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Challenges of habitat mapping to inform marine protected area (MPA) designation and monitoring: An operational perspective
Marine Policy xxx (xxxx) xxx
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Marine Policy journal homepage: http://www.elsevier.com/locate/marpol
Challenges of habitat mapping to inform marine protected area (MPA) designation and monitoring: An operational perspective Suzanne Ware *, Anna-Leena Downie Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft Laboratory, Pakefield Road, Lowestoft, Suffolk, England, NR33 0HT, UK
A R T I C L E I N F O
A B S T R A C T
Keywords: Ecosystem Habitats Indicators Mapping Monitoring Biodiversity
The UK has adopted a feature-based approach to MPA designation and monitoring to meet international and national obligations. Despite operational challenges, this approach is considered key to optimising conservation outcomes whilst making efficient use of limited resources. Drawing on lessons learnt from the UK’s MPA Pro gramme we discuss the practical issues which arise from: i) effective selection of conservation features identified as surrogates for biodiversity, ii) adequacy of feature representation across the MPA network and iii) imple mentation of quantifiable conservation objectives and ability to monitor progress in relation to them [4,5]. There is recognition that high-level feature surrogates adopted for MPA designation may not adequately represent the full range of biodiversity present across UK marine habitats, and several of these features are indiscernible using acoustic mapping techniques. This results in our inability to accurately map their distribution and extent. Additionally, monitoring progress in relation to conservation targets is hampered by a lack of reliable indicators to assess change in their ecological status. Recommendations for the optimisation of MPA designation and monitoring using a systematic, evidence based approach are provided. These include: 1) flexibility in feature classifications to allow additional features to be designated as required, 2) communication of limitations in the evidence base to enable informed use in adaptive management decisions, 3) use of innovative technologies to more accurately map habitat features and 4) development of wider UK and regional sea scale monitoring pro grammes which align with an ecosystem based approach to the ongoing assessment of marine biodiversity.
1. Introduction Designation of marine protected areas (MPAs) is part of a global approach to balance the sustainable use of marine resources alongside effective biodiversity conservation. In the UK, as part of the EU, the greatest influence on marine conservation is exerted by two policy frameworks, the EU Council Directive (92/43/EEC) on the conservation of natural habitats and of wild fauna and flora (Habitats Directive), and inter-governmental regional seas agreements such as the ‘Convention for the Protection of the Marine Environment of the North-East Atlantic’ (‘the OSPAR Convention’). Implementation of a network of MPAs is one of the main delivery tools for both. The vision for a fully comprehensive and collaborative approach to the governance of Europe’s marine resources is detailed in the European Maritime Policy. Key to this is the establishment of an EU-wide frame work for community actions in the field of marine environmental policy, known as the Marine Strategy Framework Directive (MSFD) (Directive 2008/56/EC). The UK is committed to meet these obligations by
implementing the UK Marine Strategy and, since January 2018, the UK’s 25 Year Environment Plan. Both these commitments have the high-level objective of achieving ‘clean, healthy, safe, productive and biologically diverse oceans and seas’. Establishment of the Marine and Coastal Access Act 2009 (MCAA) and the UK wide Marine Strategy Regulations 2010 transpose the MSFD into UK law and provide the legislative mechanism to achieve this highlevel objective. For the conservation of marine biodiversity specifically, the contribution of an ecologically coherent and well managed network of national Marine Protected Areas, in addition to the existing Natura 2000 network (implemented under the EU Habitats Directive), is intended to provide the legal mechanism to deliver the UKs interna tional and European marine biodiversity commitments (Fig. 1). A key element of this approach is the effective designation and protection of habitats which are considered to be representative of the full range of biodiversity present in our regional seas. In the UK, there are differences in marine legislation between En gland, Wales, Scotland and Northern Ireland due to their devolved
* Corresponding author. E-mail addresses: [email protected] (S. Ware), [email protected] (A.-L. Downie). https://doi.org/10.1016/j.marpol.2019.103717 Received 5 February 2019; Received in revised form 4 October 2019; Accepted 16 October 2019 0308-597X/© 2019 Published by Elsevier Ltd.
Please cite this article as: Suzanne Ware, Anna-Leena Downie, Marine Policy, https://doi.org/10.1016/j.marpol.2019.103717
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administrations. As a result, complexities arise in relation to the different approaches adopted by the devolved administrations to deliver their obligations under the national policy framework [1–3]. However, a common element is their reliance on a systematic approach to conser vation planning and implementation [1], underpinned by specific characteristics including: i) the effective selection of conservation fea tures (species and habitats) as surrogates for biodiversity, ii) adequate representation of those conservation features across the MPA network and iii) implementation of quantifiable conservation objectives (targets) and ability to monitor progress in relation to them [4,5]. As such, a systematic and evidence based approach to MPA designation and monitoring can optimise efficiencies in achieving conservation objec tives, whilst facilitating transparent and flexible decision making that can respond to changing priorities. A potential disadvantage of the approach is the burden of evidence required to reliably inform each stage of the process and its reliance on the effective communication of uncertainty in that evidence to enable its appropriate use by policy makers, managers and regulators.
network to ensure that the range of biodiversity is represented, and that significant reduction or loss of the protected ecosystem processes is mitigated against [6,7]. Key to this initial stage of the designation pro cess is the effective selection of conservation features as surrogates for biodiversity. In general, UK MPA feature selection has been informed by the amalgamation of existing lists of marine features afforded conservation status under other national and international policy. These include Annex I Habitats and Annex II Species (listed under the Habitats Directive) (Appendix, Table 1), and the OSPAR list of threatened and/or declining species and habitats (Appendix, Tables 2 and 4). Nationally important marine conservation features, as defined in the UK Biodi versity Action Plan [8], have also been prioritised for designation as part of the national MPA network. The resultant UK network of national MPAs comprises Marine Conservation Zones (MCZs) and Nature Con servation MPAs (NC MPAs) (Fig. 1) but some features are specific to a marine area governed by the devolved administrations. For example, seamount communities are only represented in Scotland NC MPAs and reefs formed by the honeycomb worm (Sabellaria alveolata) are only represented in England and Wales MCZs (Appendix, Tables 3 and 4). The European Nature Conservation System (EUNIS) is a panEuropean hierarchical habitat classification scheme which was designed to facilitate habitat description and identification of terrestrial, freshwater and marine environments. From a practical perspective, reliance on the systems underlying definitions can hinder the
2. The effective selection of features as surrogates for biodiversity Conservation features have been identified by the UK devolved ad ministrations for designation as protected features within the MPA network. These features must be adequately replicated across the
Fig. 1. Overview of international, European and national policies and conventions, showing those that implement MPAs [Marine Conservation Zones (MCZ), Nature Conservation (NC)] as a delivery tool. 2
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importance and are designated as part of the UK MPA network (Ap pendix, Tables 1–4). Sediment features are typically defined according to often subtle differences in the relative proportion of particle size fractions, derived from the analysis of sediment samples [18]. However, extrapolation of these features identified at a point (grab/core sample) location using the spatially comprehensive acoustic data presents a significant challenge. This is because, whilst fine or coarse sediments have distinctive backscatter strengths and can be readily identified in acoustic data, more closely related sediments (of intermediate granu larity or a mixture of sediment types, as exemplified by EUNIS A5.1 Subtidal Coarse Sediment and A5.4 Subtidal Mixed Sediment) produce less distinct, often overlapping acoustic returns. In the example illustrated in Fig. 2 the acoustic signature of the boulder and cobble category is clearly distinguishable from the gravelly coarse sediment at the East of Haig Fras MCZ. However, the coarse and mixed sediments cannot be acoustically distinguished as their range of backscatter values fully overlap. Similarly, sand and mud have over lapping ranges, and coarser sand (often with some shell fragments), also overlaps with the coarse and mixed backscatter values. At the South Dorset MCZ, there is a less distinct difference in the backscatter ranges of the rock (cobble/boulder) and coarse sediments. The two categories are on a continuum of boulders/cobbles with some gravel, to gravel and pebbles with some cobbles. Practically it is much more difficult to split the two categories and there is scope for a larger margin of error. Certain sediment classes are not separable based on their backscatter strength which is primarily related to the roughness of sediments [19], as even a small proportion of coarse sediment (e.g., gravel) will mask the acoustic return generated by the finer fractions present. Potential im plications for habitat mapping are that polygons may be classified as sediment mosaics, comprising an unknown portion of their individual component sediment types [20]. This presents an element of uncertainty in the context of MPA designation and monitoring, specifically in a) the compliance of the resultant MPA network with the underlying design principles (e.g., representativity and replication) and b) in the outcome of assessments of conservation status to inform management decisions (e.g., spatial extent of habitats), particularly where the component sediments are perceived to differ in their relative sensitivity to a given activity. Similarly, mapping localised, and often ephemeral, biogenic reef features (e.g., Sabellaria spinulosa (ross worm) reef, mussel beds) using acoustic techniques is only reliable where the reef features and sur rounding seabed sediments are texturally distinct [21]. Where this isn’t the case, there will be a greater reliance on seabed imagery to define the distribution and condition of the reef features, albeit at the expense of fully comprehensive spatial coverage (Fig. 3).
implementation of an effective and consistent approach to habitat mapping to support the designation of habitats of conservation impor tance. For example, many of the broadscale habitats which underpin MCZ feature designations are derived from EUNIS level three habitats [1,2] with recent evidence suggesting that these high-level definitions may not effectively represent the full range of biodiversity present across our UK marine sediments [9]. This may lead to certain features and their associated biological communities being over-represented within the MPA network, which may result in resources being misdirected towards their protection. As a consequence, those features which occur less frequently or have not been adequately captured as part of the under lying habitat classifications may be underrepresented and, thus, affor ded insufficient protection. This is demonstrated by the EUNIS definition of biogenic reefs which is currently limited to those formed by specific polychaetes (Sabellaria spp. and Serpula vermicularis), bivalve molluscs (Mytilus edulis, Modiolus modiolus) and cold-water corals (Lophelia per tusa). Application of this definition is insufficiently broad to allow consideration of similarly ecologically important biogenic reef struc tures formed by other benthic taxa (e.g., the polychaete Lanice conchilega and the amphipod Ampelisca spp.) [10,11]. 2.1. Challenges of seabed habitat mapping A systematic approach to MPA designation relies on the availability of sufficiently spatially resolved and accurate seabed habitat maps. Therefore, seabed habitat mapping is a fundamental tool to support all stages of the process from MPA network design planning through to feature condition assessment and subsequent monitoring [12]. This creates a global challenge for marine conservation planning due to a lack of recent and/or fully comprehensive habitat maps for much of our coastal shelf areas and deeper water habitats. In Europe, mapping is underpinned by EUNIS habitat definitions, which aim to improve con sistency in feature classification in the marine, limnetic and terrestrial realm. Application of such classification systems assumes that defined habitat features can be reliably differentiated and mapped using avail able techniques, namely acoustic remote sensing techniques (e.g., mul tibeam echosounder and/or sidescan sonar) in combination with ground truth sampling (e.g., seabed imagery and sediment grab sampling). Whilst this may be appropriate for features that are readily discernible from remote sensing data (e.g., upstanding rock reef) [13], several seabed habitats cannot be reliably mapped using these approaches. 2.1.1. Rock reefs Rock reefs are recognised for their ecological value in supporting high local biodiversity through the provision of suitable substrata for encrusting epifauna, and as refuges for more mobile taxa [14]. The working definition of rock reefs also states that hard substrata covered by thin veneers of mobile sediments should be considered as a reef habitat ‘if the associated fauna are dependent on the hard substrata rather than the overlying sediment’ [15]. Topographically complex, upstanding rock reef can reliably be delineated from surrounding sediments using acoustic remote sensing techniques, but this is not true for other types of reef features. Low lying bedrock features covered by mobile sediment veneers, for example, lack clear definition which renders them indiscernible in the bathymetric data, along with the acoustic backscatter return indicating the presence of sediment habitat at the seabed surface [16]. In this case, greater reliance is placed on the less spatially comprehensive ground truthing data (seabed imagery) to determine whether the biological communities present indicate rock at or close to the sediment surface. This approach requires caution in that the absence of an established attached or encrusting epifaunal community may be the result of human disturbance rather than natural prevailing conditions [17].
2.2. Uncertainty in habitat maps Uncertainty in feature distribution and spatial extent depicted in a map will depend on several factors, including the time elapsed since the mapping survey was carried out (particularly for naturally dynamic environments) and the provenance, quality and quantity (coverage/ density) of the underlying acoustic and ground truth data. The method of habitat map production also contributes to its reliability, with auto mated approaches (such as object-based image analysis (OBIA)) being favoured, due to their repeatability and objectivity in comparison to traditional manual mapping approaches [22]. Ineffective communication of uncertainty in habitat maps can have several consequences for the end users. Overly precautious management measures may be implemented, which includes a portion of additional habitat, thus wasting limited resources on MPA networks that are both unfeasible and inefficient [23]. The converse consequence is the po tential placement of MPAs that under-represent (or omit) certain con servation features resulting in under-protection [24]. Understanding the spatial confidence in a habitat map allows all available information and evidence to be considered in a more informed way and supports the
2.1.2. Sedimentary and biogenic reef features Sedimentary habitat features have been identified as of conservation 3
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Fig. 2. Backscatter return (dB) produced by comparable sediment types (as defined by the modified Folk trigon) (Long, 2001) at two sites on the UK continental shelf (left: East of Haig Fras MCZ, located off Cornwall in the Celtic Sea; right: South Dorset MCZ, located in the eastern English Channel).
Fig. 3. Illustration of high similarity in single sidescan sonar lines between (a) characteristic Sabellaria spinulosa reef, and (b) non-reef, coarse habitat (left – images of the acoustic signature for both sites, right – associated seabed image of the site at the position indicated by the red dot). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)
adaptive implementation of management measures based on feature-specific confidence [25] which can be increased over time with additional monitoring effort.
the two. Whilst pressure/feature relationships are well known for most established conservation features [27], key gaps remain in our under standing of the sensitivity of newly defined features (e.g., broadscale habitats protected as part of the MPAs) and also the cumulative impacts of both current and emergent pressures in the context of natural vari ability. In addition, the high variability of biological diversity associated with a given broadscale habitat feature hinders the ability to effectively determine a reliable ‘sensitivity score’ for that feature at a national scale. This, in turn, presents additional challenges in forecasting future changes in feature vulnerability to take into account longer term impacts associated with, for example, climate change. As a result, vulnerability assessment typically adopts a precautionary approach to mitigate against this uncertainty. Direct assessment and monitoring are based on observations of the physical structure of the feature itself (e.g., biogenic and rock reefs) and the structural and functional characteristics of its associated biological
3. Implementation of quantifiable conservation objectives and monitoring and assessment of conservation status The latter stage of systematic conservation planning is the moni toring and assessment of features to infer their conservation status (or ecological condition) and to inform effective management decisions. This is traditionally carried out using a vulnerability assessment [26] and/or direct observation. A vulnerability assessment predicts the con servation status of a feature based on its distribution and extent, in combination with the spatial footprint of human pressures to which the feature is perceived to be sensitive. Confidence in the outcome of the assessment relies on a robust understanding of the relationship between 4
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communities [28]. This approach requires robust understanding of the relationship between the feature and relevant pressures, but more spe cifically of the physical and biological characteristics of a feature which indicate its favourable conservation status, along with thresholds beyond which a deterioration is considered unacceptable. According to the Habitats Directive (1992), a habitat feature is at favourable conservation status when ‘its natural range and areas it covers within that range are stable or increasing, the specific structure and functions which are necessary for its long-term maintenance exist and are likely to continue to exist for the foreseeable future and the conservation status of its typical species is favourable’. Similar working definitions of favourable conservation status underpin the assessment process for features designated under UK national legislation [1]. To assess conservation status according to these definitions, it must be possible to accurately determine the spatial extent of habitat features so that any changes resulting from a human activity can be reliably detected. In practise, this is often hindered by our inability to produce sufficiently resolute and accurate habitat maps (at the relevant spatial and temporal scales) to delineate human induced change from natural perturbations. In addition to effective mapping of habitat features, a thorough un derstanding of the features’ ecology, in the context of natural variability, is required for any departure from (or recovery towards) favourable conservation status to be detected [29]. Indicators of favourable con servation status are well understood for established subtidal habitat features such as biogenic reefs [30] and maerl beds [29] and long-term monitoring of maerl beds has provided time-series data to allow the development of ecologically meaningful measures and thresholds of feature condition [31]. However, for more recently defined habitat features, where long-term time series data do not exist, a departure from favourable conservation status is less straightforward to detect and the development of reliable indicators of condition (particularly those which exhibit high levels of natural variability) presents a real chal lenge. Shallow tide-swept and highly dynamic sedimentary broadscale habitats have associated biological communities that are well adapted and resilient to high rates of mortality [32] for example. However, the significance of additional anthropogenic disturbance on their condition (and ecological integrity) is not yet fully understood [29].
use of the EUNIS habitat classification scheme could be adapted to ensure that the full range of biological diversity associated with MPA conservation features is more comprehensively captured. In addition, current limitations in seabed mapping could be overcome by imple menting innovative approaches and new technologies. Autonomous underwater vehicles (AUVs), for example, can be used to map localised and acoustically indistinct features (such as biogenic reefs or seagrass beds). Recent successes have been reported using AUVs and remotely operated vehicles (ROVs) to acquire seabed imagery used to create highly accurate, full coverage photo mosaics of the seabed [33]. How ever, challenges remain around how to effectively incorporate these new types of data into the existing evidence base acquired using more traditional techniques. There may also be an opportunity to incorporate greater flexibility in the designation process to allow habitat definitions to be widened (e.g., biogenic reef), thereby ensuring that all examples of these feature types are considered and included as part of the developing UK MPA network. Similarly, monitoring and assessment processes (e.g., operational indi cator development) could be improved to align with an ecosystem approach. For example, the current lists of indicators defined to meet obligations under the EU Marine Strategy Framework Directive (MSFD) (both pressure-based and ecological) could be tailored to better align with designated conservation features across the UK MPA network and the priority human activities to which they are sensitive. Despite the challenges identified, progression of an evidence based, systematic approach to MPA designation and monitoring is still considered key in ensuring optimal results for marine conservation. An ecosystem approach for managing the marine environment is funda mental to the objectives outlined in the 25 Year Environment plan and the Fisheries White Paper. Going forward, MPA specific monitoring and assessment must be incorporated into the developing ecosystem approach to monitoring (comprising fishery, biodiversity and wider environmental monitoring) to effectively deliver scientifically robust and cost-effective management of UK seas into the future. As part of this approach, future monitoring of MPAs will benefit from consideration of all ecosystem components (including the pelagic realm) as opposed to a continuation of the current focus specifically on benthic habitats and a subset of associated species.
4. Conclusions
Acknowledgements
Whilst we have identified some of the operational challenges asso ciated with collating the necessary evidence base to support MPA designation, monitoring and assessment, there are future opportunities to refine the process and act on lessons learned to date. For example, the
This work was funded by Cefas, United Kingdom. The authors would like to thank Cefas staff including Michaela Schratzberger, Stephen Malcolm, Joanna Murray and Georg Englehard for comment and review. We are grateful for constructive feedback provided by Defra.
Appendix
Table 1 UK marine habitats (and descriptions) listed in Annex I of the Habitats Directive (European Commission, 1992). Annex I Habitat Sandbanks which are slightly covered by seawater all the time Estuaries Mudflats and sandflats not covered by seawater at low tide Coastal lagoons Large shallow inlets and bays Reefs Submarine structures made by leaking gases Annual vegetation of drift lines Salicornia and other annuals colonising mud and sand Spartina swards (Spartinion maritimae) Atlantic salt meadows (Glauco-Puccinellietalia maritimae) Mediterranean and thermo-Atlantic halophilous scrubs (Sarcocornetea fruticosi) Submerged or partially submerged sea caves
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Table 2 EU marine features included in the OSPAR List of Threatened and/or Declining Species and Habitats (OSPAR Convention, 1998). OSPAR Threatened & Declining Habitats Coral gardens Deep-sea sponge aggregations Intertidal Mytilus edulis beds on mixed and sandy sediments Intertidal mudflats Littoral chalk communities Lophelia pertusa reefs Maerl beds Modiolus modiolus beds Ostrea edulis beds Sabellaria spinulosa reefs Seapen and burrowing megafauna communities Zostera beds
Table 3 List of marine broadscale habitat features (EUNIS Level 3) to be considered for inclusion for designation of MCZs (England & Wales). 1 indicates the feature is included in the Habitats Directive Annex I list and 2 indicates the feature is included in the OSPAR List of Threatened and/or Declining Species and Habitats. MCZs (England & Wales) Intertidal Rock A1.1 High energy intertidal rock1 A1.2 Moderate energy intertidal rock1 A1.3 Low energy intertidal rock1 Intertidal Sediments A2.1 Intertidal coarse sediment A2.2 Intertidal sand and muddy sand A2.3 Intertidal mud A2.4 Intertidal mixed sediments A2.5 Coastal saltmarshes and saline reed beds1 A2.6 Intertidal sediments dominated by aquatic angiosperms A2.7 Intertidal biogenic reefs12
Circalittoral Rock A4.1 High energy circalittoral rock1 A4.2 Moderate energy circalittoral rock1 A4.3 Low energy circalittoral rock1 Subtidal Sediments A5.1 Subtidal coarse sediment A5.2 Subtidal sand A5.3 Subtidal mud A5.4 Subtidal mixed sediments A5.5 Subtidal macrophyte dominated sediment A5.6 Subtidal biogenic reef12 Deep Seabed A6 Deep seabed
Infralittoral Rock A3.1 High energy infralittoral rock1 A3.2 Moderate energy infralittoral rock1 A3.3 low energy infralittoral rock1
Table 4 List of UK marine habitat features prioritised by UK devolved administrations for inclusion for designation within the national MPA network. Habitat features are cross referenced with comparable features listed in Annex I of the Habitats Directive and the OSPAR T&D as appropriate. 1 indicates the feature is included in the Habitats Directive Annex I list and 2 indicates the feature is included in the OSPAR List of Threatened and/or Declining Species and Habitats. Equivalent features for each of the three devolved administrations are in the same row of the table. MCZs (England & Wales)
MCZs (Northern Ireland)
NC MPAs (Scotland)
Habitat Features of Conservation Importance (FOCI) ✓ Blue Mussel Beds (inc. Intertidal Beds on Mixed and Sandy Sediments)12 ✓ Maerl Beds2 ✓ Horse Mussel (Modiolus modiolus) Beds12 ✓ Native Oyster (Ostrea edulis) Beds2 ✓ Seagrass beds2 ✓ Estuarine Rocky Habitats ✓ Fragile Sponge and Anthozoan Communities on Subtidal Rocky Habitats ✓ Cold-Water Coral Reefs2 ✓ Sea-Pen and Burrowing Megafauna Communities2 ✓ Deep-Sea Sponge Aggregations2 ✓ Coral Gardens2 ✓ File Shell Beds ✓ Intertidal Underboulder Communities ✓ Littoral Chalk Communities2 ✓ Peat and Clay Exposures ✓ Honeycomb Worm (Sabellaria alveolata) Reefs1 ✓ Ross Worm (Sabellaria spinulosa) Reefs12 ✓ Sheltered Muddy Gravels ✓ Subtidal Chalk ✓ Tide-Swept Channels x x
Priority Marine Features (PMF) Habitats ✓ Blue Mussel Beds (inc. Intertidal Beds on Mixed and Sandy Sediments)12 ✓ Maerl Beds2 ✓ Horse Mussel (Modiolus modiolus) Beds12 ✓ Ostrea edulis Beds2 ✓ Seagrass Beds2 ✓ Estuarine Rocky Habitats ✓ Fragile Sponge and Anthozoan Communities on Subtidal Rocky Habitats ✓ Cold-Water Coral Reefs2 ✓ Sea-Pen and Burrowing Megafauna Communities2 x x x x x x x x x x x ✓Mud Habitats in Deep Water ✓ Stable Sand with Associated Fauna
NC MPA Search Features ✓ Blue Mussel Beds12 ✓ Maerl Beds2 ✓ Horse Mussel Beds12 ✓ Native Oysters2 ✓ Seagrass Beds2 x x x x ✓ Deep-Sea Sponge Aggregations2 ✓ Coral Gardens2 x x x x x x x x x x x (continued on next page)
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Table 4 (continued ) MCZs (England & Wales)
MCZs (Northern Ireland)
NC MPAs (Scotland)
x x x x x x
x x x x x x
x x x x x x
x x x x x x
x
x
✓ Subtidal Sands and Gravels (Offshore) ✓ Carbonate Mound Communities ✓ Burrowed Mud ✓ Flame Shell Beds ✓ Inshore deep mud with burrowing urchins ✓ Kelp and Seaweed Communities on sublittoral Sediment ✓ Low or Variable Salinity Habitats ✓ Northern Sea Fan and Sponge Communities ✓ Offshore Deep Sea Muds ✓ Sea Loch Egg Wrack Beds ✓ Seamount Communities ✓ Shallow Tide-Swept Coarse Sands with Burrowing Bivalves ✓ Tide-Swept Algal Communities
Appendix A. Supplementary data Supplementary data to this article can be found online at https://doi.org/10.1016/j.marpol.2019.103717.
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[1] Natural England, J.N.C.C. the, Marine Conservation Zone Project Ecological Network Guidance, 2010, p. 144. http://jncc.defra.gov.uk/pdf/100705_ENG_v10. pdf. [2] Marine Scotland, Marine Protected Areas in Scotland’s Seas: Guidelines on the Selection of MPAs and Development of the MPA Network, 2011, p. 73. htt p://www.gov.scot/Resource/Doc/295194/0114024.pdf. [3] DOENI, A Draft Strategy for the Protection of Marine Protected Areas in the Northern Ireland Inshore Region 2013, 2013, p. 39. https://www.doeni.gov. uk/publications/strategy-marine-protected-areas-northern-ireland-inshore-region. [4] C.R. Margules, R.L. Pressey, Systematic conservation planning, Nature 405 (2000) 243–253. [5] J.A. Ardron, M.R. Clark, A.J. Penney, T.F. Hourigan, A.A. Rowden, P.K. Dunstan, L. Watling, S.J., A systematic approach towards the identification and protection of vulnerable marine ecosystems, Mar. Policy 49 (2013) 146–154. [6] M. Young, M. Carr, Assessment of habitat representation across a network of marine protected areas with implications for the spatial design of monitoring, PLoS One 10 (3) (2015), e0116200, https://doi.org/10.1371/journal.pone.0116200. [7] P.R. Sutcliffe, C.J. Klein, C.R. Pitcher, H.P. Possingham, The effectiveness of marine reserve systems constructed using different surrogates of biodiversity, Conserv. Biol. 29 (3) (2015) 657–667. [8] D.W. Connor, J. Breen, A. Champion, P.M. Gilliland, D. Huggett, C. Johnston, D. Laffoley, M. Shardlow, Rationale and Criteria for the Identification of Nationally Important Marine Nature Conservation Features and Areas in the UK, 2002. Version 02.11. 2002. [9] K.M. Cooper, S.G. Bolam, A.-L. Downie, J. Barry, Biological-based habitat classification approaches promote cost-efficient monitoring: an example using seabed assemblages, J. Appl. Ecol. 56 (2019) 1085–1098. [10] M. Rabaut, M. Vincx, S. Degraer, Do Lanice conchilega (sandmason) aggregations classify as reefs? Quantifying habitat modifying effects, Helgol. Mar. Res. 63 (1) (2009) 37–46. [11] J.C. Dauvin, S. Zouhiri, Suprabenthic crustacean fauna of a dense Ampelisca community from the English Channel, J. Mar. Biol. Assoc. U. K. 76 (1996) 909–929. [12] C.B. Cogan, B.J. Todd, P. Lawton, T.T. Noji, The role of marine habitat mapping in ecosystem-based management, ICES (Int. Counc. Explor. Sea) J. Mar. Sci. 66 (2009) 2033–2042. [13] Defra, Coordination of the Defra MCZ Data Collection Programme, Report No 17: Isles of Scilly Sites: Bristow to the Stones rMCZ Post-Survey Site Report, 2014. http://randd.defra.gov.uk/Default.aspx?Menu¼Menu&Module¼More &Location¼None&ProjectID¼18983&FromSearch¼Y&Publisher¼1&SearchTe xt¼mcz&SortString¼ProjectCode&SortOrder¼Asc&Paging¼10#Description. [14] A. S� anchez-Rodrigues, O. Aburton-Oropeza, B. Erisman, V.M. Jim� enez-Esquivel, Rocky reefs: preserving biodiversity for the benefit of the communities in the aquarium of the world, in: N. Narchi, L. Price (Eds.), Ethnobiology of Corals and Coral Reefs. Ethnobiology, Springer, Cham, 2015. [15] R. Irving, The identification of the main characteristics of stony reef habitats under the Habitats Directive, JNCC Report No. 432, 2009, p. 44. [16] J.W.C. James, B. Pearce, R.A. Coggan, S.H.L. Arnott, R. Clark, J.F. Plim, J. Pinnion, N. Bigourdan, The South coast regional environmental characterisation, Br. Geol. Surv. (2010) 249 (OR/09/051), http://nora.nerc.ac.uk/13120/. [17] E.V. Sheehan, T.F. Stevens, S.C. Gall, S.L. Cousens, M.J. Attrill, Recovery of a temperate reef assemblage in a marine protected area following the exclusion of towed demersal fishing, PLoS One 8 (2013), e83883.
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Contents lists available at ScienceDirect
Marine Policy journal homepage: http://www.elsevier.com/locate/marpol
Challenges of habitat mapping to inform marine protected area (MPA) designation and monitoring: An operational perspective Suzanne Ware *, Anna-Leena Downie Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft Laboratory, Pakefield Road, Lowestoft, Suffolk, England, NR33 0HT, UK
A R T I C L E I N F O
A B S T R A C T
Keywords: Ecosystem Habitats Indicators Mapping Monitoring Biodiversity
The UK has adopted a feature-based approach to MPA designation and monitoring to meet international and national obligations. Despite operational challenges, this approach is considered key to optimising conservation outcomes whilst making efficient use of limited resources. Drawing on lessons learnt from the UK’s MPA Pro gramme we discuss the practical issues which arise from: i) effective selection of conservation features identified as surrogates for biodiversity, ii) adequacy of feature representation across the MPA network and iii) imple mentation of quantifiable conservation objectives and ability to monitor progress in relation to them [4,5]. There is recognition that high-level feature surrogates adopted for MPA designation may not adequately represent the full range of biodiversity present across UK marine habitats, and several of these features are indiscernible using acoustic mapping techniques. This results in our inability to accurately map their distribution and extent. Additionally, monitoring progress in relation to conservation targets is hampered by a lack of reliable indicators to assess change in their ecological status. Recommendations for the optimisation of MPA designation and monitoring using a systematic, evidence based approach are provided. These include: 1) flexibility in feature classifications to allow additional features to be designated as required, 2) communication of limitations in the evidence base to enable informed use in adaptive management decisions, 3) use of innovative technologies to more accurately map habitat features and 4) development of wider UK and regional sea scale monitoring pro grammes which align with an ecosystem based approach to the ongoing assessment of marine biodiversity.
1. Introduction Designation of marine protected areas (MPAs) is part of a global approach to balance the sustainable use of marine resources alongside effective biodiversity conservation. In the UK, as part of the EU, the greatest influence on marine conservation is exerted by two policy frameworks, the EU Council Directive (92/43/EEC) on the conservation of natural habitats and of wild fauna and flora (Habitats Directive), and inter-governmental regional seas agreements such as the ‘Convention for the Protection of the Marine Environment of the North-East Atlantic’ (‘the OSPAR Convention’). Implementation of a network of MPAs is one of the main delivery tools for both. The vision for a fully comprehensive and collaborative approach to the governance of Europe’s marine resources is detailed in the European Maritime Policy. Key to this is the establishment of an EU-wide frame work for community actions in the field of marine environmental policy, known as the Marine Strategy Framework Directive (MSFD) (Directive 2008/56/EC). The UK is committed to meet these obligations by
implementing the UK Marine Strategy and, since January 2018, the UK’s 25 Year Environment Plan. Both these commitments have the high-level objective of achieving ‘clean, healthy, safe, productive and biologically diverse oceans and seas’. Establishment of the Marine and Coastal Access Act 2009 (MCAA) and the UK wide Marine Strategy Regulations 2010 transpose the MSFD into UK law and provide the legislative mechanism to achieve this highlevel objective. For the conservation of marine biodiversity specifically, the contribution of an ecologically coherent and well managed network of national Marine Protected Areas, in addition to the existing Natura 2000 network (implemented under the EU Habitats Directive), is intended to provide the legal mechanism to deliver the UKs interna tional and European marine biodiversity commitments (Fig. 1). A key element of this approach is the effective designation and protection of habitats which are considered to be representative of the full range of biodiversity present in our regional seas. In the UK, there are differences in marine legislation between En gland, Wales, Scotland and Northern Ireland due to their devolved
* Corresponding author. E-mail addresses: [email protected] (S. Ware), [email protected] (A.-L. Downie). https://doi.org/10.1016/j.marpol.2019.103717 Received 5 February 2019; Received in revised form 4 October 2019; Accepted 16 October 2019 0308-597X/© 2019 Published by Elsevier Ltd.
Please cite this article as: Suzanne Ware, Anna-Leena Downie, Marine Policy, https://doi.org/10.1016/j.marpol.2019.103717
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administrations. As a result, complexities arise in relation to the different approaches adopted by the devolved administrations to deliver their obligations under the national policy framework [1–3]. However, a common element is their reliance on a systematic approach to conser vation planning and implementation [1], underpinned by specific characteristics including: i) the effective selection of conservation fea tures (species and habitats) as surrogates for biodiversity, ii) adequate representation of those conservation features across the MPA network and iii) implementation of quantifiable conservation objectives (targets) and ability to monitor progress in relation to them [4,5]. As such, a systematic and evidence based approach to MPA designation and monitoring can optimise efficiencies in achieving conservation objec tives, whilst facilitating transparent and flexible decision making that can respond to changing priorities. A potential disadvantage of the approach is the burden of evidence required to reliably inform each stage of the process and its reliance on the effective communication of uncertainty in that evidence to enable its appropriate use by policy makers, managers and regulators.
network to ensure that the range of biodiversity is represented, and that significant reduction or loss of the protected ecosystem processes is mitigated against [6,7]. Key to this initial stage of the designation pro cess is the effective selection of conservation features as surrogates for biodiversity. In general, UK MPA feature selection has been informed by the amalgamation of existing lists of marine features afforded conservation status under other national and international policy. These include Annex I Habitats and Annex II Species (listed under the Habitats Directive) (Appendix, Table 1), and the OSPAR list of threatened and/or declining species and habitats (Appendix, Tables 2 and 4). Nationally important marine conservation features, as defined in the UK Biodi versity Action Plan [8], have also been prioritised for designation as part of the national MPA network. The resultant UK network of national MPAs comprises Marine Conservation Zones (MCZs) and Nature Con servation MPAs (NC MPAs) (Fig. 1) but some features are specific to a marine area governed by the devolved administrations. For example, seamount communities are only represented in Scotland NC MPAs and reefs formed by the honeycomb worm (Sabellaria alveolata) are only represented in England and Wales MCZs (Appendix, Tables 3 and 4). The European Nature Conservation System (EUNIS) is a panEuropean hierarchical habitat classification scheme which was designed to facilitate habitat description and identification of terrestrial, freshwater and marine environments. From a practical perspective, reliance on the systems underlying definitions can hinder the
2. The effective selection of features as surrogates for biodiversity Conservation features have been identified by the UK devolved ad ministrations for designation as protected features within the MPA network. These features must be adequately replicated across the
Fig. 1. Overview of international, European and national policies and conventions, showing those that implement MPAs [Marine Conservation Zones (MCZ), Nature Conservation (NC)] as a delivery tool. 2
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importance and are designated as part of the UK MPA network (Ap pendix, Tables 1–4). Sediment features are typically defined according to often subtle differences in the relative proportion of particle size fractions, derived from the analysis of sediment samples [18]. However, extrapolation of these features identified at a point (grab/core sample) location using the spatially comprehensive acoustic data presents a significant challenge. This is because, whilst fine or coarse sediments have distinctive backscatter strengths and can be readily identified in acoustic data, more closely related sediments (of intermediate granu larity or a mixture of sediment types, as exemplified by EUNIS A5.1 Subtidal Coarse Sediment and A5.4 Subtidal Mixed Sediment) produce less distinct, often overlapping acoustic returns. In the example illustrated in Fig. 2 the acoustic signature of the boulder and cobble category is clearly distinguishable from the gravelly coarse sediment at the East of Haig Fras MCZ. However, the coarse and mixed sediments cannot be acoustically distinguished as their range of backscatter values fully overlap. Similarly, sand and mud have over lapping ranges, and coarser sand (often with some shell fragments), also overlaps with the coarse and mixed backscatter values. At the South Dorset MCZ, there is a less distinct difference in the backscatter ranges of the rock (cobble/boulder) and coarse sediments. The two categories are on a continuum of boulders/cobbles with some gravel, to gravel and pebbles with some cobbles. Practically it is much more difficult to split the two categories and there is scope for a larger margin of error. Certain sediment classes are not separable based on their backscatter strength which is primarily related to the roughness of sediments [19], as even a small proportion of coarse sediment (e.g., gravel) will mask the acoustic return generated by the finer fractions present. Potential im plications for habitat mapping are that polygons may be classified as sediment mosaics, comprising an unknown portion of their individual component sediment types [20]. This presents an element of uncertainty in the context of MPA designation and monitoring, specifically in a) the compliance of the resultant MPA network with the underlying design principles (e.g., representativity and replication) and b) in the outcome of assessments of conservation status to inform management decisions (e.g., spatial extent of habitats), particularly where the component sediments are perceived to differ in their relative sensitivity to a given activity. Similarly, mapping localised, and often ephemeral, biogenic reef features (e.g., Sabellaria spinulosa (ross worm) reef, mussel beds) using acoustic techniques is only reliable where the reef features and sur rounding seabed sediments are texturally distinct [21]. Where this isn’t the case, there will be a greater reliance on seabed imagery to define the distribution and condition of the reef features, albeit at the expense of fully comprehensive spatial coverage (Fig. 3).
implementation of an effective and consistent approach to habitat mapping to support the designation of habitats of conservation impor tance. For example, many of the broadscale habitats which underpin MCZ feature designations are derived from EUNIS level three habitats [1,2] with recent evidence suggesting that these high-level definitions may not effectively represent the full range of biodiversity present across our UK marine sediments [9]. This may lead to certain features and their associated biological communities being over-represented within the MPA network, which may result in resources being misdirected towards their protection. As a consequence, those features which occur less frequently or have not been adequately captured as part of the under lying habitat classifications may be underrepresented and, thus, affor ded insufficient protection. This is demonstrated by the EUNIS definition of biogenic reefs which is currently limited to those formed by specific polychaetes (Sabellaria spp. and Serpula vermicularis), bivalve molluscs (Mytilus edulis, Modiolus modiolus) and cold-water corals (Lophelia per tusa). Application of this definition is insufficiently broad to allow consideration of similarly ecologically important biogenic reef struc tures formed by other benthic taxa (e.g., the polychaete Lanice conchilega and the amphipod Ampelisca spp.) [10,11]. 2.1. Challenges of seabed habitat mapping A systematic approach to MPA designation relies on the availability of sufficiently spatially resolved and accurate seabed habitat maps. Therefore, seabed habitat mapping is a fundamental tool to support all stages of the process from MPA network design planning through to feature condition assessment and subsequent monitoring [12]. This creates a global challenge for marine conservation planning due to a lack of recent and/or fully comprehensive habitat maps for much of our coastal shelf areas and deeper water habitats. In Europe, mapping is underpinned by EUNIS habitat definitions, which aim to improve con sistency in feature classification in the marine, limnetic and terrestrial realm. Application of such classification systems assumes that defined habitat features can be reliably differentiated and mapped using avail able techniques, namely acoustic remote sensing techniques (e.g., mul tibeam echosounder and/or sidescan sonar) in combination with ground truth sampling (e.g., seabed imagery and sediment grab sampling). Whilst this may be appropriate for features that are readily discernible from remote sensing data (e.g., upstanding rock reef) [13], several seabed habitats cannot be reliably mapped using these approaches. 2.1.1. Rock reefs Rock reefs are recognised for their ecological value in supporting high local biodiversity through the provision of suitable substrata for encrusting epifauna, and as refuges for more mobile taxa [14]. The working definition of rock reefs also states that hard substrata covered by thin veneers of mobile sediments should be considered as a reef habitat ‘if the associated fauna are dependent on the hard substrata rather than the overlying sediment’ [15]. Topographically complex, upstanding rock reef can reliably be delineated from surrounding sediments using acoustic remote sensing techniques, but this is not true for other types of reef features. Low lying bedrock features covered by mobile sediment veneers, for example, lack clear definition which renders them indiscernible in the bathymetric data, along with the acoustic backscatter return indicating the presence of sediment habitat at the seabed surface [16]. In this case, greater reliance is placed on the less spatially comprehensive ground truthing data (seabed imagery) to determine whether the biological communities present indicate rock at or close to the sediment surface. This approach requires caution in that the absence of an established attached or encrusting epifaunal community may be the result of human disturbance rather than natural prevailing conditions [17].
2.2. Uncertainty in habitat maps Uncertainty in feature distribution and spatial extent depicted in a map will depend on several factors, including the time elapsed since the mapping survey was carried out (particularly for naturally dynamic environments) and the provenance, quality and quantity (coverage/ density) of the underlying acoustic and ground truth data. The method of habitat map production also contributes to its reliability, with auto mated approaches (such as object-based image analysis (OBIA)) being favoured, due to their repeatability and objectivity in comparison to traditional manual mapping approaches [22]. Ineffective communication of uncertainty in habitat maps can have several consequences for the end users. Overly precautious management measures may be implemented, which includes a portion of additional habitat, thus wasting limited resources on MPA networks that are both unfeasible and inefficient [23]. The converse consequence is the po tential placement of MPAs that under-represent (or omit) certain con servation features resulting in under-protection [24]. Understanding the spatial confidence in a habitat map allows all available information and evidence to be considered in a more informed way and supports the
2.1.2. Sedimentary and biogenic reef features Sedimentary habitat features have been identified as of conservation 3
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Fig. 2. Backscatter return (dB) produced by comparable sediment types (as defined by the modified Folk trigon) (Long, 2001) at two sites on the UK continental shelf (left: East of Haig Fras MCZ, located off Cornwall in the Celtic Sea; right: South Dorset MCZ, located in the eastern English Channel).
Fig. 3. Illustration of high similarity in single sidescan sonar lines between (a) characteristic Sabellaria spinulosa reef, and (b) non-reef, coarse habitat (left – images of the acoustic signature for both sites, right – associated seabed image of the site at the position indicated by the red dot). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)
adaptive implementation of management measures based on feature-specific confidence [25] which can be increased over time with additional monitoring effort.
the two. Whilst pressure/feature relationships are well known for most established conservation features [27], key gaps remain in our under standing of the sensitivity of newly defined features (e.g., broadscale habitats protected as part of the MPAs) and also the cumulative impacts of both current and emergent pressures in the context of natural vari ability. In addition, the high variability of biological diversity associated with a given broadscale habitat feature hinders the ability to effectively determine a reliable ‘sensitivity score’ for that feature at a national scale. This, in turn, presents additional challenges in forecasting future changes in feature vulnerability to take into account longer term impacts associated with, for example, climate change. As a result, vulnerability assessment typically adopts a precautionary approach to mitigate against this uncertainty. Direct assessment and monitoring are based on observations of the physical structure of the feature itself (e.g., biogenic and rock reefs) and the structural and functional characteristics of its associated biological
3. Implementation of quantifiable conservation objectives and monitoring and assessment of conservation status The latter stage of systematic conservation planning is the moni toring and assessment of features to infer their conservation status (or ecological condition) and to inform effective management decisions. This is traditionally carried out using a vulnerability assessment [26] and/or direct observation. A vulnerability assessment predicts the con servation status of a feature based on its distribution and extent, in combination with the spatial footprint of human pressures to which the feature is perceived to be sensitive. Confidence in the outcome of the assessment relies on a robust understanding of the relationship between 4
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communities [28]. This approach requires robust understanding of the relationship between the feature and relevant pressures, but more spe cifically of the physical and biological characteristics of a feature which indicate its favourable conservation status, along with thresholds beyond which a deterioration is considered unacceptable. According to the Habitats Directive (1992), a habitat feature is at favourable conservation status when ‘its natural range and areas it covers within that range are stable or increasing, the specific structure and functions which are necessary for its long-term maintenance exist and are likely to continue to exist for the foreseeable future and the conservation status of its typical species is favourable’. Similar working definitions of favourable conservation status underpin the assessment process for features designated under UK national legislation [1]. To assess conservation status according to these definitions, it must be possible to accurately determine the spatial extent of habitat features so that any changes resulting from a human activity can be reliably detected. In practise, this is often hindered by our inability to produce sufficiently resolute and accurate habitat maps (at the relevant spatial and temporal scales) to delineate human induced change from natural perturbations. In addition to effective mapping of habitat features, a thorough un derstanding of the features’ ecology, in the context of natural variability, is required for any departure from (or recovery towards) favourable conservation status to be detected [29]. Indicators of favourable con servation status are well understood for established subtidal habitat features such as biogenic reefs [30] and maerl beds [29] and long-term monitoring of maerl beds has provided time-series data to allow the development of ecologically meaningful measures and thresholds of feature condition [31]. However, for more recently defined habitat features, where long-term time series data do not exist, a departure from favourable conservation status is less straightforward to detect and the development of reliable indicators of condition (particularly those which exhibit high levels of natural variability) presents a real chal lenge. Shallow tide-swept and highly dynamic sedimentary broadscale habitats have associated biological communities that are well adapted and resilient to high rates of mortality [32] for example. However, the significance of additional anthropogenic disturbance on their condition (and ecological integrity) is not yet fully understood [29].
use of the EUNIS habitat classification scheme could be adapted to ensure that the full range of biological diversity associated with MPA conservation features is more comprehensively captured. In addition, current limitations in seabed mapping could be overcome by imple menting innovative approaches and new technologies. Autonomous underwater vehicles (AUVs), for example, can be used to map localised and acoustically indistinct features (such as biogenic reefs or seagrass beds). Recent successes have been reported using AUVs and remotely operated vehicles (ROVs) to acquire seabed imagery used to create highly accurate, full coverage photo mosaics of the seabed [33]. How ever, challenges remain around how to effectively incorporate these new types of data into the existing evidence base acquired using more traditional techniques. There may also be an opportunity to incorporate greater flexibility in the designation process to allow habitat definitions to be widened (e.g., biogenic reef), thereby ensuring that all examples of these feature types are considered and included as part of the developing UK MPA network. Similarly, monitoring and assessment processes (e.g., operational indi cator development) could be improved to align with an ecosystem approach. For example, the current lists of indicators defined to meet obligations under the EU Marine Strategy Framework Directive (MSFD) (both pressure-based and ecological) could be tailored to better align with designated conservation features across the UK MPA network and the priority human activities to which they are sensitive. Despite the challenges identified, progression of an evidence based, systematic approach to MPA designation and monitoring is still considered key in ensuring optimal results for marine conservation. An ecosystem approach for managing the marine environment is funda mental to the objectives outlined in the 25 Year Environment plan and the Fisheries White Paper. Going forward, MPA specific monitoring and assessment must be incorporated into the developing ecosystem approach to monitoring (comprising fishery, biodiversity and wider environmental monitoring) to effectively deliver scientifically robust and cost-effective management of UK seas into the future. As part of this approach, future monitoring of MPAs will benefit from consideration of all ecosystem components (including the pelagic realm) as opposed to a continuation of the current focus specifically on benthic habitats and a subset of associated species.
4. Conclusions
Acknowledgements
Whilst we have identified some of the operational challenges asso ciated with collating the necessary evidence base to support MPA designation, monitoring and assessment, there are future opportunities to refine the process and act on lessons learned to date. For example, the
This work was funded by Cefas, United Kingdom. The authors would like to thank Cefas staff including Michaela Schratzberger, Stephen Malcolm, Joanna Murray and Georg Englehard for comment and review. We are grateful for constructive feedback provided by Defra.
Appendix
Table 1 UK marine habitats (and descriptions) listed in Annex I of the Habitats Directive (European Commission, 1992). Annex I Habitat Sandbanks which are slightly covered by seawater all the time Estuaries Mudflats and sandflats not covered by seawater at low tide Coastal lagoons Large shallow inlets and bays Reefs Submarine structures made by leaking gases Annual vegetation of drift lines Salicornia and other annuals colonising mud and sand Spartina swards (Spartinion maritimae) Atlantic salt meadows (Glauco-Puccinellietalia maritimae) Mediterranean and thermo-Atlantic halophilous scrubs (Sarcocornetea fruticosi) Submerged or partially submerged sea caves
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Table 2 EU marine features included in the OSPAR List of Threatened and/or Declining Species and Habitats (OSPAR Convention, 1998). OSPAR Threatened & Declining Habitats Coral gardens Deep-sea sponge aggregations Intertidal Mytilus edulis beds on mixed and sandy sediments Intertidal mudflats Littoral chalk communities Lophelia pertusa reefs Maerl beds Modiolus modiolus beds Ostrea edulis beds Sabellaria spinulosa reefs Seapen and burrowing megafauna communities Zostera beds
Table 3 List of marine broadscale habitat features (EUNIS Level 3) to be considered for inclusion for designation of MCZs (England & Wales). 1 indicates the feature is included in the Habitats Directive Annex I list and 2 indicates the feature is included in the OSPAR List of Threatened and/or Declining Species and Habitats. MCZs (England & Wales) Intertidal Rock A1.1 High energy intertidal rock1 A1.2 Moderate energy intertidal rock1 A1.3 Low energy intertidal rock1 Intertidal Sediments A2.1 Intertidal coarse sediment A2.2 Intertidal sand and muddy sand A2.3 Intertidal mud A2.4 Intertidal mixed sediments A2.5 Coastal saltmarshes and saline reed beds1 A2.6 Intertidal sediments dominated by aquatic angiosperms A2.7 Intertidal biogenic reefs12
Circalittoral Rock A4.1 High energy circalittoral rock1 A4.2 Moderate energy circalittoral rock1 A4.3 Low energy circalittoral rock1 Subtidal Sediments A5.1 Subtidal coarse sediment A5.2 Subtidal sand A5.3 Subtidal mud A5.4 Subtidal mixed sediments A5.5 Subtidal macrophyte dominated sediment A5.6 Subtidal biogenic reef12 Deep Seabed A6 Deep seabed
Infralittoral Rock A3.1 High energy infralittoral rock1 A3.2 Moderate energy infralittoral rock1 A3.3 low energy infralittoral rock1
Table 4 List of UK marine habitat features prioritised by UK devolved administrations for inclusion for designation within the national MPA network. Habitat features are cross referenced with comparable features listed in Annex I of the Habitats Directive and the OSPAR T&D as appropriate. 1 indicates the feature is included in the Habitats Directive Annex I list and 2 indicates the feature is included in the OSPAR List of Threatened and/or Declining Species and Habitats. Equivalent features for each of the three devolved administrations are in the same row of the table. MCZs (England & Wales)
MCZs (Northern Ireland)
NC MPAs (Scotland)
Habitat Features of Conservation Importance (FOCI) ✓ Blue Mussel Beds (inc. Intertidal Beds on Mixed and Sandy Sediments)12 ✓ Maerl Beds2 ✓ Horse Mussel (Modiolus modiolus) Beds12 ✓ Native Oyster (Ostrea edulis) Beds2 ✓ Seagrass beds2 ✓ Estuarine Rocky Habitats ✓ Fragile Sponge and Anthozoan Communities on Subtidal Rocky Habitats ✓ Cold-Water Coral Reefs2 ✓ Sea-Pen and Burrowing Megafauna Communities2 ✓ Deep-Sea Sponge Aggregations2 ✓ Coral Gardens2 ✓ File Shell Beds ✓ Intertidal Underboulder Communities ✓ Littoral Chalk Communities2 ✓ Peat and Clay Exposures ✓ Honeycomb Worm (Sabellaria alveolata) Reefs1 ✓ Ross Worm (Sabellaria spinulosa) Reefs12 ✓ Sheltered Muddy Gravels ✓ Subtidal Chalk ✓ Tide-Swept Channels x x
Priority Marine Features (PMF) Habitats ✓ Blue Mussel Beds (inc. Intertidal Beds on Mixed and Sandy Sediments)12 ✓ Maerl Beds2 ✓ Horse Mussel (Modiolus modiolus) Beds12 ✓ Ostrea edulis Beds2 ✓ Seagrass Beds2 ✓ Estuarine Rocky Habitats ✓ Fragile Sponge and Anthozoan Communities on Subtidal Rocky Habitats ✓ Cold-Water Coral Reefs2 ✓ Sea-Pen and Burrowing Megafauna Communities2 x x x x x x x x x x x ✓Mud Habitats in Deep Water ✓ Stable Sand with Associated Fauna
NC MPA Search Features ✓ Blue Mussel Beds12 ✓ Maerl Beds2 ✓ Horse Mussel Beds12 ✓ Native Oysters2 ✓ Seagrass Beds2 x x x x ✓ Deep-Sea Sponge Aggregations2 ✓ Coral Gardens2 x x x x x x x x x x x (continued on next page)
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Table 4 (continued ) MCZs (England & Wales)
MCZs (Northern Ireland)
NC MPAs (Scotland)
x x x x x x
x x x x x x
x x x x x x
x x x x x x
x
x
✓ Subtidal Sands and Gravels (Offshore) ✓ Carbonate Mound Communities ✓ Burrowed Mud ✓ Flame Shell Beds ✓ Inshore deep mud with burrowing urchins ✓ Kelp and Seaweed Communities on sublittoral Sediment ✓ Low or Variable Salinity Habitats ✓ Northern Sea Fan and Sponge Communities ✓ Offshore Deep Sea Muds ✓ Sea Loch Egg Wrack Beds ✓ Seamount Communities ✓ Shallow Tide-Swept Coarse Sands with Burrowing Bivalves ✓ Tide-Swept Algal Communities
Appendix A. Supplementary data Supplementary data to this article can be found online at https://doi.org/10.1016/j.marpol.2019.103717.
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