Appendix 3 – Research and knowledge gaps

Despite the wealth of knowledge which exists about the Solway there are still many gaps in knowledge and information. This is due to a variety of reasons including gaps in monitoring, collection, technological limitations, unknown variables of the marine environment, and the fact that the future is unknown, and changeable depending on actions and impacts. There are also many unknowns about the marine environment.

There may be research or projects ongoing or created in relation to these data gaps and nothing within this section is intended to undermine or question new, ongoing or past research, data or information. In a constantly evolving knowledge base there will be ongoing changes to the knowledge gaps which currently exist for the marine environment.

Solway specific data can be scattered and limited at times, covering parts of the coastline, one side of the Firth but not the other, or are project specific. The different spatial scales, and locations of data and information is not necessarily a data gap, despite some data being consistent across boundaries, but can be a barrier to forming a full picture of the Solway Firth ecosystem.

There is limited regional specific data for many sections within the Solway Review, for example, dissolved oxygen, and spatially and temporally limited data for salinity. Within Scotland’s Marine Assessment, many of the topics lacking regionally specific data are identified. Furthermore, some of the assessments within Scotland’s Marine Assessment have been conducted at the scale of the four Scottish biogeographic regions. The Solway forms part of a biogeographic region called the ‘Irish Sea’ along with the Clyde. Although this allows conclusions to be drawn and topics assessed, the results may be less representative of the rural, shallow Solway which is a very different marine region to the neighbouring busy and industrialised Clyde region. The biogeographic data reported from monitoring stations, is more often from the Clyde rather than the Solway, sometimes significantly more. For example, out of the 9 monitoring stations used to assess the status and trend for PAH/PYR1OGEQ concentrations in shellfish in the ‘Irish Sea’, 8 of these stations were located in the Clyde and only 1 in the Solway. The Marine Assessment does at times differentiate within the biogeographic region if one marine region has more concerns etc. For example, the ‘external fish disease’ assessment status for the Irish Sea (Clyde and Solway) biogeographic region outlines ‘many local concerns, particularly in the Clyde, with some sites exceeding the OSPAR Environmental Assessment Criteria/OSPAR Environmental Assessment Criteria-proxy’ (Moffat et al, 2020).

All sections within the Solway Review will have data gaps, often linked to this lack of regional specific data or data which is Scotland/England specific in nature. Without region specific data it is difficult to draw confident conclusions about the state or trend of certain topics in the Solway Firth. The lack of regionally specific and Solway-wide specific data should be considered as a data gap throughout.

The unprecedented situation arising from the COVID-19 pandemic has impacted every aspect of the UK including the Solway Firth, and there will be socio-economic changes going forward which need to be assessed in the future. The increase in UK coastal tourism and other socio-economic changes will continue and impacts on the local economy and environment must be considered and monitored. The ongoing changes, and long-term impacts of the pandemic remain unknown at present. Similarly, the UK leaving the EU will likely bring about changes in how the UK manages and monitors the marine environment. These changes are an outstanding data gap.

The socio-economic Productive chapter of the Solway Review has data gaps due to the manner in which data is collected and made available. As outlined in the main Productive page, it is important to note that there are a number of challenges when gathering and analysing data at the regional level.

These can be categorised as:

  • Availability of data– there are numerous sources of rich economic, sectoral and wider data that can be utilised within the assessment. However, these data sources are all subject to discrepancies with regards to publication, in particular, the frequency of publication (monthly/quarterly/annually, and by time of year), geographic disaggregation, and data suppression. Where data allows, the format and reporting against the individual sectors is consistent throughout.
  • Data Suppression – publicly available data that could potentially identify individuals or businesses cannot be disclosed due to commercial confidentiality – this is a challenge in rural areas, and where there are a limited number of large employers operating in the area. Therefore, at lower geographic and sectoral levels, there will often be data that is not disclosed. Please note that when analysing trend data, supressed data is included to calculate the overall change.

There are also challenges with measuring the economic activity generated by the sport, recreation and tourism sector as it encompasses a broad definition that cuts across many industry sectors. It is even more challenging to separate strictly marine tourism from terrestrial tourism. It can be difficult to capture the true contribution of this sector to the Solway as many recreational activities are free, but have associated benefits to the local economy such as to local businesses through food and drink etc. Close attention should be paid to ongoing changes to this sector especially in light of the socio-economic impact of COVID-19 on ‘staycation’ and local tourism around the UK.

What the Solway lacks in hard data can be partially made up for with the wealth of local knowledge of the Solway Firth. Locals around the Firth make a point of knowing about the features, species, and nature of the estuary and are very aware of changes in the environment. Many know stories of changes, and progressions over the course of their lives, and in some cases parents and grandparents’ lives are told through stories and oral history.

The following assessment of knowledge gaps as provided by Scotland’s Marine Assessment and additional Solway specific information or gaps identified. Note that in the knowledge gaps tables below all text is either directly from or heavily reliant on Moffat et al (2020) unless in orange.


Image; Dunskey Castle. © E. Baruah

Appendix 3 – Research and knowledge gaps

Knowledge Gaps - Physical characteristics and ocean acidification


Scotland’s Marine Assessment 2020 Knowledge Gaps (text from Moffat et al, 2020 unless in orange)
Topic & Theme Sub-theme (if there is one) Assessment Identified Knowledge Gap Solway – gaps and notes 
Physical characteristics and ocean acidification Circulation The general circulation in Scottish waters is well understood. The main evidence gaps are sustained and high-resolution direct observations of currents in Scottish waters, particularly the exchange in the northern North Sea. There are new data products (e.g. from remote sensing and numerical models) and new (e.g. autonomous) technologies under development which could fill this data gap.

The Overturning circulation in the Subpolar North Atlantic (OSNAP) programme is expanding the knowledge of the Atlantic Meridional Overturning Circulation and therefore the variability of Atlantic water in the Rockall, Bailey and Hatton regions, but more work is needed on the drivers of circulation variability, particularly in light of climate change.

Dissolved oxygen The relationship between biological and physical processes near the seafloor is poorly understood. Robust assessments of oxygen deficiency require improved availability of near-bed data on dissolved oxygen (DO) concentrations together with salinity, depth and temperature measurements.

Data on seabed DO are only collected consistently within a subset of the regions. At the Scottish Marine Region scale, this presents a number of data gaps. In addition, Water Framework Directive classification is based on monitoring in representative locations meaning DO is not routinely monitored in all water bodies. It is hoped that autonomous monitoring methodologies will provide more data in the future to improve our understanding seabed DO.

To better understand trends in dissolved oxygen in relation to climate change more data are required than those which are currently available. There may, therefore, be a requirement to expand the monitoring network to all regions to ensure long-term changes are captured.

There is limited dissolved oxygen data available in the Solway region and this has been acknowledged as a knowledge gap in the current assessment of overall Eutrophication status.
Ocean Acidification The Scottish ocean acidification dataset consists of 5 years of measurements at Stonehaven, north-east Scotland. This is insufficient to calculate accurate trends in overall pH. The data are consistent with both UK and global data for coastal/shelf sea areas with the carbonate system having a strong seasonal cycle linked to biological activity.

There are very few sustained carbonate chemistry monitoring data from Scottish waters, and those that are available have been collected over a very short timescale, < 20 years. To differentiate natural seasonal and inter-annual variation from anthropogenic driven impacts, data would be required over a multi-decadal timescale.

There are currently no assessment criteria in place for the status assessment of carbonate chemistry parameters and no indicator or potential indicator species groups recommended for monitoring ecosystem response to ocean acidification. These will require development for future assessments.

Salinity Salinity observations are generally sparse in both space and time, particularly compared to temperature. This affects the confidence that can be associated with determining long-term trends and spatial variability. Data gaps in Scottish waters are particularly focused on the west coast regions and most coastal areas. These gaps can be filled by initiatives such as the profiling float programme (Argo), using under-way measurement systems on ferries and voluntary observing systems, and by integrating computer simulations and new measurement techniques from autonomous technologies and remote sensing.
Sea level and Tides None provided
Stratification / potential energy anomaly In situ observations of vertical water column structure are relatively sparse and insufficient to quantify changes in stratification with time. Improved computer simulations of ocean processes would enable the application of numerical data products to assess changes in stratification.
Turbidity Three main knowledge gaps have been identified:

  • lack of ground-truthing of data in Scottish waters for ocean colour algorithm;
  • lack of data for offshore marine regions, particularly in the winter months;
  • restricted spatial extent of current data set

More work on remote sensing of suspended matter in Scottish waters is needed to improve confidence in these data, and allow for the analysis of trends.

Large gaps in knowledge exist due to limitations of ocean colour satellite data.

No trend assessment has been included due to insufficient data and the need for more in situ observations to validate the satellite data. Ocean colour measurements and algorithms are continuously improving, but often rely on detailed measurements of water optical properties and suspended sediment concentration.

Temperature Sea Surface Temperatures are observed well by both in situ and remote sensing observations. However, sub-surface temperature observations (near the sea bed or vertical water column profiles) remain relatively sparse. Sustaining observations at a regional level will be important to help identify how the regional temperature variability is influenced by global climate change.

Understanding of the variability at all timescales (seasonal, inter-annual, decadal and long-term) is based on observations from very long measurement records (longer than 30 years). Interruptions in these data (missing locations or broken in time) make the analyses of variability more difficult. These gaps may be improved by incorporating a combination of observations and numerical models (reanalyses).

Wave Climate There are not many observations of waves around Scottish coasts. Numerical models can fill in this missing information, but these do require observations for validation and reliable information on forcing mechanisms (such as meteorology and bathymetry). The inshore waters around Scotland, such as the west coast sea lochs, are not always well resolved by wave models, including the one used in this analysis. More information on wave climate in coastal regions should be collected.

Appendix 3 – Research and knowledge gaps

Knowledge Gaps - Clean and Safe - Eutrophication

The status for the Solway was assessed as ‘Few or no concerns’ overall for Eutrophication including all 4 of the assessments (Chlorypyll, dissolved oxygen, nutrient input, winter nutrient concentrations). The status had a medium confidence due to limited regional specific dissolved oxygen data available.


Scotland’s Marine Assessment 2020 Knowledge Gaps (text either directly from or heavily reliant on Moffat et al, 2020 unless in orange)
Topic & Theme Sub-theme (if there is one) Assessment Identified Knowledge Gap Solway – gaps and notes 
Clean and Safe


  Chlorophyll concentration No continuous dataset (from 1990 to 2018) exists for any of the Scottish Marine Regions (SMRs) in this assessment and the sampling effort is uneven across available data, both spatially and temporally. Datasets contain both chlorophyll-a concentrations corrected for and uncorrected for pheophytin-a, as agreed reporting of chlorophyll-a data has changed (OSPAR, 2012).

Where extensive sampling cannot be justified on a risk basis (such as offshore areas), effort should be made to integrate other sampling options, such as satellite and proxy measures of chlorophyll-a.



Trend analysis was carried out to determine if concentrations were increasing or decreasing.

Data were insufficient to attempt to detect a trend for the Solway


  Dissolved Oxygen Same as Physical characteristics and ocean acidification – Dissolved Oxygen (above) Limited regional specific dissolved oxygen data available
  Nutrient inputs into water  The dataset used in the assessment was developed following the OSPAR Riverine Inputs and Direct Discharges Monitoring Programme (RID), principles for regional OSPAR assessments. When aggregated to the scales required by the SMR assessment there were gaps in certain regions, particularly for riverine data. A methodology for determining atmospheric nutrient inputs at the SMR scale needs to be developed so that all inputs of nutrients can be assessed. There is no status assessment for nutrient inputs into the marine environment as there are no regionally set assessment thresholds.
  Winter nutrient concentrations Winter nutrient monitoring on the annual Clean Seas Environment Monitoring Programme (CSEMP) cruise is well established but does not include collection from all Scottish Marine Regions (SMRs). There are limited winter nutrient monitoring data available for the Clyde, Solway, Outer Hebrides and Shetland Islands (in more recent years). This is because the design of the sampling is around the contaminants and effects monitoring in sediment and fish with opportunistic collection of water for nutrients.

Annual means and percentile 95% confidence intervals were estimated for the relevant parts of 11 SMRs if the coverage of modelled values was regarded as satisfactory. Mean values were only estimated for an SMR when the predicted values covered at least 80% of the relevant area.  For example mean values for only 2009, 2016 & 2017 are presented for the Solway because the predicted values in other years covered <  80% of the Solway SMR  because of sampling.


Appendix 3 – Research and knowledge gaps

Knowledge gaps - Clean and Safe - Hazardous substances and their effects

The Solway was included in a status and trend assessment for the biogeographic Irish Sea region with the Clyde for all ‘Hazardous substances and their effects’ assessments, if there was a status and trend assessment undertaken (not all assessments conducted a status and trend assessment) apart from Radionuclides and Inputs of mercury (Hg), cadmium (Cd) and lead (Pb) in water. Overall the status and trends for Hazardous substances and their effects were; few or no concerns as a whole, but many local concerns, particularly in the Clyde, with some sites exceeding the EAC/EAC-proxy. Two stars for confidence in the status is due to lack of suitable assessment criteria for some determinands (metals in biota and some biological effects measurements)



Scotland’s Marine Assessment 2020 Knowledge Gaps (text either directly from or heavily reliant on Moffat et al, 2020 unless in orange)
Topic & Theme Sub-theme (if there is one) Assessment Identified Knowledge Gap Solway – gaps and notes 
Clean and Safe

Hazardous substances and their effects


Biological Effects of contaminants EROD- an indicator of exposure of fish to some organic contaminants There is a lack of data to make a regional assessment for all Scottish biogeographic regions. To improve this, further fish sampling sites are required in the Minches and Western Scotland to give sufficient numbers of stations with good geographic spread.

For other indicators Environmental Assessment Criteria (EAC) are used to assess environmental harm. An EAC has not been developed by OSPAR for EROD as suppression of EROD activity has been reported at high concentrations of some contaminants.

There were insufficient data for the assessment of Scottish Marine Regions.

Additional sampling and analysis would be required if regional assessments were to be made for all Scottish Marine Regions. Marine Scotland Science is currently investigating this, however, EROD activity is only measured in fish and assessment criteria have only been developed for certain species, there may not be suitable species in all SMRs. Furthermore, due to the quantity of fish required for a reliable assessment where a minimum of 3 sites is essential, collecting this many fish from each SMR may not be possible.

The Clean Seas Environment Monitoring Programme (CSEMP) sampling design was based around the biogeographic regions therefore there are insufficient data for status and trend assessments of all SMRs. Each SMR will be within a biogeographic region, however in most SMRs there will be no or few stations.

Trends in EROD activity were assessed in Scottish biogeographic regions where there were at least five years of data from representative sites. There were sufficient data for trend analysis in the Northern North Sea and the Irish Sea (Clyde and Solway). Only one of these stations was located in the Solway, the other four were in the Clyde.

A number of the sites sampled in the Irish Sea (Clyde and Solway) are around the Clyde, an area with a high level of industry, which has resulted in high concentration of contaminants. The high level of EROD observed here is consistent with other contaminant assessments, e.g. PAHs and PCBs. Trend analysis showed that EROD activity levels were stable. However, two sites in the Clyde, Holy Loch and Garroch Head, are considered ‘impacted’ (those close to a point source) stations and therefore removed for the regional trend assessment.

External fish disease There are a lack of data available in some Scottish biogeographic regions. To improve this, further monitoring stations are required in the Irish Sea (Clyde and Solway), Minches and Western Scotland, and Scottish Continental Shelf. Since there are only assessment criteria available for common dab, this further limits the available data, especially in areas like the Irish Sea (Clyde and Solway) where there are sufficient fishing sites for most other contaminant assessments. However, a different species of fish is currently sampled from these locations making them unsuitable for inclusion in the fish disease assessment.

Further work into the links between Fish Disease Index and contaminant exposure would be useful as this assessment of fish health has contrasting conclusions to the other contaminant assessments. Inclusion of emerging contaminants would also be helpful as only a limited number of contaminants are monitored.

Imposex in Dog whelks There are a lack of data available in some biogeographic regions. This is due to a reduction in the survey as the level of imposex was declining. To make a regional assessment to confirm this, further monitoring stations are required in the Irish Sea (Clyde and Solway), Minches and Western Scotland and Scottish Continental Shelf. There are insufficient data for a regional assessment for all SMRs.

There are no OSPAR assessment criteria for Tri-Butyl-Tin (TBT) concentrations in sediment. The Environmental Quality Standard (EQS) proposed by Sweden is being trialled in OSPAR assessments, however these are not agreed yet.

The imposex assessment methodology does not take into account sites that have been visited, but where there were no animals present, for example, sites that historically have had dog whelk populations that have declined to a level of local extinction due to TBT exposure. Often sites have recovered, but this is not always the case. Unfortunately, if no dog whelks are present at a site it cannot be certain that TBT concentrations remain the reason the site has not been repopulated. Therefore, these sites are excluded from the regional analysis.

Imposex in dogwhelks was assessed in biogeographical regions, meaning the Solway was in a regional assessment with the Clyde. Unlike with many other assessments, all three monitoring stations were in the Solway (two Loch Ryan sites and one in Wigtown Bay).


For regional assessment and trend analysis, only biogeographic regions with a minimum of three suitable stations with a reasonable geographic spread were included. There were insufficient data for regional analysis of the Irish Sea (Clyde and Solway)

Contaminants in sediment and biota Concentration of mercury (Hg), cadmium (Cd) and lead (Pb) in biota and sediment


There are a lack of monitoring data, particularly for sediment in the Scottish Continental Shelf. This is partly due to difficulties sampling in this area and the sediment type which is mainly sandy or rock and therefore not suitable for contaminant monitoring.

There are no OSPAR Environmental Assessment Criteria (EAC) available for heavy metals in biota, therefore the European Commission Food Limit was used as an EAC-proxy. There is no clear evidence to link these limits to environmental harm in sea life. The confidence in assessment for trace metals in biota is low. There is a need to develop EACs for metals in biota.

There were insufficient data for the assessment of all SMRs. Additional sampling and analysis would be required if regional assessments were to be made for all SMRs. However the sediment type may not be suitable for contaminant analysis in all SMRs. In addition, shellfish sampling in all SMRs might not be possible, due to the lack of mussels in some areas. It may be possible to use heavy metal data for scallops to improve the spatial coverage for regional assessments, Marine Scotland Science (MSS) is currently investigating this.

Similarly, this assessment was conducted on biogeographical scale, with the Solway and Clyde as the Irish Sea region. There were more monitoring stations used to assess heavy metal concentrations in sediment and biota (particularly biota monitoring stations) in the Clyde than the Solway, therefore may not accurately represent the Solway. 
Concentration of Polycyclic aromatic hydrocarbons (PAHs) in biota and sediment


There were a lack of monitoring data, particularly for sediment in the Scottish Continental Shelf. This is partly due to difficulties sampling in this area and the sediment type which is mainly sandy or rock and therefore not suitable for contaminant monitoring.

The United States Environmental Protection Agency’s Effects Range-Low (ER-L) was used in the assessment of PAHs in sediment, as there are no OSPAR EACs currently available. There is a need for EACs to be developed for both alkylated and parent PAH in sediment. More research may be needed to identify the specific sources of PAHs that are resulting in concentrations being above OSPAR Background Assessment Concentration (BAC) and not decreasing in sediment in some areas.

There were insufficient data for the assessment of all SMRs. Additional sampling and analysis would be required if regional assessments were to be made for all SMRs. However the sediment type may not be suitable for contaminant analysis in all SMRs. In addition, shellfish sampling in all SMRs might not be possible, due to the lack of mussels in some areas. It may be possible to use PAH data for scallops to improve the spatial coverage for regional assessments; MSS is currently investigating this.

There were significantly more monitoring stations used to assess the concentration of PAHs in the Clyde than the Solway for the Irish Sea biogeographical region for sediment, shellfish and fish.
Concentration of Polybrominated diphenyl ether (PBDEs) in biota and sediment


There are a lack of monitoring data, particularly for sediment in the Scottish Continental Shelf. This is partly due to difficulties sampling in this area and the sediment type which is mainly sandy or rock and therefore not suitable for contaminant monitoring.

The Federal Environmental Quality Guidelines (FEQG) was used in the assessment as there are no OSPAR Environmental Assessment Criteria (EACs) currently available. There is a need for further development of EACs in sediment and biota.

There were insufficient data for the assessment of all SMRs. Additional sampling and analysis would be required if regional assessments were to be made for all SMRs. However, the sediment type may not be suitable for contaminant analysis in all SMRs. In addition, shellfish sampling in all SMRs might not be possible, due to the lack of mussels in some areas. It may be possible to use PBDE data for scallops to improve the spatial coverage for regional assessments, MSS is currently investigating this.

The highest PBDE concentrations in sediment and biota were in the Irish Sea (Clyde and Solway), which includes the Clyde, the most industrialised and urbanised Scottish sea area. The vast majority of monitoring stations in the Irish Sea used to assess PBDE concentrations in sediment and biota were located in the Clyde.
Concentration of Polychlorinated biphenyls (PCBs) in biota and sediment


There are a lack of monitoring data, particularly for sediment and biota in the Scottish Continental Shelf. This is partly due to difficulties sampling in this area and the sediment type which is mainly sandy or rock and therefore not suitable for contaminant monitoring. In addition, there are not enough monitoring data to assess at the SMR scale.

There were insufficient data for the assessment of all SMRs. Additional sampling and analysis would be required if regional assessments were to be made for all SMRs. However the sediment type may not be suitable for contaminant analysis in all SMRs. In addition, shellfish sampling in all SMRs might not be possible, due to the lack of mussels in some areas. It may be possible to use PCB data for scallops to improve the spatial coverage for regional assessments, MSS is currently investigating this.

PCB concentrations in sediment and biota were highest in the Irish Sea (Clyde and Solway), which includes the Clyde, the most industrialised and urbanised Scottish sea area. There were also more monitoring stations in the Clyde than in the Solway for assessing concentrations in both sediment and biota.
Inputs and concentrations of metals in water


Concentration of contaminants in the water column


Monitoring as part of the Water Framework Directive (WFD) is targeted as it is not possible to monitor for all hazardous substances in all water bodies every year. Targeted monitoring relies on knowledge of known contaminant sources and ecological data where there may be unknown pressures. Likewise, certain contaminants have physico-chemical properties that mean they move to sediment or biota and cannot be measured in the water column.

The substances listed as part of the WFD only represent a small fraction of the chemicals that are released into the environment. In addition, less is known about the mixture effects of chemicals in the water column on marine ecosystems; work is currently underway to better understand and quantify mixture effects.

Many of the environmental quality standards (EQS) for metals in marine waters are for dissolved metals (e.g. copper and zinc). At present the Scottish Environment Protection Agency (SEPA) analyse only total metals. This monitoring has in some cases produced results above the dissolved EQS in the Forth and Clyde estuaries, and it is unclear whether collection of dissolved data would produce EQS failures.

The concentration of contaminants in the water column assessment is based on waterbody classifications which cannot be scaled to Scottish Marine Regions. As such SMR status and trends are not presented.

Inputs of mercury (Hg), cadmium (Cd) and lead (Pb) in water


Metal input information was only available from riverine sources where data were collected by SEPA. This aims to represent 80% of major river flows. Whilst this strives to capture the majority of riverine input entering the marine environment, there are no riverine data in some SMRs. The Solway has riverine data.

In addition, it was not possible to ascertain atmospheric deposition data at the SMR scale as the EMEP models present data at the regional sea scale (Greater North Sea and Celtic Seas in Scotland). This presents a major gap as the OSPAR and Marine Strategy Framework Directive (MSFD) assessments have shown atmospheric deposition to be the largest source of some of these metals.

A large proportion of river results were below the limit of detection for all three metals assessed (61% of cadmium samples, 33% of lead samples and 82% of mercury samples). If more certainty is required in understanding riverine metal inputs where riverine concentrations are low, greater analytical sensitivity is required.

The Solway had no status for this assessment in the Marine Assessment, and is listed as having a ‘Lack of evidence / robust assessment criteria’, as are all marine regions for this topic.
  Oil and chemical discharges and releases Data used in the assessment are only available up to, and including, 2016. More recent data, if available, would allow a more up to date assessment to be made, especially of trends.

Current reporting is based on frequency, quantity and nature of the material. For mineral oils there continues to be a lack of assessment criteria.

In 2016 there were a small (< 4%) number of discharges and releases for which the volume was not known. This needs to be monitored as this could represent a significant event.

There can be a data gap in marine oil and chemical discharges and releases of the true volume of litres discharged. As can be seen in the Spills and Accidents section of the Solway Review, out of the 14 spills which occurred in the entire Solway Firth between 2012 and 2017, the litres spills was ‘not known’ on 6 occasions. On one occasion the vessel which was the source was ‘not known’.
  Radionuclides Currently the Radioactivity in Food and the Environment (RIFE) report assesses radioactivity in food and the environment, with a focus on human health. Developments are currently underway to better understand the impacts of radioactivity on non-human species. In addition, work is ongoing to improve radioactivity exposure assessments from discharges of naturally occurring radioactive material from the oil and gas industry.  

Appendix 3 – Research and knowledge gaps

Knowledge Gaps - Clean and Safe - Marine Litter




Scotland’s Marine Assessment 2020 Knowledge Gaps (text either directly from or heavily reliant on Moffat et al, 2020 unless in orange)
Topic & Theme Sub-theme (if there is one) Assessment Identified Knowledge Gap Solway – gaps and notes 
Clean and Safe

Marine Litter

Beach litter


Few beaches in remote areas are monitored for beach litter, particularly on the west and north coasts. Beach litter surveys are infrequent surveys and therefore fail to describe average conditions well. Around the Rhins and Machars the beaches are often ‘hard to reach’. Data collected regarding beach litter may be based on distant visual assessment which risks only large items of litter being noted and cannot account for the full issue of beach litter. Beach surveys are less likely to take place in hard to reach beaches, however a Marine Conservation Society beach clean in 2019 took place on a hard to reach beach near Cairndoon. Accurate recording of microplastics on the UK coast is another data gap. This type of plastic is often overlooked in cleans as they are difficult to gather, count and assess. The Great Nurdle Hunt initiative provides some data.

Mapping of marine litter, such as seen in the SCRAPbook project will only be able to capture information on large coastal litter as the data is based on aerial images. The images were graded by a variety of volunteers, and so personal subjectivity may have led to variability in grading (despite a criteria to grade litter sinks as consistently as possible).

Microplastics in surface water Insufficient spatial and annual coverage due to limited sampling. To make the most effective use of the Marine Scotland ship time available, the microplastics sampling uses the same survey vessel time as for other monitoring. This means that sampling for microplastics has to integrate into other sampling priorities. A baseline does not yet exist for microplastics so a trend analysis is not possible.  
Sea- floor litter The sea-floor litter data were collected during international scientific surveys assessing commercial sea-floor living fish stocks. Trawls take place in areas suited to such fishing and omit deep seas, coastlines, and rocky areas. Likewise the equipment is designed to capture fish rather than litter. The results are, therefore, relative sea-floor litter distributions and are affected by unquantified amounts of sampling bias.

This assessment of sea-floor litter is only as reliable as the quality of the data and the statistical analysis on which it is based.

The trawl gear captures and retains an unknown proportion of the available litter. Actual sea-floor litter densities are therefore higher, potentially considerably higher, than those described in the Marine Assessment.

The data are collected as a part of International Council for Exploration of the Sea (ICES) coordinated international scientific surveys assessing demersal fish stocks. See the section of the Marine Assessment for the potential issues from this data collection method. The limitations of the collection method are all important, but a Solway-specific example was used as an example of the sea-floor bias, as trawls are undertaken on shallow and continental-shelf subtidal sediments omitting coastlines and other sea-floor types, all of which may be differently impacted by litter. For example, over one million tonnes of munitions, which can be defined as litter (UNEP, 2005), were deposited in Beaufort’s Dyke (OSPAR, 2010), an area unsampled in these surveys. To what extent this potentially biased (with regard to sea-floor litter) sampling affects spatial distributions and temporal changes is unknown.

Statistical modelling is subject to assumptions, also available in the sea-floor litter assessment (link to the left).

Overall, the authors feel that this analysis generates ‘broad-brush’ inferences regarding the Scottish Zone between 2012 and 2018 inclusive. The analysis does not enable inferences relating to specific areas or medium or long-term temporal trends.

Marine litter data collected as supplementary to other research or socio-economic activities and therefore may be disproportionately representative of certain areas such as sandy seabed.

Scotland’s Marine Assessment (2020) looked at marine litter on the seafloor between 2016 and 2018, inclusive. The data showed that over the assessment sea-floor litter densities (items km-2) in the Irish Sea (Clyde and Solway) there were apparent reductions in seafloor litter in the region. However, this data may be more representative of the Clyde, as shown in the relevant section of the assessment, there was limited, and in some years no observed presence or absence of litter in sea-floor trawls for the years 2012 to 2018 in the Solway. 



Appendix 3 – Research and knowledge gaps

Knowledge Gaps - Clean and Safe - Microbiology and algal toxins



Scotland’s Marine Assessment 2020 Knowledge Gaps (text either directly from or heavily reliant on Moffat et al, 2020 unless in orange)
Topic & Theme Sub-theme (if there is one) Assessment Identified Knowledge Gap Solway – gaps and notes 
Clean and Safe

Microbiology and algal toxins

  Algal toxins Not all shellfish harvesting sites were monitored for both biotoxins and phytoplankton. Where this was the case, and the frequency of routine biotoxin testing was less than weekly, the lack of phytoplankton counts may have led to toxin events being missed, as no additional biotoxin tests were scheduled. When sites were subject to closure due to the presence of toxins above regulatory limits, testing was not performed for other toxin groups, even when the phytoplankton results indicated an increased risk. Hence, the occurrence of amnesic and paralytic shellfish toxins may have been underestimated, due to extended site closures for diarrhetic shellfish toxins.

Harvesting site closures due to the presence of diarrhetic shellfish toxins usually occur between June and September. Alexandrium blooms tend to happen between April and August, often coinciding with these site closures, so the presence of paralytic toxins in shellfish is likely to be underestimated. Similarly, autumnal blooms of toxic Pseudo-nitzschia species may not lead to additional testing for Amnesic Shellfish Toxins (ASTs). However, shellfish samples must return biotoxin results below maximum permitted levels for all the main toxin groups before sites can open.

One phytoplankton sample is collected at the monitoring point and this is sub-sampled and analysed in the laboratory. It is assumed that the sample is representative of the surrounding seawater, although phytoplankton blooms can be patchy and may form thin layers. Species may therefore be under-represented in the reported cell counts. This is likely to be the case for the benthic dinoflagellate Prorocentrum lima, as this species is rarely abundant in the water column. Environmental information that could be used to inform bloom dynamics is not available at the monitoring points. Water temperature could reveal stratification, and wind direction and speed at the monitoring point could indicate the potential for onshore advection of blooms.

Bathing water microbiology Bathing waters are selected for monitoring and classification when a ‘large’ number of bathers (usually 150 or more) use the waterbody​. There are likely more waterbodies that are used by bathers but fall below the ‘large’ threshold for classification. There are limited data on the bathing water quality of these waterbodies.  
Shellfish water microbiology There are several regions with either no data or very few data points. The Solway is one of two marine regions which have classified production areas but have insufficient data for a regional assessment.  

Appendix 3 – Research and knowledge gaps

Knowledge Gaps - Clean and Safe - Noise


Scotland’s Marine Assessment 2020 Knowledge Gaps (text either directly from or heavily reliant on Moffat et al, 2020 unless in orange)
Topic & Theme Sub-theme (if there is one) Assessment Identified Knowledge Gap Solway – gaps and notes 
Clean and Safe


Continuous noise A lack of reported data from northern and western Scotland and offshore regions constrains understanding in these regions. Marine Scotland is actively engaged in projects to address some of these gap in knowledge.

Knowledge gaps still exist in terms of the thresholds of underwater noise which have deleterious impacts on marine species such as cetaceans, pinnipeds, fish and invertebrates.

Data used in this assessment, from 2013 and 2014, were collected only during the summer months. Continuous noise levels during the winter period have not been assessed. Data were collected during 2015 – 2020 but were not processed and analysed in time for this assessment.

The extent of acoustic masking of natural sounds used by animals (e.g. to communicate, find food and avoid predators) is a major knowledge gap, which will dictate the noise levels at which environmental impacts may occur for different taxonomic groups.

There is little information available about the noise which occurs specifically within the Solway and it’s impacts on the Solway ecosystem and wider marine species. Much of the noise in the Solway will be continuous noise as the Solway generally does not have significant construction or industrial activity.

The topic of noise has extensive knowledge gaps which are outlined in the ‘Filling the Gaps’ page of the noise section of the Solway Review available here.

There are many unknowns regarding thresholds above which noise causes harm to marine species. 

Impulsive noise The coarse spatial scale of reporting of data to the Marine Noise Registry (MNR) means that it has not been possible to assess spatio-temporal variability in impulsive noise.

There is a substantial knowledge gap surrounding impulsive noise for unlicensed activities. For example, there are some geophysical acoustic surveys which do not require licensing, so there is no regulatory control over whether data are submitted to the MNR.

Whilst the MNR enables an assessment of the occurrence of the impulsive noise pressure, there is uncertainty around the magnitude and extent of disturbance and displacement effects caused by that pressure and any impacts at the affected species population level. Work is underway through the OSPAR Intersessional Correspondence Group on Underwater Noise to establish indicators of the risk of impact of the noise pressure on marine wildlife, and the subsequent establishment of threshold values for that indicator.

There are some primary caveats associated with data from the MNR. These are available to read in more detail in the JNCC report Caveats and limitations of Marine Noise Registry Outputs (JNCC, 2018).

The Marine Ecology Monitoring Plan Data from the Robin Rigg Offshore Wind Farm, Scotland provided Solway specific information regarding the impacts of noise from wind farm construction on marine mammals.


Appendix 3 – Research and knowledge gaps

Knowledge Gaps - Healthy and biologically diverse - Species


Scotland’s Marine Assessment 2020 Knowledge Gaps (text either directly from or heavily reliant on Moffat et al, 2020 unless in orange)
Topic & Theme Sub-theme (if there is one) Assessment Identified Knowledge Gap Solway – gaps and notes 
Healthy and biologically diverse


Mammal Cetaceans Offshore cetaceans

The results from large-scale international surveys have greatly expanded the knowledge of the distribution and abundance of cetaceans in the European Atlantic. However, knowledge gaps remain due to the infrequency of these surveys. For logistical reasons, large-scale surveys such as SCANS have been conducted during summer. Information is therefore lacking on large-scale seasonal changes in distribution.

Coastal bottlenose dolphins

The impacts of human activities on these populations are largely unknown, as are the status and population trends for the dolphins on the west coast.

Seals The main knowledge gap is a lack of understanding of the drivers of the decline in harbour seal populations. However, a long term research study is due to be completed in the next few years. This will estimate vital rates in declining and stable populations so that the factors involved can be narrowed down. For grey seal pups, some small colonies are not regularly counted and uncertainty in the estimates could be reduced. In addition, other more appropriate indicators would include at-sea usage and habitat preference. However, this involves more detailed knowledge of foraging and movements and research is continuing. The Solway forms part of the Southwest Scotland Seal Management Unit with the Clyde. In the whole Southwest management unit there was no difference between the number of grey seals counted in 2008 and 2014 despite seeming reductions in inner Solway Grey seal summer abundance. Seal counts in the Clyde may mask changes in the Solway seal count and vice versa.


Birds Abundance of wintering waterbirds There is a lack of knowledge on the key drivers for the declining waterbirds. Most notably waders using non-estuarine (rocky shore) sites.

The reason for the decline in both marine wintering waterfowl and waders since the end of the 1990s is unclear, as are the reasons for the increase in the decades prior to that.

Many of these birds have dispersed populations and are difficult to monitor.

Research is rapidly required across Scotland and indeed throughout their entire global range on waders using non-estuarine coasts, particularly ruddy turnstone and purple sandpiper, to understand the reasons for recent declines and look at possible measures to help populations.

Trends are not currently available for Scottish Marine Regions (SMRs) because the core counts are land based and only have a limited applicability to offshore marine regions. The land-based coverage for SMRs also varies and are currently not set up to be separated into SMRs.

  • Breeding numbers and success trends at a regional (sub-Scotland) level.
  • Breeding numbers and success of shearwaters and petrels.
  • Research on the mechanisms and drivers of changes in seabird populations particularly, climate change, predator-prey dynamics, fisheries bycatch, marine energy collision risk and contaminants.
  • The location of key wintering areas for breeding seabirds.

Trends are not currently available for Scottish Marine Regions. Through the Seabird Monitoring Programme (SMP) only a few sites are monitored intensively annually and more of these would be required for robust regional assessments. Similarly, raw numbers expressed at regional level are incomplete and not comparable across the time period. Comparison is only likely to be possible between full census periods.

Fish Commercial fish The knowledge gaps include current data for predation and natural mortality; the impact of climate change on fish stocks; and comprehensive observer coverage for fishing vessels. It is also not possible to make assessments for Scottish and Offshore Marine Regions (SMRs and OMRs) as these are relatively small compared with the scale at which the stocks are assessed.


Data scales are far larger than the Solway. There is a lot of data for specific species such as cockles which have been surveyed in order to assess stocks and the potential to reopen the fishery, but other stocks lack data. 

The Solway falls entirely in ICES area 7a, which means that both sides of the Firth are included within this data, however the data also includes the rest of the Cumbrian coast, Isle of Man and part of the Welsh, Northern Irish and Irish coasts. Some stock assessments are conducted over a much larger area than this meaning they are not necessarily representative of Solway stocks.

Deep-sea fish Not applicable to the Solway
Inshore fish (estuaries and reduced salinity sea lochs) The WFD assessment of fish communities is limited to six transitional waters only. Other inshore fish communities in coastal areas are not assessed. Inshore fish communities include migratory fish, e.g., salmonids, lampreys, eels, which are subject to pressures out with the region for which there is only limited knowledge. The Solway transitional water fish communities are not assessed as one of the six representative transitional water bodies for the purposes of WFD assessment.

The inshore fish communities in the Solway were not assessed.

Salmon and sea trout There are a number of gaps that could be filled to increase the salmon assessment’s accuracy. However the trends described are supported by independent methods (e.g. counters) and are seen throughout the salmon’s range.

The main gaps exist around the exact drivers of changes, which is the subject of a series of Working Groups/Discussions led by ICES. Scottish Government is focussing on high level pressures impacting on salmon.

The assumption that rod catches reflect sea trout stock status is untested, but reflects best available evidence. International efforts are underway to develop methods to assess the status of sea trout stocks.

Wider fish community Rarest and perhaps most at risk species are not sampled sufficiently well to permit adequate assessment. Current levels of survey effort limit the applicability of analyses to those species that are adequately sampled at these levels of effort. Population levels and distributions of many species are a significant knowledge gap for species in the marine environment, including the Solway Firth. It is unknown if there are spawning sites for Allis shad (Alosa alosa) and Twaite shad (Alosa fallax) in the Solway Firth (these fish are present within the Firth). The possibility of spawning sites has been mentioned in past research but there appears to be no confirmation of this. There is also a lack of data available to show possible spawning sites for elasmobranch species.
Shellfish and other invertebrates Commercial Shellfish For some shellfish stocks there are insufficient data (either fishery sampling and/or survey data) to conduct assessments.

The other main uncertainties are associated with limitations in biological knowledge or stock structure.

Assessments of shellfish are conducted on varying scales, for example Nephrops on Functional Units, for scallop stock assessment is at the Irish sea scale. These varying scales make it difficult to identify Solway specific data and information.

Insufficient data from sampling of landings means that analytical stock assessments have not been undertaken for the Solway Firth region.

Shellfish fished in the Irish sea may be landed outside of the Solway meaning Solway landing data cannot be fully relied upon to represent catch and landing data. 

The Solway is the only Scottish Marine Region not included in the crab and lobster fishery assessment areas in Scotland  

Plankton Plankton The impacts of observed changes in the plankton community on higher trophic levels of the food web is not known.

Lack of monitoring of micro zooplankton, nano/picoplankton, marine bacteria, viruses and fungi means that these components of the plankton community cannot be assessed. Data on the coastal zooplankton community are particularly sparse. There is a lack of plankton community data from the west coast, far west and northern areas, meaning that it is not possible to assess the plankton community in these regions.

Cessation of monitoring will increase the number of regions where there is a lack of plankton community data.

Pressure datasets from other variables e.g. carbonate chemistry, nutrient loading, fishing, seabed disturbance are required.

This assessment has shown that the plankton community in Scottish waters is changing. Further work is required to identify the impact of the observed changes on higher trophic levels of the marine food web, particularly species of commercial importance.

The ability to assess the plankton community depends on maintenance of long term monitoring sites. Collection of plankton samples at the Forth and Clyde has stopped while other sites are at risk. Cessation of monitoring activities will generate gaps in knowledge about the behaviour of the plankton community in some regions.

Pressure datasets from other variables e.g. carbonate chemistry, nutrient loading, fishing, seabed disturbance across all regions are required for these to be included in this assessment.

No Solway specific phytoplankton or zooplankton datasets were used in the pelagic habitat assessment. There is a need for regional data for the Solway Firth and monitoring for change. This information is important in order to highlight potential issues further up the marine food web as plankton is the basis for marine food webs and vitally important


Non-native species Non-native species Key knowledge gaps are: presence and locations of non-native species (NNS) and how quickly they may be spreading; evidence based understanding of impacts on biodiversity in Scotland (or the UK) as most information comes from other countries; known mechanisms of establishment and whether native species disrupted by other stressors, or simply out-competed by NNS; and environmental triggers for the invasive behaviours.

Whilst records of marine NNS have increased since the atlas assessment in 2011, most knowledge has been derived from incidental records and targeted, as opposed to national, survey. In addition little is known about impacts in Scottish waters. The main knowledge gaps are:

  • Baseline information; population estimates/establishment data: records tend to be ‘presence/absence’ data picked up in other monitoring and surveillance programmes, therefore population estimate is a minimum estimate (except when there have been targeted surveys to address outbreaks). Currently there are no criteria for determining when a species is ‘established’ and instead expert judgement on the number of NNS at a site, or whether it is reproducing is relied upon.
  • Lack of information about pelagic NNS in Scottish seas: there are infrequent records of plankton NNS in pelagic waters but on the whole there is no consistent information and impacts are poorly understood.
  • Lack of knowledge on the ecological or economic impacts in Scottish waters: whilst there is evidence from around the world that species in waters with similar environmental parameters can be invasive and colonise, displace, smother, compete with and disrupt native species and habitats, little evidence has been collected their level of establishment and  impacts in Scotland or the UK. Similarly there is little understanding about the behaviour of the NNS, especially of what triggers them to become invasive.
  • Mechanism of establishment of NNS: there is some evidence to suggest that marine NNS are more likely to be established in areas where the environment is impacted by other pressures. However, it is difficult to know whether this is a reflection of the types of activities that introduce NNS or, whether the NNS have taken a competitive advantage over the native biota in a damaged system.
There are many data gaps in marine invasive non-native species (INNS) data. Baseline information about INNS is scattered and variable depending on the area. In the Solway Firth there is a biosecurity plan which is updated by Solway Firth Partnership every three years (currently 2021-2024 available here). It is updated with the most recent data as well as species recorded on annual monitoring panels placed in Solway harbours and marinas. The Solway, therefore has local information which helps assess the potentially growing threat of INNS. Furthermore, Solway Firth Partnership’s marine INNS identification guide has helped positively identify new INNS in the Solway, with the Japanese skeleton shrimp identified in Stranraer. However, lack of awareness/ knowledge of marine INNS means that species may be unrecorded. Data on marine INNS tends to focus on the presence/absence of INNS, meaning that the population size and population growth may not be monitored. Finding marine INNS can be a challenge, with transport and establishment occurring in the marine environment, therefore the current exact species and presence of INNS is also a data gap.

Appendix 3 – Research and knowledge gaps

Knowledge Gaps - Healthy and Biologically Diverse - Habitats & Conservation



Scotland’s Marine Assessment 2020 Knowledge Gaps (text either directly from or heavily reliant on Moffat et al, 2020 unless in orange)
Topic & Theme Sub-theme (if there is one) Assessment Identified Knowledge Gap Solway – gaps and notes 
Healthy and Biologically Diverse


Deep-sea Predicted extent of physical disturbance to the seafloor Increased availability and improved resolution of habitat survey data and fisheries data would improve the accuracy of indicator results. Scottish Government have made a commitment (Scottish Government, 2019) for introducing tracking technology for vessels less than 12 m which will result in significant improvements in the inshore waters in future. In situ monitoring data could be used to assess habitat condition over time in a different way, and also assess the accuracy and inform future development of this type of proxy assessment.

The indicator currently only considers disturbance from surface and sub-surface abrasion caused by reporting vessels (those over 12 m in length and using VMS) fishing with bottom contacting gears (considered to be the most significant pressure); however, there is an ambition to add other pressures in the future. Data were not available for some bottom contact fisheries, most notably smaller vessels (<12 m) operating mainly in coastal waters that are not equipped with a Vessel Monitoring System (VMS) transmitter. This means disturbance maps may be an underestimate in some locations. The pressure maps used show aggregated fishing pressure across a large grid cell; is not possible to determine if the same level of disturbance is actually present across the entire cell.

There is low confidence in the habitat data used across a large amount of the assessed area as it is based on models, but medium to high confidence in well surveyed areas such as within Marine Protected Areas. Confidence in the sensitivity scores used depends on the level of data used and the quality of information available on the resistance and resilience of habitats and species to physical damage pressures. Sensitivity scores derived from experimental or field survey studies have high confidence, whereas scores based on expert judgments have low confidence.

Pelagic environment Case Study: Marine Food Webs No knowledge gaps provided  
Intertidal and continental shelf Biogenic habitats Whilst our knowledge-base has improved considerably over the last 10 years, a more detailed understanding of the distribution and extent of biogenic habitats within each of the SMRs is still required. Such data are needed to underpin any future application of a biogenic habitat extent indicator in Scottish waters (whether in the current combined format or perhaps a modified approach using habitat-specific assessments) and the continued use of the stringent UK ‘no loss’ target. Studies are also needed to determine the scale; nature and cause of natural temporal fluctuations in habitat extent and condition (compared with anthropogenic factors).

In identifying knowledge gaps, it is considered that this should relate to the broader issue of future assessment of the status of biogenic habitats rather than the narrow approach that has been adopted in the current assessment which deals specifically with habitat extent. Ideally, condition measures should also contribute to future quality assessments.

It is currently impossible to produce estimates of habitat loss for regions with a high degree of confidence because of the paucity of information on the distribution and extent of most of the biogenic habitats, particularly maerl, seagrass, blue mussel and horse mussel beds. An understanding of the scale and processes governing natural temporal fluctuations in extent and condition measures would help place recorded changes into context. Better correlation between observed changes and anthropogenic drivers are also required and this could be aided by inclusion of monitoring sites at clear risk of anthropogenic influence or where such pressures could be quantified (e.g. sites in the vicinity of fish farms or with fishing pressure data – for both mobile and static gear).

Baseline extent measures (ha) for biogenic habitats in the Solway is largely unknown throughout the Solway.  

Biogenic habitat loss in the Solway is unknown. 

There is conflicting information regarding horse-mussel beds. In Scotland’s Marine Assessment tables; ‘Baseline extent measures (ha) for biogenic habitats within Scottish Marine Regions’, ‘Loss of biogenic habitat extent (ha) within Scottish Marine Regions recorded in 2011 – 2018’ and ‘Percentage and total loss of biogenic habitat extent within Scottish Marine Regions based on comparison of 2011 – 2018 extent estimates with baseline values.’ horse-mussel beds are classed as ‘unrecorded’ in the Solway despite their presence being noted in the past.

Intertidal seagrass There are a lack of data and knowledge available for Scottish intertidal seagrass in order to carry out an assessment for SMRs. Not only is there a lack of comprehensive baseline data but there is no long-term understanding of ecological trends of Scottish seagrass. SEPA has begun the process of assessing intertidal seagrass at a select number of sites but these are not representative of Scottish seagrass beds as a whole.


Knowledge of seagrass density and loss around Solway coast is poor and limited. 

There needs to be a full Solway Firth assessment of seagrass to assess a baseline and the condition of existing seagrass beds and measure future loss or growth. 

Predicted extent of physical disturbance to the seafloor See Habitats, Deep-sea, Predicted extent of physical disturbance to seafloor above
Healthy and Biologically Diverse


Marine Protected Areas (MPAs) As the MPA monitoring strategy follows a risk-based approach not all sites have been monitored since the last assessment. The ongoing monitoring programme will allow a more thorough assessment of whether individual MPAs are achieving their objectives by the time of the next report to parliament in 2024.


Current use of the estuary by European Smelt needs more research. The Marine Conservation Zone (Cumbria) will help further research and understanding of Solway estuary use by European Smelt.

As pointed out in the Clyde Marine Region Assessment (Mills et al, 2017), more research into the ecological connectivity of features within and between sites and between sites and the wider marine environment would be beneficial. This may provide opportunities to enhance and better protect connectivity and therefore, ecosystem services and resilience. 

Case Study- Priority Marine Features (PMFs) Between now and the next assessment of the status of Scotland’s seas it is expected that the gaps in knowledge of PMFs will be addressed, for example in the distribution of habitats outside the MPA network. This will help underpin future assessments of status, and also of the effectiveness of any management measures for some of the most sensitive marine life, such as biogenic habitats.  

Appendix 3 – Research and knowledge gaps

In-text References

JNCC (2018). Caveats and limitations of Marine Noise Registry Outputs. UK MNR 2017 Output Document. Available here. (Accessed: 10.04.21)

Moffat, C., Baxter, J., Berx, B., Bosley, K., Boulcott, P., Cox, M., Cruickshank, L., Gillham, K., Haynes, V., Roberts, A., Vaughan, D., & Webster, L. (Eds.). (2020). Scotland’s Marine Assessment 2020. Scottish Government. Available here. (Accessed: 10.04.21)

Mills, F., Sheridan, S. and Brown S., (2017). Clyde Marine Region Assessment. Clyde Marine Planning Partnership. pp 231, Available here. (Accessed: 14.05.18)

OSPAR (2012). JAMP Eutrophication Monitoring Guidelines: Chlorophyll a in Water. OSPAR Agreement 2012-11. (Direct download) Available here. (Accessed: 14.05.21)

OSPAR (2010). Overview of Past Dumping at Sea of Chemical Weapons and Munitions in the OSPAR Maritime Area: 2010 update, OSPAR Commission. Available here. (Accessed: 14.07.21)

Scottish Government (2019). Future of fisheries management in Scotland: national discussion paper, Scottish Government. Available here. (Accessed: 14.07.21)

UNEP (2005). Marine Litter: An analytical overview, Nairobi: United Nations Environment Programme.


Image; Thrift on the coast below Dunskey Castle. © G. Reid/ Solway Firth Partnership.