Impact case study database

The UK aquaculture industry is undergoing rapid expansion whilst adhering to strict environmental regulators to avoid environmental harm. Every salmon farm requires a license from the regulator, SEPA, to operate commercially; and SEPA specifies environmental quality standards for sea-floor sediments, enforced for all aquaculture sites [5.1]. SEPA provides guidance and support to enable businesses to estimate benthic impacts by site-specific modelling [5.2] and new regulations issued in 2019 made modelling near-field waste a compulsory part of the planning application process for new or expanding farms. NewDEPOMOD is the only named approved modelling tool [Section 7, 5.3]. Therefore, UK salmon production is currently underpinned by NewDEPOMOD. The Scottish Salmon Producers Organisation (SSPO) has identified NewDEPOMOD as a key tool to help unlock further capacity for the industry as it moves towards its 2030 target of doubling fish production [5.4]. NewDEPOMOD has been available through user licences since 2017; SSPO currently has seven members, which between them hold a total of 47 NewDEPOMOD licenses [5.5]. All SSPO operational salmon sites in Scotland are using NewDEPOMOD to match farm production to environmental capacity, allowing maximal farm production while ensuring environmental standards are maintained. Due to the enhanced capabilities of NewDEPOMOD, SEPA are now able to consent farms greater than the previous fixed limit of 2500 tonnes. NewDEPOMOD therefore directly creates value for industry. Industry commitment to NewDEPOMOD is evidenced through SSPO’s considerable investment in ExPAND and ExPAND2 research projects.

MOWI Group is the largest global producer of farmed salmon and one of the top three largest salmon companies in Scotland. It has used NewDEPOMOD since its launch in 2017, calculating that the model directly enabled an increase in production by 5,600 tonnes every 2 years, with estimated additional annual profit of £3.36m [5.6]. Dr Philip Gillibrand, MOWI Oceanography and Modelling Manager, states: “the application of the [NewDEPOMOD] model has contributed to the company’s growth over the past two years and is a vital part of the company’s future growth and development plans” [5.6].

Alongside and directly inspired by the UHI-SAMS development of NewDEPOMOD, there has been independent development of specialised applications for alternative aquaculture systems, locations, and species. TROPOMOD has been developed for aquaculture in Asia [5.7] and has provided the integral impact modelling in the AQUAPARK project, a scheme for planning and management of aquaculture parks in the Philippines [5.8]; TROPOMOD is currently being used in all planning, regulations, and licensing of aquaculture in Philippines. MACAROMOD has been developed for offshore aquaculture industry in Macaronesia [5.9] and is being integrated into their industrial practise and regulation. These initiatives have been developed from AutoDEPOMOD but due to third party software redundancies are in the process of being updated to the NewDEPOMOD platform, which is essential to their continued use. Ongoing developments to integrate country-specific and species-specific applications into the NewDEPOMOD package have led to salmon-producing countries such as Canada, Chile and Norway also trialling the tool. UHI-SAMS Research Services Ltd (SRSL) delivered in-person training for four people from four consultancy firms in Chile in late 2019, with training for a further 23 delegates booked for the first quarter of 2021. Since the start of 2020, there have been thirteen enquiries from Chile alone about NewDEPOMOD, and a research collaboration forged with Norwegian companies Aqua Kompetense and Akvaplan-niva. NewDEPOMOD currently has 62 international licenses active, and a further 12 ongoing licence enquiries. UHI-SAMS is receiving increasing numbers of enquiries for research projects, training, license sales, and regulatory management from countries including Australia, Canada, USA, France, and within the Aquaculture Stewardship Council (ASC) [5.5].

The research, development, and improved workability of NewDEPOMOD over the past five years have turned the tool into a powerful commercial asset, and SRSL has highlighted NewDEPOMOD as a key commercial product in its business plan [5.5 and 5.10]. UHI-SAMS has employed a project manager and two modellers, with additional input from a research-focused science lead (10% FTE) and up to ten researchers. DEPOMOD and AutoDEPOMOD were free to download, and now NewDEPOMOD annual licenses are sold for £3,250 (academic), £2,500 (developer), or £6,500 (commercial) per license. Many licences are renewed annually to generate reliable and repeatable income. The total commercial income for 2017-2020 was £207,840.83, contributed by licence sales, training, and commercial modelling projects. With the inclusion of research funding totalling £2,164,806.50 for the same period, NewDEPOMOD has generated a combined commercial and research total income of £2,372,647.33.

UHI research into HABs provides benefit for two main stakeholder groups: 1) the Scottish aquaculture industry and its consumers, through early warning systems, and 2) governmental regulators and policy makers for finfish and shellfish aquaculture in the UK and internationally.

4.1 Early warning/risk assessment of HABs & biotoxins for the aquaculture industry

The Scottish aquaculture industry produces more than 9,000 tonnes of shellfish each year, equating to three million portions consumed worldwide annually. Confidence in the aquaculture industry was damaged in 2013 when 70 people were poisoned by biotoxins generated by HABs in mussels harvested in Shetland and served in London restaurants. A direct impact of the post-2014 application of this research has been to minimise the potential for further human poisoning incidents in Scotland, the UK and elsewhere, with no reported human poisoning cases from algal biotoxins in Scottish shellfish since then.

To achieve this, the UHI team has deployed its research outputs to develop an early warning system that gives aquaculture companies notice of predicted HABs and biotoxin levels in the week ahead. After consultation with the trade groups Seafood Shetland and the Scottish Shellfish Marketing Group, in 2015 the SAMS group was funded by Seafood Shetland to produce weekly risk assessment bulletins for the Shetland Islands, an area that accounts for ~75% of national shellfish production. These bulletins are similar to weather forecasts, relying on research-based understanding of the environmental drivers of harmful blooms, mathematical models and individual research expertise to interpret the data and modelled predictions to produce a forecast risk assessment for the coming week. In 2016, the researchers extended this service to cover all of Scotland and moved to web dissemination via www.HABreports.org with the inclusion of mathematical model-based HAB predictions.

These risk assessment and forecast tools draw on the results of the research described above [3.1-3.6] and other SAMS work. They allow the industry to manage risk to their businesses and – as required of them as Food Business Operators – to human health, too. If levels of HABs or biotoxins are predicted to increase, shellfish harvesters can undertake precautionary end-product testing, move harvesting operations to another location, or cease harvesting temporarily altogether [5.1-5.2]. The predictions generated by the SAMS’ models are also relevant to the finfish component of the industry: if fish killing species are forecast, businesses can deploy protective skirts or bubble curtains, modify feeding regimes, or move fish cage locations. The weekly risk assessment bulletins are sent to 57 recipients including 100% of Shetland’s shellfish growers, the multi-national salmon producers Grieg Seafood and Scottish Sea Farms, and the Scottish Shellfish Marketing Group.

Ruth Henderson Chief Executive of Seafood Shetland states: “As HABs precede shellfish toxicity, early warning of their anticipated appearance permits our members in the shellfish industry to plan their harvesting operations in conjunction with their customers; this reduces the likelihood of human health incidents but also addresses business risk by allowing more informed husbandry and minimising expensive produce recalls. The financial saving of your early warning models and bulletins to the industry could therefore easily run into the £100s of thousands per annum” [5.1]. Michael Tait, Chairman of the Scottish Shellfish Marketing Group, also says that the bulletins have “been of much use to the aquaculture industry in this region” and provided “a financial benefit to our business development” [5.2].

4.2a Regulatory monitoring: UK

Competent authorities in EU member states – including Food Standards Scotland (FSS) – monitor classified shellfish production areas in compliance with the EC regulation 854/2004, for the presence of biotoxin producing phytoplankton and the levels of biotoxins. It is not possible, logistically or financially, to monitor all shellfish harvesting sites at a high enough resolution to protect human health. As a result, FSS is obligated to make scientifically based decisions on the location and frequency of sampling of ‘representative monitoring points’, each of which is used as a sentinel site for a number of harvesting locations. Factors influencing this decision-making process include: the location of sites and their proximity to others, hydrography, historical HAB/biotoxin records, ecology of local HABs, and the shellfish species farmed. An overriding requirement is that the risk of not detecting biotoxins concentrations in shellfish flesh in excess of the maximum permissible level is below 1%. Using knowledge of HAB ecology and biotoxin chemistry, the UHI research was able to determine which organisms should be included within the monitoring programme [5.3] and allowed development of statistically-based mathematical models [3.7] that are now used by FSS to design the spatial distribution of the representative monitoring points within the programme to minimise health risk to consumers [5.4]. In 2014, this research was used by the UK National Reference Laboratory for Marine Biotoxins to set the regulatory threshold for both Alexandrium and Pseudo-nitzschia above which action is taken within the monitoring programme [5.5, item 2.2, pages 2-4]. UHI’s research has therefore maximised the health protection provided by the programme within available resources.

Via SAMS’ commercial arm (SRSL), UHI operates, under contract, the harmful phytoplankton monitoring component of the FSS regulatory shellfish safety monitoring programme outlined above. The team analyses water samples collected on a weekly basis from 40 monitoring sites around Scotland. Since 2014, the team has analysed (by August 2020) 9,788 samples and found 4,641 instances of dangerously high algal cell densities. FSS relies on UHI’s research and subsequent expertise to interpret sometimes ambiguous results, by evaluating the magnitude of the risk from bloom events beyond the information provided by cell counts alone. For example, previous UHI research has shown the toxic diatom Pseudo-nitzschia is present in Scottish waters in either the more toxic ‘seriata’ group or less toxic ‘delicatissima’ group. SAMS is therefore able, on a day-to-day basis, to advise FSS on whether Pseudo-nitzschia blooms are high or low risk. In combination with toxicity data, FSS then allows or prohibits shellfish harvests accordingly. Dr Jacqui McElhiney, Head of Food Protection Science & Surveillance FSS, says: “SAMS particular scientific expertise has guided and supported the programme” and “enhanced risk assessment” [5.4].

This research has also directly influenced the way regulators and policy makers (the Scottish Environment Protection Agency (SEPA) and Marine Scotland (MS)) inform the public about HAB and biotoxin risks. In 2016, SAMS shared with SEPA its findings that a significant, so-called “red tide” bloom of the fish-killing dinoflagellate Karenia mikimotoi was developing in the Clyde Sea, together with a research-based interpretation of the likely cause and impact of this event. Pre-warned, SEPA was able to reassure the public that the subsequent observed mass marine faunal mortalities were not a direct result of any discharge from a regulated business or a human health concern [5.6].

MS also uses this research to support policy. For example, the research is important to MS’s climate change advice adaptation plans [3.3, 5.7]. Dr. Eileen Bresnan of MS says: “These studies make an important contribution to Marine Scotland as they feed into the development and implementation of climate change adaptation plans for the aquaculture industry by the Scottish Government” [5.7]. Application of UHI’s research through the HABreports web site also supports MS’s ten-year Farmed Fish Health Strategy by providing both long term and real time information to improve the health and wellbeing of farmed fish and underpin the sustainable economic development of the industry. Dr. Bresnan also says: “Prof. Davidson’s group provides the only mechanism which has already been successfully implemented in Scotland to provide this real time [HAB] information”. “The development of the HABreports website by Prof. Davidson’s group ( https://www.habreports.org/), where the risk from [fish killing] Karenia mikimotoi blooms is evaluated and presented, represents a considerable resource to Marine Scotland. It allows the Marine Scotland Fish Health Inspectorate to provide the most up to date advice to the Scottish aquaculture industry” [5.7].

4.2b Regulatory monitoring: International

SAMS’ research, and the subsequent expertise based on the results of this research, have also been used to set evidence-based, pan-European guidance on which harmful phytoplankton and biotoxins should be monitored and how this monitoring should be undertaken in the EU. In 2018, on the strength of his research and monitoring expertise, Prof. Davidson was invited to join a panel of seven experts asked to draw up a new technical guide on the principles of good practice in toxin-producing phytoplankton monitoring for the EU [5.8]. The guide is designed for use by the competent regulatory authorities in all EU member states to standardise their monitoring practices and embeds good practice established in Davidson’s research e.g. [3.4 - 3.7]. Formal publication is awaiting agreement of all EU member states, the UK’s adoption of the guide is confirmed by [5.9].

The precipitous decline and near extinction of South Asia’s three Gyps vulture species in the past 25 years, from many tens of millions to just a few tens of thousands of individuals, is not purely a conservation issue. Vultures provide multiple essential ecosystem services, not least by rapidly removing carrion and associated zoonotic risks to human health. The ‘cost’ of vulture losses in South Asia will be felt for many decades to come, from a human health, waste management (cost), cultural and biodiversity loss perspective. One article (Markandya et al., 2008, Ecological Economics, 67, 194) regarding impacts in India alone, has placed the ‘cost’ to human health from vulture declines (between 1992-2006), principally due to increased scavenging dogs and resulting rabies transmission to humans, at ~$34 billion (US$).

The research highlighted here, in seeking to halt this biodiversity loss, has: armed NGOs with the primary data they need to persuade governments to (4.1) strengthen laws that ban or restrict NSAIDs in India, specifically to protect vultures; (4.2) supported action regarding veterinary NSAIDs across Europe to protect vultures and other avian scavengers; (4.3) informed and influenced international multi-species action plans aimed at securing global vulture population recovery; and, (4.4) built robust NSAID monitoring and analytical capacity in multiple countries within South Asia. As a result, there are now positive early signs of vulture population recovery, and release programmes have been stepped up as a safer environment for these species re-emerges.

4.1 Strengthening laws in India to eliminate illegal veterinary diclofenac use

Comprehensive carcass survey data for India published in 2014 – critical to protect vultures and allow population recovery – proved that existing bans on veterinary diclofenac had not stamped out its use [3.1]. It allowed the collaborative partnership SAVE – ‘Saving Asia’s Vultures from Extinction’, within which UHI is a research partner – to exert pressure on the Indian government to tighten laws. Within ~6 months of publication, this study’s findings were a central piece of evidence used by SAVE to lobby Indian authorities to ban large, 30ml, multi-dose injectable vials of diclofenac [5.1a]. Millions of these were being sold each year, labelled ‘for human use only’, but farmers were widely using them illegally on livestock. In July 2015, the Indian Health Ministry banned these vials across India, restricting all diclofenac vials to just 3ml, rendering them impractical for use on large animals. Dr Chris Bowden, RSPB Globally Threatened Species Officer and SAVE Programme Manager who led the call to ban these large vials, said: “the data provided by carcass surveys was absolutely critical to help drive this legislative change, and without this robust research data, the ban would not have occurred” [5.2]. Further, he noted that a subsequent unsuccessful appeal against this ban to the Madras High Court, brought in 2016 by certain drug companies [5.1b] “would undoubtedly have succeeded in over-turning this ban, had this very clear research evidence base not been in place” [5.2].

4.2 Informing European policy to mitigate NSAID risks to European avian scavengers

In late-2014, the European Commission (EC) expressed its concern about the potential impact that diclofenac and other NSAIDs could have on vultures and scavenging birds in Europe. This followed the widely criticised emergence of veterinary diclofenac onto the EU market in 2013, particularly in Spain, which is Europe’s primary vulture stronghold. The EC asked the European Medicines Agency (EMA) to consult, consider risks, and report back. The subsequent assessment drew heavily on the research carried out and published by Taggart and colleagues [5.3]. Specifically, it highlighted [3.2], which reported the first (and then only) European wild vulture NSAID poisoning case, stating that it directly supported “the hypothesis that the exposure routes described are realistic” within the EU [p21 and p24; 5.3]. Also, in commenting on the relevance of Taggart’s research to the EMA process, the Vulture Conservation Foundation (VCF) stated that it provided “clear and indisputable evidence that medicated carcasses are available to and being consumed by scavenging birds in Europe” [5.1c]. The EMA concluded that “diclofenac use in animals posed a risk to European vultures” and recommended that various “measures are put in place to better protect the birds” [5.4]. Hence, in 2015, the EC asked all relevant EU member states to draw up National Action Plans to mitigate against these risks. This has now been undertaken in 12 EU countries [5.5; p12 and 13]. Mitigation measures adopted vary by country, and include: providing better risk guidance/information to vets, adding specific warnings regarding risks to wildlife/vultures to product packaging/literature; enforcing strict controls regarding fallen livestock on farms; and, instigating new monitoring schemes to test carcasses available to scavenging birds. The current guidance enforced in Spain, for instance, requires clear labelling and provides guidance about limiting NSAID exposure to wildlife [5.6].

4.3 Influencing internationally adopted, multi-species action plans to conserve vultures

Taggart’s research has also informed and influenced a major international action plan aimed at conserving vultures. A “Multi-Species Action Plan (MsAP) to Conserve African-Eurasian Vultures” was adopted in 2017 by the UN Global Convention on Migratory Species (CMS). The MsAP sets out to reverse population declines of 15 vulture species, the most threatened group of terrestrial migratory birds on Earth [5.7]. In the plan, [3.1, 3.2, 3.3 and 3.4] are cited in support of one of twelve core global objectives: “To recognise and minimise mortality of vultures by non-steroidal anti-inflammatory drugs (NSAIDs) and occurrence and threat of toxic NSAIDs throughout the range covered by the Vulture MsAP”. Most specifically, the MsAP [5.7, p59] highlighted the research noted here on flunixin [3.2], nimesulide [3.3], and aceclofenac [3.4], as these studies represented the most concrete evidence that these NSAIDs also posed risks similar to that of diclofenac. NSAIDs were then ultimately listed in the MsAP as the only ‘critical’ and primary threat to vulture species in South Asia, and, an additional ‘high’ threat across Europe, Central and East Asia (Global Threat Priority Map [5.7, p57]). Regarding the relevance of Taggart’s research to the final MsAP objectives, Dr Roger Safford - Senior Programme Manager for Preventing Extinctions at BirdLife International - the primary author of the NSAID sections within the MsAP, said it: “…directly informed…and thus shaped the proposed conservation actions to counter this threat, not only in South Asia but across the Old World. Without it, there would have been insufficient evidence to include NSAIDs other than diclofenac as threats, and so the MsAP actions in relation to these drugs would have been flawed” [5.8].

The impact of the MsAP in relation to NSAIDs will be measured every six years, in 2023 and again in 2029. This will be assessed in part by the “number of CMS Parties and Range States to have banned or voluntarily withdrawn potentially harmful NSAIDs for veterinary use and introduced safe alternatives” [5.7, p95, Objective 2]. Since the MsAP was first mandated by the CMS in 2014: India banned multi-dose vials of human-use diclofenac in 2015 [5.1a]; Iran banned veterinary diclofenac, also in 2015 [5.1d]; Cambodia followed suit in 2019 [5.1e]; and, Bangladesh has entirely banned the diclofenac ‘pro-drug’ aceclofenac [3.4; 5.1f] and partially banned ketoprofen, another vulture-toxic NSAID, within its “Vulture Safe Zones” that encompass ~25% of the country [5.1f]. On the ground in South Asia, such action is now also starting to result in encouraging early signs of vulture population recovery in parts of both India and Nepal [5.9], i.e., “for the white-rumped vulture there is now strong evidence….that a decline up to about 2013 has given way to a rapid increase from about 2013 to 2018” [5.9, paper 1, p97]. Further, it has now been deemed safe enough to begin to release precious captive and captive-bred Gyps vultures back into the wild to assist population recovery, with releases starting in Nepal in 2017 [5.1g] and in India in 2019 [5.1h].

4.4 Capacity building to support robust NSAID monitoring within South Asia

In 2012, Taggart demonstrated that a sensitive, low-cost ELISA could be used to screen carcasses of vultures or their food for diclofenac [3.6]. The test was validated in India by Taggart and colleagues at the Indian Veterinary Research Institute (IVRI; India’s premier Government veterinary research establishment). Staff at IVRI and at the Bombay Natural History Society (BNHS; one of India’s largest conservation NGO’s) were trained by Taggart to undertake this test. Training is supported by a freely available manual compiled by Taggart and colleagues [5.10]. In 2014, this new capacity allowed IVRI to make a discovery with potentially global implications. They published the first evidence that diclofenac may also be deadly to other raptors, identifying clinical signs of diclofenac poisoning alongside diclofenac residues (detected by ELISA) in steppe eagles found dead in Rajasthan [5.11]. In a press release regarding this finding, Birdlife International said: “With fourteen species of Aquila Eagle distributed across Asia, Africa, Australia, Europe and North America, this means that diclofenac poisoning should now be considered largely a global problem” [5.1i].

Taggart has also been working with multiple SAVE partners in South Asia to transfer knowledge regarding NSAID monitoring and analysis, ensuring that techniques used in [3.1-3.6] are applied in-country to gather data consistently and reliably. This is critical if the research evidence generated in South Asia is to be used by NGOs to persuade governments to change laws and ban or restrict NSAIDs. Taggart has trained staff at: IVRI (5 staff) and BNHS (>10) in India; the International Union for Conservation of Nature (IUCN) in Bangladesh (>10); Bird Conservation Nepal and the National Trust for Nature Conservation in Nepal (8); and, provided training resources – both written guidance and equipment - to the World Wildlife Fund for Nature in Pakistan. Collectively, this work is enabling more and improved data gathering, and helping to create a clearer picture of the NSAID risks present in each country. This work has been funded by the RSPB and more recently through SFC-GCRF funding to UHI. Such activity is also agreed within and guided by the SAVE 24-partner consortium, within which Taggart sits on the Technical Advisory Committee. Prof. Rhys Green – Professor of Conservation Science at University of Cambridge, and SAVE Chairman said that Taggart’s research “has played a vital part in the conservation of these species and continues to do so”, and that his engagement in capacity building has been “essential in ensuring that survey design and protocols for collecting, storing and processing samples were fit-for-purpose in the challenging physical and cultural environment of South Asia” [5.2].

The UK is the main country in Europe catching Nephrops and is responsible for 60% of the total landings, the remainder being caught (in declining importance) by vessels from Denmark, Ireland, France, Sweden, the Netherlands, Belgium, Germany, Norway, Spain and Portugal (based on 2018 landings data from ICES). Dublin Bay prawns are thus a particularly important fishery for the UK where they are caught by trawls and creels. Trawling accounts for the bulk of the landings at around 75% by value i.e. £60 – 75 million per annum (Marine Management Association UK Sea Fisheries statistics).

Recognising the importance of the prawn fisheries, Dr Fox organized a workshop in May 2014 that brought together a wide range of stakeholders, including fishery scientists, policy makers, industry representatives, and NGOs to discuss issues facing the sector. At the workshop, industry representatives expressed strong concerns about the impact of the EU landing obligation, which was due to be introduced over the next few years, and presented the case that post-discard survival of Nephrops was much higher than the 25% figure commonly assumed at the time by fishery bodies such as ICES.

4.1 Regulatory impact

Fox and Albalat’s subsequent research confirmed that survival of Nephrops is, indeed, higher, typically more than 50%. The Scottish Government submitted the results from the UHI and Stirling Universities research as evidence to the EU Fisheries Commission in 2018. The Commission in turn asked its Scientific, Technical and Economic Committee for Fisheries (STECF) to review the evidence. An exemption was granted in 2018 on grounds of high survivability, ahead of the full implementation of the discard ban [5.4, 5.5]. In recommending approval for the exemption, STECF concluded: “The supporting scientific information is of good scientific quality and is based on state of the art methods (“as recommended by the ICES Working Group on Methods for Estimating Discard Survival”) and “the approach chosen to try to validate how representative the captive survival estimates were of the wider fleets is commendable” [5.1, p139].

In February 2019, Paul McCarthy of Marine Scotland’s Discards Team stated via the Fisheries Innovation Scotland’s (FIS) project portfolio impact evaluation report [Anderson Solutions & O’Herlihy & Co Ltd confidential report to Fisheries Innovation Scotland mentioned in email 5.2] that: “The [UHI/Stirling] research [funded] from FIS was a key component of the case that Marine Scotland put forward to argue for a High Survival exemption for Nephrops caught in trawls in both the North Sea and North Western Waters. The research formed the evidence base on which we were able to show than more than 50% of discarded Nephrops did survive and were capable of contributing to the overall biomass. The complete [research] report was sent to STECF where it was reviewed. STECF assessed it as methodologically sound and its conclusions were considered convincing. Without the research we would not have been able to secure the Nephrops high survival exemptions.” [5.2]

Broadening the geographic impact of the research, Fox and Albalat further collaborated with Cefas and the Swedish University of Agricultural Sciences in bringing together and comparing prawn survival data from the west of Scotland with North Sea studies. This inter-study comparison was recently published in the peer-reviewed scientific journal of the intergovernmental body ICES [3.4], further strengthening the evidence underpinning the survival exemptions for both sea areas.

Richard Holburn, Marine Scotland Policy Officer stated in Nov 2019: “The granting of this [ Nephrops discarding] derogation was particularly useful for all those involved. By combining the derogations into one [covering both the North Sea and North Western Waters] it made things simpler for stakeholders to follow and comply with, reducing the possibility of enforcement action and any confusion as to which derogation was being utilized at the time of inspection. The simplification also benefitted policy colleagues as it made negotiations simpler by referring to one exemption” [5.3, 5.4, 5.5].

4.2 Financial and other impacts on the industry

The UK industry estimates the exemption has saved it significant amounts of money and additional practical problems. Because the exemptions were granted, precise costs which would have been incurred in disposing of unwanted Nephrops in accordance with the landing obligation are not available, but a study by the government’s Cefas body has estimated that the average costs across the industry of disposing of unwanted material which would have to be landed (without the derogations) would be £9,900 per fishing vessel per year [5.6 p24]. Disposal costs are particularly high because the waste must be stored separately from the human food-chain and disposed of in accordance with strict regulations.Storage and disposal costs for geographically remote landings ports, such as in the west of Scotland, would likely be even higher. Given that 164 UK prawn trawlers fish the waters where the exemptions apply (West Scotland and North Sea), there is an estimated saving of £1.6m per year across the entire UK fleet. Such additional costs would fall to the catching vessels and would have been difficult to bear, especially for smaller operators and those working in remote regions. The derogations will also have resulted in similar cost savings for other countries fishing in the North Sea in particular, but it has not been possible to find comparable waste disposal costs in order to estimate those additional savings outside of the UK.

Financial savings are in addition to the removal of operational difficulties mentioned above by Richard Holburn [5.3]. Furthermore, Ian Wightman, a small trawler operator in the Clyde and member of Clyde Fishermen’s Federation, stated in January 2020: “The derogation has been a keystone in maintaining our ability to continue fishing unhindered. It has been fundamental in showing that our current methods are extremely selective and sustainable, it has helped to show certain groups that we do not catch a large amount of undersized stock. The project has stopped the realistic possibility of a large financial burden disposal of any catch. The mental burden of having to comply with unworkable burdens should not be underestimated.”

4.3 Conservation benefits

There has been a conservation impact as well. UHI and Stirling Universities’ research in the offshore fishery showed that trawlers typically discard up to 5,000 small Nephrops per day [3.3]. Assuming a trawler typically fishes for 200 days per year, under the terms of the survivability exemption, UK trawlers continue to return an estimated 260 million young prawns to the ocean each year. The research suggests that over half of these discarded animals survive, animals that otherwise would have been brought to port and killed un-necessarily. These young animals will continue to grow and contribute to the long-term sustainability of the stocks.