Wild Salmon Strategy Science and Evidence Board minutes: November 2023

Attendees and apologies

• John Armstrong, Marine Directorate (Chair)
• Stuart Middlemas, Marine Directorate
• Lyndsay Christie, Marine Directorate 
• Alex Kinninmonth, Marine Directorate 
• Nora Hanson, Marine Directorate
• Alan Wells, Fisheries Management Scotland 
• Colin Bean, NatureScot 
• Peter Pollard, Scotish Environment Protection Agency 
• Melanie Smith, Atlantic Salmon Trust
• Lorraine Hawkins, Dee District Salmon Fishery Board
• David Summers, Tay District Salmon Fishery Board
• James Hunt, Tweed Foundation
• Chris Todd, St. Andrews University 

Items and actions

Welcome 

• JA welcomed everyone to the meeting
• Nora was welcomed to the board, Nora and Stuart will act as deputy chairs and can cover for chair if needed

Minutes of last meeting

• JH affiliation corrected to Tweed Foundation
• no other comments, minutes agreed by board members

Discussion on stocking

The focus of the meeting followed on from the previous meeting to appraise different methods of stocking.

A document was circulated in advance of the meeting setting out the North Atlantic Salmon Conservation Organisation (NASCO) position on different stocking methods and other relevant research. This formed the basis of discussions.

The stocking methods being considered are for salmon populations that are rapidly declining. The advice for stocking when populations are stable is well established and that is not being reconsidered. 

Need to be clear whether the approaches being discussed are for conservation of the species or conservation of the fishery. 

Smolt to adult supplementation (SAS)

Discussion on the use of smolt to adult supplementation including:

• work that has been done in the Bay of Fundy and how that is applicable to Scotland
• SAS would only be suitable as a short term mitigation while other pressures are addressed
• the use of smolts vs. parr – parr may be more hardy to being taken into captivity

Stocking eggs

Discussion on the use of stocking eggs including:

• need to understand if there is a difference in egg quality and if can egg quality be improved artificially

Fry redistribution 

Discussion on the use of fry redistribution including:

• principle of fry redistribution is to overcome density dependence, however there are issues associated with this
• potential issues include fish being vulnerable during and after redistribution, disruption of family interactions, reduced competition leading to less variation, evidence of homing in redistributed fish
• general agreement that fry redistribution should not be recommended

Kelt reconditioning

Discussion on the use of kelt reconditioning including:

• kelts have already undergone selection and survived in the marine habitat
• few kelts survive in the wild so reconditioning is low risk
• need to consider quality of offspring related to numbers of spawning events

General considerations

• in all cases when stocking is being considered because of low populations it is important to understand what habitat is limiting production
• improvements should be made to habitat in the first instance before stocking
• agreement there may be further work and evidence gaps to fully understand limiting habitat and how it can be addressed
• conservation translocation guidelines state the habitat to which someone intents to translocate must be suitable for the species being moved
• the economics and costs involved with different stocking methods also need to be considered by fishery managers
• with both kelt reconditions and SAS there may be a risk of disease. The risk of disease differs between freshwater and saltwater
• if the chosen method of stocking is creating a sub population of domesticated fish an exit strategy is need
• the goal of the stocking activity needs to be clear

Conclusions

Following discussions about the different methods of stocking the following summary points were agreed:

• smolt to adult supplementation may be a viable option as taking wild smolts provides maximum diversity for minimal risk
• the methods of stocking discussed should only be considered in extreme situations and this still needs to be defined 

Next steps

• JA to draft a summary of evidence of the risks and benefits of the different stocking methods discussed
• the summary will be circulated to board members for comment

Any other business

• AW raised concerns about the sea lice threshold being proposed by SEPA for the sea lice risk assessment framework. To be discussed further by email
• DS raised concerns about blue fin tuna fishing using longlines and if there is a potential risk for salmon
• The International Union for Conservation of Nature (IUCN) global assessment for Atlantic salmon will be updated on 7 December, expected to move from least concern to near threatened