Evaluating the Environmental Conditions Required for the Development of Offshore Aquaculture

Lead Research Organisation: University of Stirling
Department Name: Institute of Aquaculture


Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

Technical Summary

There is a demand to increase the capacity of UK finfish aquaculture. However, development is limited by the lack of further suitable farm sites within the fjordic sea lochs of the Scottish west coast where the majority of the industry is based.

Fjords provide relatively sheltered conditions but the necessary relative proximity of farms facilitates and the restricted water exchange to the open sea generates a number of issues. These include the easy transfer between farms of parasitic sea lice, the SEPA biomass limit, planning issues and the impact of harmful algal blooms.

Locating fish farms in more exposed "offshore" locations still in coastal waters, but outside of the fjords, offers a potential solution to the problems of fjord-based working: offering the opportunity for greater distances between farms and greater dispersion of organisms (sea lice and HABs) and contaminants. Hence likely allowing the development of larger farms with improved fish heath.

However, a move "offshore" will require significant industry investment and requires science based underpinning. This project will therefore bring together a consortium of physical, environmental, biological and modelling based scientists, a major aquaculture company and stakeholders with interests in regulation and insurance of the industry to test the hypothesis of the benefits of offshore aquaculture operation.

The project will use new physical oceanographic measurements in tandem with historical and new industry collected fish health data to validate and where necessary improve biophysical models. We will establish a numerical wave model for the region. This will be combined with existing FVCOM based unstructured grid physical models that are coupled with biophysical models of sea lice dispersion, contaminant dispersion and harmful algal bloom advection and growth.

Application of these models will allow assessment of the suitability for aquaculture of more or less energetic environments.

Planned Impact

The main impact goals of this project are:

- To provide a balanced evaluation of a number of key issues affecting offshore aquaculture development prospects: improving scientific understanding of the coastal environment and fulfilling the need for scientific evidence on a topic which has been discussed for some time by the industry.
- To provide cost savings for industry, investors and isurers by enabling more informed development decisions.
- To allow regulators to develop coherent regional and national plans for development and expansion of the industry.
- To enhance community understanding of issues related to development of the aquaculture industry, allowing more informed responses to local development opportunities.

The main stakeholders that will derive benefit from this work are:
- Aquaculture site operators and investors, who will benefit from enhanced understanding of the environment in which they are planning to operate, and the risks, challenges and benefits that working in different locations may present. Marine Harvest Scotland (project partner) are directly involved in all work packages of the project, and findings will be disseminated more broadly to stakeholders via regular fact sheets, workplace seminars and workshops.
- Marine Scotland (project partner), who will gain validation for existing models allowing applcation of these models to specific industry challenges, and gain context for development of future policy on aquaculture development.
- Crown Estate Scotland (project partner), who are involved in leasing for fish farm developments, and wish to better understand the future trajectory of the industry.
- Insurers (WillisTowersWatson, project partner) will gain a firmer footing for decisions on risk levels applying to developments across the breadth of environments occupied by the industry.
- Other governmental and regulatory bodies, such as Scottish Natural Heritage and SEPA. These institutions will gain insights into the dynamics of the coastal ecosystem, the dispersion of effluents and parasites, and the limitations of current modelling techniques applied to this environment.
- The public, who will gain a clearer understanding of the benefits and costs (ecologically, financially and socially) of offshore aquaculture developments in comparison to near shore developments, via partners' web sites, fact sheets, news reports and Twitter.
Description Significant new knowledge generated regarding the impact of the offshore environment to the health and welfare of farmed fish (salmon)
We have developed a new method for identification of cortisol in mucus (in technical report)
We have developed new algorithms to analyse the data and model it
Important new research questions have opened up like what will happen in a longer time series period and what are the dynamics of the offshore farms regarding health and welfare of fish
In this study we have stablished new research networks and collaborations between the original partners and the relevant stakeholders (MOWI and Salmon Scotland)
Increased research capability generated from training delivered in specialist skills;
Expansion of offshore aquaculture should consider animal welfare and ongoing climatic changes

Wave exposure appears to act as a chronic source of stress, compounding the effects of other stressors

Coordinated, standardised data collection and sharing will improve our ability to anticipate challenges
Exploitation Route We believe this research contributes to the body of knowledge on the use and development of offshore aquaculture and to understand the impact of the environment onto the welfare of fish.
Sectors Agriculture, Food and Drink,Environment

URL https://www.sams.ac.uk/science/projects/off-aqua/
Description To understand the impact of offshore conditions to the welfare of the salmon and inform the salmon farming companies how to improve their Standard Operational Practices (SOPs) to mitigate the potential negative effect of those offshore conditiions.
Sector Agriculture, Food and Drink,Environment
Impact Types Economic

Title Method for cortisol quantification in Atlantic salmon (Salmo salar) blood plasma using liquid chromatography tandem mass spectrometry 
Description Method for cortisol quantification in Atlantic salmon (Salmo salar) blood plasma using liquid chromatography tandem mass spectrometry Blood sampling Blood sampling was performed on fish anaesthetized with MS-222. The samplings were non-lethal. A heparinised syringe was inserted into the caudal vein withdrawing up to 2 ml of blood, depending on the size of the fish. After removal of the needle, blood was dispensed into a 1mL Eppendorf and kept chilled on ice. After all the fish samples in each tank were processed the blood sample was centrifuged for 10 min at 3500xg. The plasma was transferred to a labelled cryogenic vial then frozen in dry ice. Samples were transported back to laboratory (University of Stirling) and stored at -80?C until analysis. Plasma sample preparation For plasma sample preparation, LLE (liquid-liquid phase extraction) was used before liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. Fifty microliters of an internal standard (IS) of 100ng/ml d4-cortisol in LC-MS/MS grade methanol (MeOH) was added to 100 µl of plasma in a conical glass test, followed by mixing. Then, 2ml of ethyl acetate was added to the test tube. The mixture was vortexed and left to settle for 5 mins before adding 0.5ml of 0.88% potassium chloride. After mixing the tubes were centrifuged at 1400 rpm for 5 mins. The top organic layer was then removed into a clean conical test tube and evaporated to dryness under nitrogen before being re-suspended in 45% methanol and transferred to a total recovery vial. Samples were allowed to stand for a minimum of 2 hrs in 4°C fridge before analysis. Standard curve samples were prepared by the same method: Stock solutions of cortisol at 10µg/ml was diluted in methanol to 1ng/ml, 10ng/ml, 50ng/ml, 75ng/ml and 100ng/ml, each spiked with 50 µl of IS. Liquid chromatography tandem mass spectrometry The LC-MS/MS system was a Waters Xevo TQS coupled to an Acquity I Class UPLC. Chromatographic separation was achieved on a Polaris C18-A column (3µ, 150 × 4.6 mm, Varian Inc.). The guard column was a MetaGuard Polaris C18-A (5 µ, 10 × 4.6 mm, Varian Inc.). Autosampler injections of 20 µl onto the LC-MS/MS system were made with the autosampler needle placement 3mm from the bottom of recovery vial. The mobile phase comprised a binary solvent system: MilliQ water (solvent A) and methanol (solvent B), both containing 2 mM ammonium acetate with 0.1% formic acid. The initial solvent composition was 55% A and 45% B. The mobile phase gradient pro?le involved two steps; increasing from the initial conditions to 98% B within 5 mins holding for 1 min before returning to the initial state at 7 mins, allowing 1 min for column re-equilibration. The total run time was 8 min, injection-to-injection. The ?ow rate was 0.6 ml/min and the column was maintained at 60°C. The instrument was operated in positive electrospray ionization (ESI) mode using MassLynx V4.1 Software (Waters). Electro-spay ionization and tandem mass spectrometry parameters were individually optimized for cortisol and d4 cortisol. Using the optimized transitions 363 > 121 (cortisol) and 367 > 121 (d4 cortisol), limits of detection and quanti?cation of 0.02 and 0.06 ng/ml, respectively, were achieved in standard solution. Sample inter-assay CV (n=5) = 7.1% and intra-assay average %CV (n=9) =1.1%. 
Type Of Material Technology assay or reagent 
Year Produced 2019 
Provided To Others? No  
Impact This method allows us to detect cortisol in plasma blood samples from Atlantic salmon and be used as a stress and welfare indicator with better levels of detection that the current published methods (ELISA and RIA analysis). This is the first time it has been developed for salmon and the outputs can be used as more accurate Welfare Indicator for fish farmers to assess the health and welfare of their fish in general and also the impact husbandry practices have to their health and welfare. it is also a better and more detailed method with a finer detection range and it can be used in fish stress research for example as a better tool to get more accurate results. 
Description Off-Aqua MOWI 
Organisation Marine Harvest
Country Norway 
Sector Private 
PI Contribution The project seeks to better understand the proc and cons of developing offshore finfish aquaculture in UK waters. As such the results of the project will be directly relevant to MOWI in their business planning
Collaborator Contribution MOWI provides the research team with access to sampling sites at their fish farms, logistical support and access to data
Impact Access to fish farm sites has been fundamental to data collection by the project partners
Start Year 2019
Description ARCH-UK Webinar Series: The Offshore Aquaculture Project 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact This was a webinar hosted by ARCH UK in which several members of the Off Aqua BBSRC project gave a webinar. The intention was the present an overview of our project and findings to the scientific community. Many people attended and they shared their opinions, doubts and words of encouragement.
Year(s) Of Engagement Activity 2020
URL https://www.aquaculturehub-uk.com/past-events/offaqua
Description Evaluating the Environmental Conditions Required for the Development of Offshore Aquaculture: Impact on Farmed Atlantic Salmon Health and Welfare 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact This was poster presented at the Aquaculture Europe in 2019.
The intended purpose was to disseminate our results that were preliminary but in a field as new and active as offshore aquacultur, they are still important and could reach many people. Our poster sparked discussion with other researchers, with whom we shared findings and hypothesis, and this was important to shape future experiments.
Year(s) Of Engagement Activity 2019
URL https://www.researchgate.net/publication/336579598_Evaluating_the_Environmental_Conditions_Required_...
Description International Conference 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Oral presentation on the International European Aquaculture Society conference (EAS) in Cork from 12th to 15th April 2021. There was a dedicated session on Off shore Aquaculture and most of our work in this project was presented. There was a lot of interest and questions arise both from academics and industry participants.
Year(s) Of Engagement Activity 2021
URL https://aquaeas.org/_pdf/AE2020BluePages.pdf
Description International conference: Aquaculture Europe 2022 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Oral presentation at the Aquaculture Europe conference which sparked discussion and emails from interested researchers and practitioners. The talk, entitled "Environmental drivers of fish mortality along an inshore-offshore gradient in Scotland", was intended to disseminate findings regarding the potential for expansion of fish farm aquaculture to more wave exposed locations. There were specific requests for additional information from conference attendees from the Faroe Islands.
Year(s) Of Engagement Activity 2022
URL https://eposters.blob.core.windows.net/eas-eposters/AE2022AbstractBook.pdf
Description Sh ould we go offshore? A case study of offshore Atlantic salmon aquaculture in farms off the west coast of Scotland 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact At this point, this is an abstract that was accepted as a talk at the Aquaculture Europe 2020 (Held in April 2021).
While in Aquaculture Europe 2019 we presented preliminary results, in this international conference we will present our final results.
Year(s) Of Engagement Activity 2021