Demersal Fisheries Management Plans proposals: strategic environmental assessment - environmental report

3. Environmental Baseline

Summary of the Current State of the UK Marine Environment

Section 3 provides a summary of the current state of the UK marine environment for each of the environmental issues screened into this SEA, and where applicable their associated UK MS descriptors (Table 4). The SEA has been conducted against the environmental baseline set out in these sources of existing information. We acknowledge that there are some uncertainties and evidence gaps in the environmental baseline. However, we consider that this environmental baseline provides a comprehensive level of information to undertake an effective assessment and provide informed evidence-based recommendations. Where required, further detailed assessments using additional evidence will be completed ahead of the implementation of FMP measures.

It is likely that without the proposed FMPs, those issues which are contributing to the current state of the marine environment will likely continue to have an influence. The proposed FMPs seek to promote the management of the fisheries in a more coherent and coordinated manner that considers wider environmental issues. The FMPs therefore have the potential to improve the current state of the environment set out below, both where no improvement has been observed, and where positive trends have been identified. Section 6 and 7 considers how the implementation of the FMPs’ proposed policies and actions could change the baseline.

Biodiversity, Flora, Fauna and Geodiversity^[5] (Geology and sediments)^[6]

The primary source of information on the current state of the UK marine environment came from the UK MS descriptor status assessments, The updated UK Marine Strategy Part 1, published in 2019. The impact of fishing has been considered as part of the assessment on the UK MS descriptors, therefore information on the impact of fishing activity on the marine environment has been included in the sections below as part of the baseline. For further information on the baseline related to UK MS descriptors see Appendix B.

D1 and D4 – Cetaceans

Cetaceans (whales and dolphins) are an important marine ecosystem component that contributes to overall levels of biodiversity (D1). In addition, as top predators, the abundance of cetaceans can also provide some understanding on how the food web is functioning (D4).

The current status of cetaceans for both the North Sea and Celtic Sea is mixed. While there are some aspects that are in line with the achievement of GES, much of the picture is unclear. The impact of various net fisheries is leading to bycatch that, in places, might be impacting long term population viability of harbour porpoise.

Other than for a limited number of coastal bottlenose dolphin populations, it is unclear whether the abundance and range of most cetacean species can be considered in line with GES. Fisheries and the removal of prey species is one of several activities/pressures that have the potential to result in changes to cetacean abundance and distribution.

D1 and D4 – Seals

Seals are an important marine ecosystem component that contributes to overall levels of biodiversity (D1). In addition, as top predators, seal productivity can also provide some understanding and insight as to how the food web is functioning (D4).

Grey seal populations and productivity continues to increase, and targets are being met. Bycatch (largely in tangle/ trammel nets) is occurring but not at levels that threaten population viability. For harbour seals, the status is not in line with GES where population declines have occurred in some areas. The cause is unknown. It is not thought to be linked to bycatch as occurrences are rare and there is no indication that it is linked to other pressures associated with fishing.

D1 and D4 – Birds

Seabirds are well monitored species that are an important marine ecosystem component that contributes to overall biodiversity (D1). In addition, as top predators, the abundance of birds can also provide some understanding and insight as to how the wider food web is functioning (D4).

Seabird populations are currently below the level that is considered to meet GES and the situation is deteriorating. Some declines in breeding success have been linked to prey availability caused by climate change and/or past and present fisheries. Invasive predatory mammals are also known to impact breeding success on island colonies. The impact of bycatch will be included in future assessments and current evidence suggests that some longline and static net fisheries could be having possible population level impacts on certain species.

D1 and D4 – Fish and D3 – Commercially exploited fish and shellfish

Fish are an important ecosystem component that contributes to overall levels of biodiversity (D1). In addition, fish of different species have a significant role in marine food webs (D4), acting as both predators and prey. Some fish species are commercially exploited, and only a proportion of these have managed quotas. Over exploitation can lead to a decline in stocks (D3) which can reduce both future commercial opportunities and have wider ecological impacts.

The current status of fish communities in the UK is primarily shaped by historical over-exploitation by fisheries, while ongoing over-exploitation continues to be a notable contributing factor. Improved fisheries management since the 1990s has resulted in more stocks being fished at or below MSY levels, so although the target is not yet met there is a positive trend. Improved fisheries management has also resulted in some positive trends in fish communities beyond the targeted stocks.

D1 & D6 – Benthic Habitats

Benthic habitats are an important ecosystem component that contributes to overall levels of biodiversity (D1). It is also important to ensure the structure and function of benthic ecosystems is adequately safeguarded by considering seafloor integrity (D6).

There is widespread disturbance of seabed habitats by demersal towed gear and other marine activities, and this is preventing the achievement of GES. Other impacts from non-fisheries activities may also be having an influence, but to a much lesser degree.

D4 – Food webs

Food webs (D4) are the network of predator-prey relationships that occur in the marine environment, from phytoplankton to top predators such as birds or seals. Fish communities are a key component of food webs. Knowledge of food webs allows understanding of how changes at one trophic level can impact those above and below it.

Historic fishing activity which has contributed to the current environmental baseline has had a large impact on fish community structure which is a key component of marine food webs. With improved fisheries management focusing on stocks, some recovery is occurring. However, the management of fish stocks solely to safeguard future fisheries will not necessarily lead to all food web targets being met. Changes in plankton are likely driven by prevailing environmental conditions, but other impacts cannot be ruled out.

Water Quality

D10 – Marine Litter

Marine litter, including from fishing activities, is a significant pressure on marine ecosystems and water quality. The UK has not yet achieved its aim of GES for litter. Beach litter levels in the Celtic Seas have remained largely stable since the assessment in 2012, whilst beach litter levels in the Greater North Sea have slightly increased. Waste fishing material is a component of beach litter. Both floating litter and seafloor litter remain an issue, with plastic the predominant material. Achieving GES for marine litter requires improved waste management practices, the reduction of lost or discarded fishing gear and increased awareness and monitoring of the issue.

D11 – Underwater noise

Underwater noise from fisheries, while not the primary source, can still contribute to the overall noise pollution in the marine environment. Fishing vessels will contribute to underwater noise through sonar, engine noise, gear interacting with seabed and deploying and retrieving gear.

The achievement of GES for underwater noise in the UK is uncertain. Research and monitoring programmes established since 2012 have provided an improved understanding of the impacts of sound on marine ecosystems. However, achieving GES for underwater noise will require better understanding and monitoring of the issue, as well as the development and implementation of strategies to manage noise pollution from various sources.

Climatic factors

Climate change impacts are not part of the UK MS, therefore evidence from other sources was used to provide baseline information in relation to this issue. Statistics from the Department for Energy Security and Net Zero (DESNZ) (formally known as Department for Business, Energy & Industrial Strategy (BEIS)), Department for Transport (DFT) and Engelhard et al (2022) report on Carbon emissions in UK fisheries, were used to identify the contribution UK fishing fleets have to the total carbon emissions at sea each year.

Vessel Emissions

For 2019, estimated emissions by the UK fishing fleet (802 kt CO₂e) would have represented 0.18% of the UK’s total territorial emissions (455 Mt CO₂e) ^[7], or 0.66% of the UK’s domestic transport emissions (122 Mt CO₂e)^[8]. To put this into context, estimated emissions by the UK fishing fleet would have been equivalent to 1.7% of total agricultural emissions in 2019 (46.3 Mt CO₂e).

Recent analysis has shown that the total UK fishing fleet segment using demersal trawls and seines, which comprises of 402 vessels, produced approximately 30% (249kt CO₂e) of the total carbon emissions at sea each year across the UK’s fishing fleets. Drift and fixed net fisheries (237 vessels) produced approximately <2% (13kt CO₂e), and beam trawls (73 vessels) produced approximately 13% (107kt CO₂e). Whilst passive gears are generally less emission-intensive than mobile gears, quantification of carbon emissions across the fishing fleet supply chain (for example, preharvest through to postharvest) is required to truly understand the fisheries carbon footprint.

Blue Carbon

Photoautotrophic marine ecosystems, such as seagrasses and saltmarshes, are able to capture and store carbon and are known as blue carbon ecosystems Currently there is no comprehensive assessment of the impact of fishing using mobile demersal gear on organic carbon stocks. A new cross-Administration UK Blue Carbon Evidence Partnership has been formed to improve the evidence base on blue carbon habitats in UK waters, advancing our commitment to protecting and restoring blue carbon habitats as a nature-based solution. Through the partnership, announced at Conference of the Parties 26 (COP26), UK Administrations will work together to address key research questions related to blue carbon.

Climate change impacts on demersal stocks and fisheries

Climate change and warming oceans are changing the distribution and fish assemblages of commercially important species^[9]. Most species in the scope of the Demersal/Whitefish FMPs are expected to move northward in response to climate change with northwest European waters expected to be less suitable for key commercial species such as cod, haddock and saithe^[10]. As ocean temperatures rise, suitable spawning areas for most demersal species covered in the FMPs are expected to shift poleward to cooler waters.

Cultural Heritage

The definition of the ‘marine and aquatic environment’ in the Fisheries Act 2020 (section 52) includes features of ‘archaeological or historic interest in marine or coastal areas. These features should be regarded as part of the wider marine environment.

Cultural heritage impacts are not part of the UK MS, therefore evidence from other sources were used to provide baseline information in relation to this issue.

The Fishing and the Historic Environment report produced by Historic England was used as the primary source of information on the interactions between commercial fishing and the marine historic environment.

The report identifies that positive and negative interactions can arise when archaeological material present on the foreshore and seabed is encountered during commercial fishing.

The following interactions between fishing gear and marine heritage assets can occur^[11]:

• Interactions with drift nets and pelagic long lines have a low significance resulting from entanglement and snagging on marine heritage assets.
• Demersal trawl and dredge gears are widely used and are most likely to interact with marine heritage assets. Direct interactions with heavy bottom gears, are likely to be significant. However, some archaeological resources may not be discovered without interactions with fishing gear, and therefore significance of the interaction with findspots^[12] is moderate because of both positive and negative impacts.
• Interactions with demersal seine netting may have a low to moderate significance resulting from limited interaction with the seabed by the ropes used to haul the seine net.
• Interactions with static/passive demersal nets and long lines may have a low to moderate significance resulting from a higher likelihood of entanglement and snagging, and anchoring impacts.

The report identifies several potential and evidenced interactions between commercial fishing and marine heritage assets. However, given the anecdotal nature of many of these interactions, a comprehensive assessment of the extent of interactions and their impacts is currently not available for Scottish, English, Northern Irish and Welsh waters.

In Scotland Historic Marine Protected Areas (HMPAs) are marine historic assets of national importance which survive in Scottish territorial waters (out to 12 miles offshore) that are protected by law. There are currently 8 historic Marine Protected Areas in Scottish waters. Further information and datasets on Scotland’s Marine historic environment and cultural heritage can be found at Historic environment and cultural heritage | Scotland's Marine Assessment 2020.

The historic environment map viewer for Northern Ireland provides an overview of historic sites and landscapes Historic Environment Map Viewer | Department for Communities (communities-ni.gov.uk).

The Managing the Marine Historic Environment report produced by Cadw^[13] on behalf of the Welsh Government outlines the interactions between commercial fishing and the historic marine environment. The report explains the Welsh Government’s approach to managing the marine historic environment and offers best-practice guidance for its protection. The marine historic environment can be defined as places under the sea and in the intertidal where evidence for human activity is preserved.

Landscape and Seascape

There is no legal definition for seascape in the UK, but the European Landscape Convention (ELC) defines landscape as “an area, as perceived by people, whose character is the result of the action and interaction of natural and/or human factors” and includes land, inland water and marine areas. In the context of the Marine Policy Statement (MPS) a seascape has been set out to mean landscapes with views of the coast or seas, and coasts and the adjacent marine environment, (including the underwater environment), with cultural, historical and archaeological links with each other.

The ‘value’ of many of the UK’s seascapes is reflected in the range of designations which relate in whole or in part to the scenic character of a particular area, (e.g. Area of Outstanding Beauty (AONB), Heritage Coast, National Scenic Area), however the ELC and MPS (and most recently seascape assessments covering the English Marine Plan regions) define landscape and how they are to be considered in more general terms, acknowledging the value of all landscapes whether or not they are subject to designation^[14].

The seascape constitutes of a suite of different characteristics that include natural factors, cultural and social factors and cultural associations. Under these character headings exists a number of subheadings that include Geology, Seabed, Tides and Coastal processes (natural factors), Surface water features, Sunken and Buried Features and Use of Coast and Sea (cultural and social factors) Media, People and Writers (cultural associations)^[15].

Fishing and commercial fishing vessels are considered as seascape features and activities. Fishing ports and related fishing infrastructure are considered as landscape features^[16]. Fishing therefore is an important component of the overall landscape and seascape character.

Fishing activity using demersal towed gear has been identified as causing damage to submerged peaty deposits known as moorlog^[17]. However, a comprehensive assessment of the extent of interactions and their impacts is currently not available. Conserving moorlog as potential blue carbon habitats might contribute to climate change mitigation and adaptation.

Existing Environmental Effects of Demersal Fishing

The draft Whitefish/Demersal FMPs focus on achieving the sustainable harvesting of stocks. This focus seeks to reduce the environmental risks linked to over-fishing these stocks, thereby giving positive benefit to environmental status.

Nevertheless, fishing within sustainable limits for the target stocks (MSY or appropriate proxies) may reduce but will not eliminate some of the negative impacts of that fishing activity on the wider marine environment. These impacts are identified in the sections below.

As described in Section 2, this Environmental Report focuses on assessing how the policies and actions in the draft Whitefish/Demersal FMPs are likely to give rise to both significant positive and negative environmental effects. More detailed fisheries assessments which consider current activity are already in progress or have been completed. These assessments may be used to inform the FMPs’ actions as they are delivered, and include:

• UK Marine Strategy assessments of the status of the wider marine environment
• The Marine Directorate’s ongoing PMF and MPA fisheries assessments programmes.
• Defra’s Revised Approach to fisheries management programme (inside six nautical miles) in England.
• The Marine Management Organisation’s (MMO) ongoing Fishery Assessment programme (outside six nautical miles) in England.
• Commercial fishing is a key activity policy in the draft Marine Plan for Northern Ireland.
• The Assessing Welsh Fishing Activities Programme is in place in Wales. This work assesses likely impacts to habitats and features from specific gears - it does not assess impacts from current activity, but the generic assessments are used to inform management.

Nevertheless, this ER acknowledges the likely significant effects associated with fishing activity being managed through the Whitefish/Demersal FMPs and sets out in broad terms how the FMPs will seek to avoid, reduce, or at least mitigate significant negative effects. Biodiversity, Flora, Fauna and Geodiversity, and Water quality.

Environmental Effects Associated with MPAs

Advice provided to fisheries policy authorities by Statutory Nature conservation Bodies (SNCBs) gives more detail on the risks associated with fishing for species covered by the Whitefish/Demersal FMPs in relation to the designated features of MPAs, UK Marine Strategy Descriptors (UK MS) and priority marine features (PMFs) for Scotland. Joint advice from Natural England and JNCC, commissioned by Defra and covering English waters, was received for the North Sea Whiting FMP, Northern Shelf Haddock FMP, North Sea and West of Scotland Saithe FMP, North Sea and West of Scotland Monk/Angler FMP, and Northern Shelf Cod FMP. Joint advice from JNCC and NatureScot, commissioned by the Scottish Government's Marine Directorate and covering Scottish waters, was received for all Whitefish/Demersal FMPs in Scottish waters as part of a single assessment.

Inside the boundaries of Scottish MPAs, the Marine Directorate assess human activities that could interact with the designated features of MPAs, seek the advice of SNCBs and introduce management where required. Stakeholders have worked closely with regulators to help develop measures to mitigate impacts within inshore and offshore MPAs. Therefore, appropriate management should either be in place or introduced soon to ensure any fishing within MPAs is compatible with the MPA’s conservation objectives. Current management measures already in place related to the use of bottom towed gear is detailed at MPA monitoring strategy - Marine environment.

In England the assessments of the impact of fishing activities inside MPAs are undertaken by the IFCAs within 6nm and the MMO outside 6nm. Stakeholders have worked/will work closely with regulators to help develop measures to mitigate impacts within inshore and offshore MPAs. Appropriate management is or will be in place to ensure any fishing within MPAs is compatible with the MPA’s conservation objectives. Current management measures already in place are detailed on the MMO and Association of IFCAs websites.

There was no formal conservation advice specifically for Welsh waters at the point of developing this SEA, however the understanding is that, the ER was developed following Natural Resources Wales (NRW) engagement in the scoping exercise and their advice was considered and reflected in this report. NRW were asked by Welsh Government to produce high-level risk based advice on the impacts of fishing activities to support the development of other relevant mixed demersal fisheries FMPs. Welsh Government are satisfied that the advice provided in that assessment has parallels to the 11 UK Whitefish/Demersal FMPs.

As stated elsewhere in this report, it should be noted that there is no targeted fishery for hake in Wales. Hake is occasionally caught as bycatch as part of demersal mixed fisheries which are covered by other forthcoming FMPs.

In Northern Ireland, current fisheries management measures exist for nine inshore MPAs through The Marine Protected Areas (Prohibited Methods of Fishing) (Amendment) Regulations (Northern Ireland) 2022. Further fisheries measures are being drafted for three offshore MPAs (South Rigg MCZ, Queenie Corner MCZ and Pisces Reef SAC) and will be consulted on later this year.

Whilst existing MPA site management considers fishing activity that occurs within the site’s boundaries, there remains the potential for fishing activity outside MPAs to have impacts on the features protected within the MPA. These impacts can occur when either the pressure exerted by the fishery impacts protected features beyond the spatial footprint of a particular fishing activity, (such as noise), or when the feature of an MPA is mobile and travels outside the site.

Environmental effects associated with designated features of MPAs in Scottish waters

The key risks of fisheries contained within the Demersal/Whitefish FMPs relating to the designated features of MPAs in Scottish and English Waters are summarised below.

Fisheries contained in the Demersal FMPs have the potential to impact the designated features of MPAs in three primary ways:

(i) through the bycatch and entanglement of designated features of MPAs

(ii) the direct (targeted) and indirect (bycatch) removal of prey species on which designated species depend, and

(iii) physical impacts to seafloor resulting in alterations to habitat feature or supporting habitat condition.

While the risk to the conservation status of mobile species that are designated features of MPAs through bycatch from mobile demersal gear is generally considered low, given the scale of these fisheries and significant gaps in the available evidence, the risk rating for bycatch in mobile demersal gears is considered moderate. Certain fish species such as the basking shark and flapper skate, several deep-water fish and elasmobranchs, may be at greater risk owing to their life histories. Gathering additional evidence has the potential to improve our understanding of risk and is essential for directing management in relation to these more sensitive species.

Static nets and longlines, primarily associated with the hake and anglerfish fisheries, present a considerable bycatch risk for birds and other mobile species which are designated features of MPAs in Scottish waters. Bycatch in static nets is considered the greatest threat to harbour porpoise, and the primary source of bycatch mortality among seals. Gillnet fisheries pose a significant bycatch risk to diving seabirds such as common guillemots, razorbills, and European shags. There are also concerns about the seabird bycatch in the Scottish and UK offshore longline fisheries, with fulmars being particularly vulnerable to bycatch in this gear type. Based on current evidence, the risk rating for bycatch in static nets and longlines is considered high, with more data collection required to understand the scale of the problem and improve the ability to assess risk. Again, this risk may be downgraded in future as the evidence base develops.

Juvenile gadoids are an important component of the diet for a variety of marine predators and are thus considered a key forage fish species. Forage fish are essential to marine food webs, often serving as the primary food source for higher trophic levels, including marine mammals and seabirds. Harbour porpoise, for example, are known to predate heavily on juvenile gadoids. Given the breadth and scale of fisheries included in the Demersal FMPs, it is likely, either through targeted fishing, bycatch or downstream impacts on spawning and recruitment, that there will be a reduction in the availability of juvenile gadoids and other prey species to marine predators designated within the Scottish MPA network. Recognising a potential impact pathway but lacking sufficient evidence to provide a confident conclusion, the risk of prey depletion to designated features of MPAs from demersal fisheries is considered moderate. Certain fisheries are likely to present a great risk than others, but further work is needed to help disentangle these risks.

Risks relating to the designated features of MPAs in English waters

• There is a high risk to conservation status of designated mobile species (birds and mammals) from static nets.
• There is a high risk to the conservation status of seabirds from longlines.
• While the risk to the conservation status of designated mobile species from demersal trawls is generally considered low, there are still significant gaps in the available evidence. As a result, the risk rating has been upgraded to moderate, taking a precautionary approach into account. Gathering additional evidence has the potential to downgrade this risk in the future.
• There is a moderate risk to designated mobile species (harbour porpoise) from reductions in the availability of juvenile cod and whiting as prey.

Environmental effects associated with UK MS Descriptors (Scottish waters)

Advice provided to fisheries policy authorities by the SNCBs gives more detail on the key risks to UK MS descriptors arising from cod, whiting, haddock, saithe, hake, monk, megrim and ling fishing and their likely impact on achieving Good Environmental Status (GES) (Appendix A). The following potential issues and their associated risk level^[18] have been identified for cod, whiting, haddock, saithe, hake, monk, megrim and ling fishing on UK MS descriptors:

There is a moderate risk to achieving GES for the biological biodiversity of seals, due to impacts from demersal fishing activities. Although bycatch in static nets is a significant source of mortality for seals, and demersal fisheries may reduce the availability of prey, at their current scales these pressures are not thought to be among the primary drivers for change with respect to achieving GES for seals. However, there are still significant gaps in the available evidence and research is ongoing to understand the drivers of seal population dynamics in Scotland and the UK. As a result, the FMP risk rating is assessed as moderate. Continued monitoring and enhanced data collection and research to address knowledge gaps may allow for a reassessment of this risk in future.

There is a high risk to achieving GES for the biological biodiversity of cetaceans and birds, due to impacts from demersal fishing activities. This rating is primarily driven by risk of bycatch in static net and longline fisheries for cetaceans and birds, respectively. Continued monitoring and enhanced data collection and research to address knowledge gaps may allow for a reassessment or improve the geographical specificity of this risk rating in the future.

There is a high risk to seafloor integrity due to benthic disturbance caused by mobile demersal fishing activities. However, due to data availability, this risk is assessed only based on data collated across the >12m UK mobile demersal fishing fleet. It does not include impacts from static gears; while these are likely to be lower risk, these gears have the potential to significantly impact seafloor integrity if operating at a high intensity. Further work is needed to disentangle and quantify impacts from individual fisheries covered by this generic advice.

There is a moderate risk of impacts from marine litter. More robust estimates of abandoned, lost, or discarded fishing gear in the fishery are required.

Risks relating to UK Marine Strategy descriptors (English waters)

Previous work by Natural England investigating the impact of the pressures associated with the fishing industry across all 11 descriptors of Good Environmental Status (GES)^[19] in the UK marine environment has highlighted 6 key issues^[20]. Of these issues, only a subset will be relevant to any particular fishery / sector.

The main interactions between the Whitefish/Demersal FMPs and UK MS Descriptors that have been identified are summarised below. The high-level assessments flag the potential risk based on the predominant gear types used across a range of fisheries.

• There is a high risk to achieving GES for cetaceans (D1 & D4) due to bycatch in static nets.
• There is a high risk to seabirds (D1 & D4) from longlines.
• There is a high risk to achieving GES for seafloor integrity (D1 & D6) due to benthic disturbance caused by demersal trawls and the contribution to current failure to meet targets. Strategic work at a broad geographic scale is required to identify opportunities to mitigate risk and understand trade-offs.
• There is a moderate risk to achieving GES for seals and seabirds (D1 & D4) due to bycatch in static nets.
• While the risk from demersal trawls and seines to achieving GES for marine mammals and seabirds (D1 & D4) is generally considered low, there are still significant gaps in the available evidence. As a result, the FMP risk rating has been upgraded to moderate, taking a precautionary approach into account. Gathering additional evidence has the potential to downgrade this risk in the future.
• There is a moderate risk to achieving GES for marine litter (D10) due to abandoned, lost or discarded fishing gear.
• There is a moderate risk to cetaceans (harbour porpoise, D1 & D4) through reduction in the availability of juvenile cod and whiting as prey.

Environmental effects associated with Scottish Priority Marine Features

Scottish Priority Marine Features Priority Marine Features (PMFs) in Scotland represent a selection of habitats and species identified for their conservation importance. These 81 features are acknowledged for their national significance and the role they play in supporting marine biodiversity. The purpose behind identifying PMFs is to focus conservation efforts, guide management actions, and ensure the protection and enhancement of marine biodiversity within Scottish waters. Scotland National Marine Plan policy GEN 9 states that development and use of the marine environment must not result in significant impact on the national status of PMFs.

In addition to the bycatch risks outlined for MPA designated species above, mobile demersal gears covered by the Demersal FMPs present a further bycatch risk for all listed fish species, including several long-lived species with an increased vulnerability to bycatch mortality. For listed fish which are also commercial stocks, risks of bycatch may be mitigated through their own stock management processes, but significant gaps in the available evidence remain. Risks for PMF marine mammals are likely to echo the risks outlined above for MPA features. The risk rating for bycatch in mobile demersal gears is considered moderate. Gathering further evidence has the potential to downgrade this risk in future.

Risks relating to longlines are downgraded from the MPA feature assessment above as the PMF list does not include birds, which are the most vulnerable group in terms of bycatch in this gear. However, there is bycatch of potentially vulnerable long-lived fish within this fishery, thus a moderate risk rating is proposed for bycatch of PMFs in longlines.

The potential impact of static nets echo those proposed above for MPA features, as such the risk rating for bycatch of PMFs in static nets is considered high.

Owing to a potential impact pathway but lacking sufficient evidence to provide a confident conclusion, the risk of prey depletion to PMFs from demersal fisheries is considered moderate.

As the benthic species and habitat PMFs are also represented across the Scottish MPA network, it is assumed that these features will be offered some protection through the MPA management process. Therefore, some of these impacts on national status of PMFs will be mitigated, and the risk rating for physical impacts to benthic and habitat PMFs from mobile demersal gears is considered moderate. Physical impacts from static demersal gears are likely to represent a lower risk to benthos but there may be areas where high intensity static fishing can have a moderate impact on PMF habitats and benthic features through physical disturbance.

Climatic Factors

Vessels fishing for cod, whiting, haddock, saithe, hake, monk, megrim and ling contribute to the total carbon emissions at sea each year by the UK’s fishing fleets. While the estimated emissions by the UK fishing fleet represents a small proportion of overall emissions in the UK, decarbonising the fleet and moving towards net zero will help reduce the contribution of fisheries activities to climate change.

No conclusive evidence is currently available on the impact of fishing activity for demersal species on organic carbon stocks. However, the impact of towed demersal gear on blue carbon is of concern. Improved recording of the intensity of fishing using this gear on the seabed more broadly will help any future assessment of any effects on organic carbon stocks when the evidence base on blue carbon habitats in UK waters improves.

Cultural Heritage

Fishing activity can have both positive and negative effects on marine heritage assets. The positive effects relate to the discovery of marine heritage assets during fishing activity, with both past and future discoveries of findspots often reliant on fishing gear interactions. Negative effects can be caused by physical disturbance to cultural heritage on and within the seabed. Specific effects include: impeded access and interpretation of assets by fishing gear (e.g. nets, lines and ropes) collecting around physical structures; direct damage of assets by gear, usually towed gear, causing irreparable alteration to physical structures; burial of archaeological material by sediment during fishing practices; removal of the archaeological material from the seabed during fishing practices; and transferal of archaeological material from its original place on the seabed during fishing practices. Avoiding negative interactions with marine heritage assets will help to conserve them for their enjoyment by future generations.

Benthic towed gear has been identified to cause damage to marine heritage assets. Historic England have evidence of two recent examples of damage from fishing activity to designated heritage assets, the Klein Hollandia (aka Eastbourne Wreck, LEN 1464317) and the Rooswijk (LEN 1000085).

The marine historic environment also plays an important role in providing ecosystem services in relation to nature conservation, sea angling, recreational diving and commercial fishing. Marine heritage assets, particularly ship and plane wrecks, can provide habitats for marine life, with fish often aggregating around them for refuge or to feed. Avoiding negative interactions with marine heritage assets that act as habitats can positively contribute to the conservation of the wider marine environment.

Landscape and Seascape

Fishing activity above the surface is considered a feature of the marine seascape, therefore the presence of trawling vessels is not considered to have a negative effect on this aspect of the seascape character.

Fishing activity using demersal towed gear has the potential to cause physical disturbance of the seabed, and therefore could impact deposits associated with prehistoric landscapes that are now submerged by sea-level rise. These former landscapes, referred to as moorlog, are often represented by peaty and other fine-grained deposits. Examples of these prehistoric landscapes and deposits can be found in the Dogger Bank region^[21].

The impact of demersal towed gear on the seabed is also considered as part of the GES Descriptor D6 – Seabed Integrity.