long way off, as no signs of coral recolonisation and limited coral regrowth were recorded in damaged areas after eight years of closure to bottom-contacting fishing gear (since 2004). Further information is provided in the Assessment section.



Last updated: October 2017

JNCC is currently leading on the development of a strategy for biodiversity monitoring across all UK waters, to include SAC monitoring. For SACs, 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 the 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 SAC will be provided when it becomes available.



Last updated: October 2017

Assessments of the condition of designated features in offshore MPAs are required to report against our legal obligations. Ideally these assessments are based on observed data, and then measured against targets for predefined indicators. However, for MPAs in offshore waters the appropriate information is not always available particularly for seabed habitats, which are the main type of designated features within offshore MPAs. 

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


Conservation Assessment Reports

Every six years, Member States of the European Union are required (by Article 17 of the Directive) to report on implementation of the Habitats Directive. The latest report on the Conservation Status of Annex I habitats and Annex II species on the Habitats Directive was submitted by the UK in 2019 and provided an assessment of the conservation status of relevant habitats and species within UK marine waters during period 2013–2018; information on the condition of features within SACs have made a contribution to this report.


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).


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.



Published: .

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