SBAG Scottish Beaver Advisory Group Meeting - Translocation workshop using the Ness catchment as an example - 27 February 2025

Welcome and Introductions

The chair opened the meeting by thanking attendees for attending both in-person and online.  As per the paper circulated in advance of the meeting, the aim of the workshop was to have a strategic exploration of beaver translocation using a specific geography as an aide to furthering understanding/ refining the processes in place. The Ness catchment had been selected as an example. Relevant stakeholders from the region were invited to participate, in addition to the core membership of SBA.

Overview of the SEA for the Ness Catchment

NatureScot gave the group an overview of the screening report for the Rivers Ness and Lochy catchments published in March 2024. SEA provides a structured approach to considering effects on the environment. A screening approach had been taken given the existing Environmental Reports for other areas. The screening report sought to determine if there are likely to be new, or effects at a scale not previously considered in these catchments. It was noted that SEA focuses on environmental effects rather than providing a socio-economic assessment and that as yet methods do not exist that would allow all benefits and costs to be quantified. One approach to better quantifying the extent of potential benefit and conflicts in a geography was discussed, as developed in Switzerland (Dennis et al. 2024, Global Ecology and Conservation 56 (2024) e03304). A graphic was shared illustrating how the likely areas of benefit and conflict (from beaver dams) may be expected to vary within a catchment based on slope and topography. It was suggested this model is likely to also have relevance in Scotland. It was highlighted Switzerland does not have Atlantic salmon and hence there may be more conflicts in the smaller streams suitable for damming than in Scotland. This was acknowledged. The reason for sharing the model was to highlight the potential for GIS mapping/modelling to better quantify risks and benefits/ spatially if not economically recognising some aspects may differ in a Scottish context. 

It was suggested beaver effects will be constrained in these catchments by topography and woodland cover, and potentially hydro dams. Some of the main issues in the catchment were considered to be:

• Oceanic or rainforest character of the woodlands and associated interests
• Fish and fisheries interest
• Farming and forestry (recognising the importance to individual farm businesses of land that is classed as lower Capability for Agriculture).
• Connectivity to other parts of the west coast via sea lochs
• Infrastructure -west coast railway line and the Caledonian canal.

There was some discussion of how any burrowing into canal embankments can be identified and monitored. Scottish Canals already have a schedule of inspection (leakage inspectors) but further engagement with Scottish Canals would be necessary to assess the risks (existing bank material/ protection/ weirs sluices, trees that could be felled into the canal) and what monitoring and mitigation would be appropriate if beavers were present. There may be a possibility of training courses for leakage inspectors to understand and identify beaver activity. There was a wider discussion of what would be recognised as ‘low conflict’ areas, with different interests potentially being affected in different areas, whether agricultural, fisheries, lichens etc. 

Projection of Population Spread

NatureScot shared some outputs of simulations for the Ness/ Lochy catchments from the Beaver Population Simulation App as recently demonstrated to SBAG by Aileen Mill from the University of Newcastle. The model is a spatially explicit individual based population model. The model predicts population growth based on beaver life history parameters (a range) within a landscape derived from habitat mapping. Habitats are classified as ‘suitable for establishing a territory’, ‘suitable for dispersal’ or ‘unsuitable’. Hence it is a simplification of reality and seeks to provide predictions on this basis for translocation scenarios. Several scenarios were illustrated from a small number of distant release sites, up to 10 families into suitable habitats.  All model runs suggested the number of beaver territories would increase; with a plateau around 40 territories. Further exploration would be needed to determine what factors underlie this levelling of population growth. The simulations suggest the area can have a viable beaver population (indeed there is historical evidence of a beaver population in this area), however, the number and connectivity of release sites are likely to be important for population viability. It was noted that given discussions of the importance of topography, the model is 2D and does not take account of the gradient of the catchment as a predictor of suitability. Any additional comments on the use of the model can be directed through Kieren. 

AP 1 NatureScot to circulate details of the population model and how it operates/ assumptions.

Potential Benefits and Challenges from Beaver Presence - All 

Some of the benefits challenges raised by the group in relation to the Ness catchment included:

• Concerns for impacts on bryophytes and lichens e.g. Urquhart Bay Woods, Abriachan, Foyers and Ness Woods. But concerns are not limited to designated sites.  The greatest lichen/bryophyte interest relates to humidity which occurs in the riparian zone, that is most likely to be impacted by beaver. Also concerns about the current knowledge base, e.g. the Cairngorms NP are looking to do some further survey/ gap analysis. There were some concerns raised around the mitigation options address impacts on lichens and bryophytes.  
• There was a general concern about deer densities limiting regeneration and beavers being an additional factor. Potential for beavers to impact on woodland creation schemes and arrangements for repayment of grants. It was noted Scottish Ministers have asked Scottish Forestry to review policies on grants but are seeking to support both beaver and woodland expansion policy aims.
• The River Ness has a good early spring salmon population and areas prone to damming by beavers may conflict with salmon spawning. Discussion on sharing data on spawning sites so that they can be overlaid with dam capacity modelling. This would be useful information to help inform the relative risk of conflicts. Discussion of the costs/resources that may be required to mitigate these impacts at scale.
• Potential for benefit for flood mitigation e.g. around Drumnadrochit.

Wider discussion points

• To consider how we balance wider benefits to ecosystems and particular species conflicts.
• Should the focus be on risk and manageability? Identifying the key sensitivities, knowledge gaps and mitigation options, and prioritising areas where the level of risk is with an acceptable range
• Seek conversations regarding species conflicts and mitigation options in advance rather than after licences have been issued.

AP 2 NDSFB to share data on spawning sites with NatureScot to carry out a spatial analysis of potential conflict between spawning sites and any predicted downstream capacity for beaver damming.

Funding Possibilities for Engagement and Mitigation – All

The potential for community grants e.g. from renewable energies and ecotourism to help fund engagement and enhanced mitigation measures was discussed. Pumped hydro was discussed both as a source for funding and the environmental consequences of these projects were also raised with concern from both a fish and beaver perspective (cumulative effects on fluctuations in water levels).  The benefit of developing strategic proposals from a beaver population and also from a sharing of resources perspective was again recognised.

The meeting was closed thanking participants for their contributions. It is hoped that some of the discussion can inform future thinking/ the development of proposals for new catchments.