Beavers in Scotland - Environmental Report Addendum 2022

Introduction

Beaver Translocation programme

In November 2021 it was announced that Scottish Government would actively support the expansion of the Eurasian beaver Castor fiber population into new areas of Scotland to establish the species in areas outside their current range. Beaver translocation is viewed as an important tool in nature restoration and climate change mitigation, with this change in policy enabling these benefits to be realised across other suitable parts of Scotland. Translocations also present the opportunity to reduce negative impacts from beaver activity in conflict areas. Being able to move beavers to new areas provides greater opportunities to trap and translocate rather than manage beavers in conflict sites.

As licensing authority NatureScot will have a role in licensing releases to new catchments. By releasing beavers into new catchments, they will have the potential to spread throughout the catchments over time. Hence the assessment of risks and benefits will need to be at a whole or sub-catchment scale, rather than being specific to the land holding where they are released. In supporting the implementation of this policy NatureScot are in effect developing a forward programme for beaver translocations to other suitable catchments within Scotland. This programme requires the assessment of environmental effects at an appropriate level.

Background

This announcement presents a significant shift from the policy that has been in effect since it was decided that beavers could remain in Tayside and Knapdale in November 2016. The Environmental Report that accompanied this decision was published in 2017 and explored alternative scenarios for beavers in Scotland which included;

• Scenario 1 - full removal of beavers from the wild in Scotland

• Scenario 2 - restricted range. Allowing beavers to expand from their current range, but specific catchments would be managed to keep them free from beavers.

• Scenario 3 - widespread re-colonisation. The beaver population would be allowed to expand to its natural limits. Eventually this could include further releases outside the two current population areas.

• Scenario 4 - accelerated widespread re-colonisation. Proposals for new releases could be considered immediately.

The policy agreed by Scottish Ministers in 2016 draws from both scenarios 2 and 3 in the report and outlined that:

• Beaver populations in Argyll and Tayside can remain;
• The species will receive legal protection, in accordance with the EU Habitats Directive;
• Beavers will be allowed to expand their range naturally;
• Beavers should be actively managed to minimise adverse impacts on farmers and other land owners;
• It will remain an offence for beavers to be released without a licence, punishable by up to 2 years imprisonment and an unlimited fine.

The 2017 ER concluded:

‘The decision acknowledges the range of benefits of beavers being present in Scotland but also the importance of demonstrating how the reintroduction can best be actively managed to minimise adverse impacts on land managers in Tayside and Argyll before considering further reintroductions elsewhere in Scotland’.

The Eurasian beaver became a European Protected Species (EPS) in May 2019.

Update to key changes since the 2017 Enviromental Report

There have been five key changes that underlie the policy change since the ER was published in 2017. The policy context has changed considerably with regard to nature restoration and the role of nature based solutions; we have learned more about the role that beavers can play in natural processes, we know more about the status of the beaver population, and we have developed management approaches through the Beaver Management Framework. Stakeholders have together produced Scotland’s Beaver Strategy in 2022 which provides a vision for beaver restoration in Scotland, and identifies actions to be taken forward.

Policy context - nature and climate crises

Scotland is in a climate and nature emergency, often described as ‘twin’ crises due to the extent they are interlinked. Scottish Government declared the Climate Crisis in April 2019 and set out our ambition to take strong action to tackle biodiversity loss in December 2020, with a commitment to publish a new Biodiversity Strategy by the end of 2022 and delivery plan by summer 2023. The consultation on the new Scottish Biodiversity Strategy has been launched.

Scottish Government’s Programme for Government in 2021-22 is entitled ‘A Fairer, Greener Scotland’ and puts climate change and nature restoration at the forefront of the Programme and cuts across government departments. This is also the first PFG delivered in the context of the new Scottish Government and Scottish Green Party Parliamentary Group Agreement. 

Hence since the ER was published in 2017 there has been much greater prominence given to the need for transformational changes to deliver on both crises, much greater focus and political backing for nature restoration and the use of nature-based solutions as a means of delivering these changes.

Scotland's Beaver Strategy

Scotland’s Beaver Strategy has recently been published and aims to provide a forward looking vision for beaver restoration in Scotland. The vision is as follows:

The strategy was co-produced with a wider range of stakeholders and independently facilitated by the IUCN SSC Conservation Planning Specialist Group. The Strategy is not spatially explicit in that it does not highlight where the greatest opportunities for beaver restoration are likely to arise nor where there are likely to be potential conflicts, but instead sets out a series of goals, objectives and actions to ensure beaver restoration in Scotland is ambitious, yet fair and transparent.

The main field-based activities of the Scottish Beaver Trial (SBT) at Knapdale ended in 2014, and were reported on in the 2015 ‘Beavers in Scotland’ to Scottish Government. The project had been designed as a time-limited, scientifically monitored trial within a naturally contained landscape but, following the ministerial announcement that the beavers could remain at the site, attention switched to examining the longer-term viability of the population.  In 2017 a survey established that a minimum of ten individuals were present, with territories encompassing several water bodies around the site. There then followed the ‘Scottish Beavers’ reinforcement project between 2017-2020 managed by the Royal Zoological Society of Scotland and the Scottish Wildlife Trust, in collaboration with Forestry and Land Scotland and NatureScot. During this period a total of 21 animals were released into Knapdale, by the end of which it was clear that all suitable release sites were occupied, and at least three territories established encompassing most of the suitable standing water bodies. The fate of some animals is unknown, and no evidence has been found of colonisation outwith Knapdale Forest. The Scottish Beavers Report put forward a number of recommendations for the future management of the population, including proposals for strategic releases of animals into the Loch Awe area to provide a link with the expanding Tayside population thereby increasing the likelihood of longer-term viability.

A complete resurvey of the Tay and Forth catchment was carried out in the winter of 2020/21. This was brought forward from the scheduled survey 2021 to provide up to date information on population spread and the implications of management under licence since beavers became EPS. The 2020/21 survey found the number of active territories had more than doubled from that found in 2017/18 with evidence of 251 active territories compared with 114 in 2017/18 and 38/39 in 2012. Overall the population had expanded annually by between 17% and 30%, with the upper estimate considered more likely and is greater the increase of 8-24% between 2012 and 2017/18. The findings suggest that the population is in a phase of rapid expansion.  The 2020/21 figure of 251 territories roughly equates to 954 individuals (range 602 to 1381). By summer 2022 there will have been two further years of population growth. The 10km buffer zone established in the 2017 ER was intended to encompass the anticipated spread over a ten year period (to 2027). Figure 1 illustrates that within 5 years the population had expanded outwith the buffer zone, particularly on the Forth and into the Trossachs. The spread to the north appears to have been limited in the Angus Glens and to the north by man-made barriers such as Pitlochry dam.

Figure 1: 2017 Beavers in Scotland ER buffer area for Tayside and 2020/21 distribution of territories in the Forth and Tay catchments

The 2017 ER referred to the need for active genetic management of the Scottish beaver population to avoid inbreeding depression. We now know more about make-up of British populations with Campbell-Palmer et al. 2020 reporting the genetic composition of 34 animals from Tayside (20112-2014) and nine from the River Otter (Devon) population. Thirty three of the Tayside animals were assigned to Barvarian origin and one to Lithuania/Poland. The genetic diversity of the Tayside population was similar to the source population, although showed a high degree of relatedness. The authors conclude ‘The Tayside beavers could provide a reasonable source of founding individuals for any future reintroduction of this species, though genetic management to encourage diversity is recommended’. Consideration will need to be given to the size and origin of new founder populations to maximise diversity/ linkage to existing populations.

Campbell-Palmer et al. 2020 also published the findings of health screening of beavers from Tayside (56 from live-trapping in 2012-204 and 2017-2019) and 25 from post mortem) and Knapdale (9 live trapped and 7 post mortem).  The authors concluded none of the beavers tested harboured any non-native disease or parasites of concern and demonstrated remarkably low levels of any disease or parasite exposure.

Over the last three years of EPS nearly 80 beavers have been trapped on Tayside and translocated to other licenced projects either in Scotland or in England and Wales. This has brought experience of animal handling and welfare as well as contributing to our knowledge on disease and genetics.

Operation of Beaver Management Framework

In the lead up to beavers becoming EPS on 1^st May 2019, NatureScot worked with members of the Scottish Beaver Forum whose representatives include farming, fisheries, forestry and conservation interests to develop a Beaver Management Framework. The Beaver Management Framework (BMF) aimed to balance the desire to allow the beaver population to continue to expand their range naturally whilst allowing significant detrimental impacts of beavers on particular interests to be managed. This framework includes the Scottish Beaver Mitigation Scheme, the species licensing regime, the policy on translocations, the research and monitoring strategy and further work to increase our understanding of the benefits and ecosystem services provided by beavers. The guidance that underpins the BMF is currently under review to reflect the recent policy changes and to ensure it continues to be fit for purpose.

Reports have been produced for each year of beaver licensing since they became EPS based on information from licence returns (Table 2 summarises they key findings).

² SNH Beaver Licensing summary - 1st May to 31st December 2019, Scottish Natural Heritage
  Beaver Management Report for 2020 | NatureScot
  Summary of beaver populations and licence returns covering the period 1st January to 31st December 2021

As highlighted in Table 2, 79 beavers have been trapped and translocated from Tayside in the last three years. The trend has been for an increase in the uptake of the use of trapping as it has been shown to be effective and a desire to see a reduction in the use of lethal control. NatureScot would like to see a further increase in the proportion of beavers that are having to be removed being trapped and used to source translocation projects. To date the beavers from Tayside have largely gone to Knapdale and licenced projects in England and Wales. Wild releases to Argaty to reinforce the population already present on the Forth were authorised in 2021.

In the 2020 report we assessed the impact of licensed removals (both lethal control and trapping from 2019 and 2020) on the conservation status of the species and concluded that it continues to improve. The Beaver Management Framework, whilst still in its early years and continuing to be adapted is considered to be providing the necessary tools to enable land managers to address serious land use conflicts via a combination of mitigation and species licensing whilst allowing the natural range and population to continue to expand. Species licences have been required for the purpose of public health and safety requiring the installation of mitigation on some infrastructure (railway lines, cycle paths), for the protection of forestry (forest roads), but predominantly for the purpose of preventing serious agricultural damage, where there is no satisfactory alternative in the form of mitigation. Agricultural impacts in parts of the river Isla, river Tay and Earn sub-catchments continue to be those situations where mitigation has proved to be most challenging because of the topography, immediate adjacency of land use and widespread beaver presence. Whilst lethal control and relocation presents a last resort option for reducing impacts, clearly it would be desirable to avoid releasing beavers into new catchments where they would cause conflicts to the same degree as they have in these catchments. From the spatial analysis we have carried out (see section 3) Tayside is predicted to have the largest extent of overlap (or adjacent to) between potential beaver habitat land with a high capability for agriculture. However, there may be few catchments where there would not be any conflicts that would require any use of species licencing.

The Scottish Beaver Mitigation Scheme has been in operation since 2019 and informally prior to that since 2008. The scheme is available to land and fisheries managers to request free advice and practical assistance to help mitigate beaver impacts. The majority of request for advice and assistance have been in relation to impacts on trees and to agricultural impacts. From experience since 2019, we would note that whilst straightforward mitigation can resolve conflicts in some situations, it is not possible to resolve all, particularly agricultural conflicts through established mitigation. NatureScot are seeking to trial some of the techniques used elsewhere in mainland Europe to ‘make space for water’ (and beavers). Such opportunities are expected to bring wider benefits in terms of biodiversity, flood attenuation, water quality and reducing soil erosion. However, there are currently circumstances where conflicts cannot readily be resolved and it has been necessary to issue protected species licences to remove beaver dams, exclude beavers or as a last resort, authorise beaver removal.

NatureScot produced a report on Beaver Management in 2021 which details the work being progressed by the Scottish Beaver Mitigation Scheme. To date the range of work being carried out falls into three main categories: tree protection, flow devices in dams, and beaver exclusion. In the last year this has been complemented by the use of water levels sensors to alert land managers to an increase in water levels to indicate the presence of a dam, allowing a swift response and a reduction in the amount of manual monitoring for dams. There is currently a Civ-Tech challenge project looking at the use of novel technology to help detect and assess the risk associated with beaver burrows.

Table 3: Commentary on frequency of instances where mitigation and management actions outlined in NatureScot Guidance have been employed and on their effectiveness.

Table 3a: Mitigation techniques for dam building activity

3b - Techniques used to manage beaver burrowing and digging activity

3c - Techniques used to manage beaver foraging activity

3d - Actions to mitigate effects on human health and INNS spread.

Research has continued to examine the effects and potential effects of beaver restoration in a UK context. Several reports have been produced in 2020 and 2021 that highlight the many potential roles that beaver may have in many ecological and physical processes.

A recent independent evidence review of the role of beavers in modifying physical processes, and the potential benefits they may bring for the provision of ecosystem services was published by CREW (2021) with a policy note summary. It concludes that beavers are likely to have an overall positive impact, with key findings and gaps in our knowledge included in Figure 2.

Figure 2 - Key findings of CREW report on physical processes and ecosystem services

• Most of the evidence of beaver activity effects on the physical functioning of streams and rivers points to positive contributions to local ecosystem services. There is strong evidence that beaver dam-building results in wetland creation and the trapping of suspended sediment, nutrients and contaminants. In addition, high flows are typically lowered and delayed, while recharge, water storage and residence times increase. Beaver activity can therefore contribute to water supply and purification, the moderation of extreme events, nutrient cycling and river restoration.
• Enabling positive contributions to ecosystem services may also involve compromises and care must be taken to manage any dis-benefits. Beaver activity effects may include the loss of land because of habitat creation and increased flooding behind dams. While flooding increases in the area behind beaver dams, beaver activity contributes to small-scale downstream decreases and delays in the flood peak. The relative effects will therefore depend on the location in relation to the beaver activity, as well as the surrounding land use (e.g., in most cases any flooding in built-up areas is likely to have larger socio-economic effects than the flooding of forested areas).
• Depending on site characteristics, other effects that could be considered as dis-benefits include interruptions to fish passage because of decreased hydrological connectivity within a river network. In addition, average water temperature typically increases locally, but beaver activity is also associated with decreases in the maximum temperature. Changes in water temperature can have implications for instream ecology and private/industry water users.
• For carbon storage, beaver activity is simultaneously paired with increased carbon storage and increased methane and carbon dioxide emissions; the offsets between these two effects are highly variable and less known.
• Dam-breaching - part of the evolution of beaver systems - can have detrimental effects. These include exacerbating flood events and the release of sediment and contaminants that were being retained by a dam. The significance of these effects will depend on the timing and extent of breaching.
  
  Remaining questions (future research needs)
• How do beaver activity effects scale to rivers that drain larger catchment areas? Most evidence has been recorded at the local scale, i.e., up to about 1 km²; policy and practice for ecosystem services would benefit from evidence at larger scales.
• What are the effects of beaver activity on the full range of stream discharge? There is less evidence of the effects of beaver activity on low flows and storage-discharge relationships.
• What is the net effect of beaver activity on greenhouse gas emissions and carbon sequestration and so the carbon budget, and what controls the balance locally?
• What are the site-specific controls on the magnitude of beaver effects? Some effects depend strongly on local beaver activity and landscape characteristics. This poses problems for the transferability of effects to other sites, especially with different characteristics. The evidence base lacks studies from Scotland and the UK, non-forested environments, and at larger scales.

Natural England published a review of evidence in November 2020 to inform thinking around beaver reintroductions in England drawing on research from work that has been published since the Beavers in Scotland report was published; which synthesised evidence up to 2015. This is a very useful reference summarising what evidence has been gathered since the 2017 ER and hence we have included the key findings as Annex 1 to this addendum. The review concludes there is little new evidence on beaver interactions with bryophytes, lichens, fungi, vascular plants, reptiles nor on fisheries and forestry interests. In general the evidence supports the Beavers in Scotland report highlighting that:

• Beaver activity can enhance the natural functions of river system, restore wetlands and promote biodiversity, including of amphibians and birds.
• Beavers create more heterogeneous and diverse riparian woodlands both across the landscape and through time.
• The evidence around the impacts of beavers on fish populations presents a complex and often contradictory picture. However, considered at a suitably broad temporal and spatial (catchment) scale, the increase in habitat diversity and dynamism brought about by beavers is likely to result in more diverse fish populations with greater ability to sustain themselves, particularly in the face of climate change.
• The evidence also points to differing effects on different invertebrate groups at different times and locations. Impacts on freshwater pearl mussels and white-clawed crayfish are expected to be complex, with both positive and negative impacts at differing times which may require management where populations are vulnerable.
• Experience of conflicts in an agricultural setting highlight that impacts tend to be concentrated in more intensively managed arable land on floodplains; and note that those benefitting from beaver activity (largely from water management) may not be the same as those who bear the costs. 
• The potential for negative and positive effects on infrastructure on floodplains was noted, recommending approaches are developed for management and that planning seeks to make space for water with a view to minimising conflicts.
• The report highlights uncertainty around what role habitat modification as a result of beaver activity may have in the dynamics of water vole and non-native American mink.
• Disease risk analyses have been advanced and are recommended be involved in any reintroduction programme.

The review concludes that ‘If managed appropriately, the quantifiable benefits of beaver reintroduction in relation to natural capital and societal benefits could be much greater than the financial costs incurred’. Societal challenges stem from conflicts over land use and the perceived risks to salmonid and other migratory fish populations. In terms of benefits it is noted ‘Beaver activity is not a substitute for tackling impacts on catchments (such as pollution, over-abstraction, and artificially exacerbated flood risk) at source, but can enhance water-related ecosystem services, especially where suitable measures have already been taken to restore natural ecosystem function to the headwater areas of catchments’. It is apparent that scale is important when looking at the evidence of impacts on different species groups and at a local level there will be winners and losers, but when impacts are considered at a landscape scale with temporal and spatial dynamism, the balance is expected to be beneficial.

In addition to the reports identified above, a number of relevant scientific papers have also been published since 2017, including studies carried out in Scotland and elsewhere in Britain.  These have added to our knowledge of beavers and their interactions with the environment, and include studies on beaver-trout interactions at a Scottish site (Needham et al. 2021), and beaver interactions with wetland species and their role in habitat restoration (Law et al. 2017; Wilson et al. 2020).

Monitoring of designated interest since 2017

We have reviewed which Natura sites within the two 2017 HRA detailed zones of appraisal have since had a Site Condition Monitoring Assessment carried out. Only six features have formally reported. None of the reports make reference to beavers in the assessment. Beavers are not listed as a pressure on any Site Condition Monitoring assessment to date. There is mention of beaver in a Management Note for Dochart Meadows SSSI which refers to beavers as potentially having a positive effect on the grassland and fen interests. The only other mention of beavers is a Site Management Note for Dunkeld - Blairgowrie Lochs SAC - Slender naiad (Najas flexilis) which notes that beaver presence at Lochs Craiglush, Lowes and Butterstone, which could alter the hydrology of the lochs in the future.

During the Scottish Beavers reinforcement project at Knapdale, Forestry and Land Scotland (FLS) commissioned an assessment of lichen interests associated with the ‘Western Acidic Oak Woodland’ qualifying features of the SAC, specifically in the area around Loch Barnluasgan which the beavers colonised during this period. This survey was used to inform the protection of certain trees (primarily hazel) where lichen species of particular conservation interest were identified. FLS have reported that the only trees to have been protected since this assessment as a precautionary measure have been some medium to large sized goat willows, which had a particularly rare lichen on them.

Cycle 3 of Site Condition monitoring (2014 – 2020) used a statistical method of randomised site selection. Cycle 4 (2020 – 2030), however, is operating using a risk-based method, where those sites in unfavourable condition or where negative pressures are suspected/highly likely are prioritised for assessment. This has meant that possibly fewer interests have been re-assessed than may have been anticipated in 2017.  Moving to our new three tier method has also reduced the proportion of assessments which are full SCM (tier 2) with more sites being subject to a site check (tier 1). However, any new pressures identified by the more light touch and opportunistic site check methods, will trigger a full follow up Site Condition Monitoring assessment. Covid lockdowns and staff absences were also a significant limitation to site visits and carrying out assessments over this period. The current Site Condition Monitoring programme is a 10 year cycle, so the features not covered in 2022 will be incorporated in to the programme for the coming years.

From a beaver casework perspective the Beaver Team at NatureScot are aware of discussions in relation to five designated sites.

• Loch of Kinnordy SSSI/SPA - with regard to a dam at the outflow potentially affecting water and nutrient levels. A flow device has been installed and RSPB Scotland have a management plan in place.
• Bog wood and meadow SSSI – damming had elevated water levels which required the installation of a flow device and culvert protection on the adjacent railway line. Water level monitoring is to be installed on the SSSI to monitor impacts on the fen meadow feature.
• River Dochart Meadows – as referred to above beaver tree felling and canal building could lead to water egress onto the site and change the habitats, but specialist advice considers this likely to promote species richness of the lowland neutral grassland/fen meadow.
• Beaver presence has recently been noted at Loch Mahaick SSSI during Site Condition Monitoring with impacts on several trees noted.
• Knapdale lichen interests as detailed above.

SEA Methodology

Strategic Environmental Assessment

Strategic Environmental Assessment (SEA) is required where it is considered that there will be likely significant environmental effects arising from the plan or policy and additionally where there are likely significant effects on the interests of European designated sites. In this case we are regarding the programme of beaver restoration in new catchments in Scotland as a policy or programme that requires to be assessed. The approach to producing this environmental report as an addendum to the 2017 ER has been discussed with the other consultation authorities who have indicated this approach is appropriate because the receptors and types of impacts are likely to very similar to those assessed in 2017.

We plan to allow a six week consultation period on this Environmental Report from 10th October to 18^th November 2022. The documents are available to view as printed versions at NatureScot, Great Glen House, Leachkin Road, Inverness, IV3 8NW. Responses to the consultation should be sent using the online form, or in hard copy to Jenny Bryce, Wildlife Management Team, NatureScot, Great Glen House, Leachkin Road, Inverness, IV3 8NW. There is also an email address for correspondence [email protected]

This Addendum aims to provide a national overview of potential beaver impacts of beaver restoration across Scotland; identifying which catchments are likely to present the best opportunities for beaver restoration in terms of net benefits and lowest conflicts. We propose to carry out an assessment of the environmental effect of beaver releases in individual catchments as a stand-alone summary for each catchment that is to be assessed. In this first tranche we include assessments for the River Leven (Loch Lomond) and adjacent Forth catchment noting that parts of the Forth were included in the 2017 Tayside Detailed Zone of Appraisal.

We plan to produce stand-alone assessments for further catchments (as they are prioritised from our spatial analysis and from interest in beaver translocations) in the coming years and will also publish a summary and consult on these assessments. We anticipate that as more catchments are considered some of the effects will be similar and hence the approach to assessing effects may be streamlined to where it will add most value i.e. focusing on effects that are likely to be catchment specific.

In the addendum we are building on the Strategic Environmental Assessment that was carried out in 2017. The assessment that was carried out made a systematic assessment of the significance of likely beaver effects on biodiversity, water, population and human health, cultural heritage and material assets. Impacts on landscape, climatic factors and air were considered to be outwith scope and soils were considered in terms of the effects on water resources and biodiversity. The assessment of biodiversity takes a broader view of impacts on species than the Habitats Regulation Assessment that accompanies it, which focuses on Natura interests.

In scoping the potential impacts on new catchments we have only included mainland Scotland. It is possible that beavers were historically present on inshore islands, but it is unlikely that they reached many of the outlying islands. Hence although beaver restoration could be considered on the islands, for now it is assumed that the focus and greatest restoration potential lies in mainland catchments.

The SEA objectives are largely unchanged with the scope being mainland Scotland rather than specific to the two catchments considered in the 2017 report, but we might add more explicitly:

• To utilise the potential of beaver restoration as a nature-based solution delivering a range of ecosystem services.

Proposed approach to the SEA Addendum and what we are resting on from the previous ER

The 2017 ER was underpinned by the Beavers in Scotland report (2015), which was a distillation of a considerable body of research on the interactions beavers may have on the natural and human environments. The 2017 ER provided a detailed assessment of the range of receptors, identifying the types of impacts that would be caused by beavers and systematically looking at whether these could be positive or negative, where there was evidence to support this. Rather than seek to reproduce this information here, in Table 4 we have summarised the main conclusions, with a view to focusing on the impacts that are most likely to be significant (in bold) or for which there is currently not established mitigation.

The assessment of LSE was then followed by an ‘Appropriate Assessment’ for a subset of all sites that were within the ‘zone of detailed appraisal’ in Tayside and Knapdale where these qualifying interests listed in Table 5 are found.In 2017 the Appropriate Assessments were carried out by feature type and by site. In all cases the conclusions was either that there was no adverse effect on site integrity or that certain monitoring, mitigation and management planning actions would be necessary to ensure this was the case (Annex G). We can summarise these management actions by feature type (Table 6).

An appropriate assessment will be produced by NatureScot for new catchments under consideration.

Other regulatory requirements

As per the 2017 ER - in addition to the requirements of the Habitats Directive and Habitats Regulations detailed in section 2.2 above, the Wildlife and Countryside Act 1981,(as amended) requires any release of beavers into the wild to require a non-native species licence as beavers are classed as a former native species. The Nature Conservation (Scotland) Act 2004 may trigger the need for consent from NatureScot if beavers are released onto a SSSI which then subsequently have the potential to affect other notified features. The Salmon and Freshwater Fisheries (Consolidation) (Scotland) Act 2003 may require consultation with relevant District Salmon Fisheries Boards, fishery owners and SEPA where riverine habitat is likely to be modified by beaver activity.

National Overview 2022

Quantification of potential environmental interactions

We have identified datasets that represent important interests that may impacted by beavers as informed by the 2017 Environmental Report. We have used these data to carry out a quantitative analysis of potential interactions with beavers across all 138 catchments in mainland Scotland. A key driver for carrying out the analysis in this way has been the desire to identify catchments where beavers are likely to provide the greatest benefits in terms of the ecosystem services they provide and at the same time minimise the level of conflicts. However, because there are a large number of issues to consider, that their importance varies, and that many issues cannot be readily categorised as simply beneficial or adverse, it is difficult to produce a defensible overall prioritisation of catchments. However, the analyses we have done can be used to inform the relative likelihood of different environmental effects arising in particular catchments and hence the extent to which mitigation may be required to address any adverse impacts.

The presence of beavers and their specific activities may be judged in some contexts to be beneficial, and in others problematic. For example dam building could be viewed as contributing positively to flood amelioration, water retention and water purification, whereas localised flooding may lead to land use or infrastructure conflicts. Hence simply categorising impacts as positive or negative, or an opportunity or constraint, tends to oversimplify the complexity of effects. Therefore we have simply tried to quantify the potential for overlap of beaver presence and various interests and to provide some possible interpretation with regard to likely effects.

As in the 2017 ER we have focused on the spatial prediction of where beavers are likely to colonise based our data layer for ‘Potential Core Beaver Woodland’. This GIS layer has been developed based on the following characteristics: areas of suitable broadleaved woodland and shrubs (to provide a food and building source); located within 50m of freshwater; comprised of streams with less than a 15% gradient; and not within tidal areas. At least 1.9km³ of woodland has to occur within 4km river bank sections. Analyses have examined overlap and adjacency of receptors with Potential Core Beaver Woodland as a predictor of the scope for beaver effects.

Some of the analyses examine the overlap of predicted damming activity with specific interests. NatureScot commissioned the University of Exeter to produce a ‘Beaver Dam Capacity’ (BDC) layer for the whole of Scotland in 2020 based on the methods of Graham et al. 2020. The model infers the density of dams that can be supported by stream reaches (111.1m ± 52.5) across a catchment.⁴  Each reach is classified for dam capacity using five categories (Table 7) ranging from ‘none’ (defined as no capacity for damming) to ‘pervasive’ (defined as having a  maximum capacity of 16-40 dams in  1 km of channel) assuming the beaver population is at carrying capacity, i.e. a maximum value.

³ Informed by the scientific literature - Elmeros M, Madsen AB & Berthelsen JP (2003) Monitoring of reintroduced beavers (Castor fiber) in Denmark. Lutra 46(2 ):153–162.

8c. Details of data layers included in national spatial analysis of potential beaver interactions - Population and human health

8d. Details of data layers included in national spatial analysis of potential beaver interactions - Cultural heritage

8e. Details of data layers included in national spatial analysis of potential beaver interactions - Material assets

8f. Details of data layers included in national spatial analysis of potential beaver interactions - Additional layers included in analysis

Prioritisation of catchments based on risks and benefits

Using the data derived from the spatial analyses it should be possible to interrogate what are likely to be the key considerations in terms of beaver risks and opportunities for each catchment. As outlined above, it would not be meaningful to try and combine these rankings, but there are some observations highlighted by the analyses:

• Some of the catchments where there is less overlap with receptors (or interests on which beavers may have an impact) where beaver activity could present a conflict are currently less suitable for beavers in terms of being smaller catchments with less Potential Core Beaver Woodland. We could consider there are catchments where the area of Potential Core Beaver Woodland is currently below a critical level for beaver translocation, although there may be the potential for riparian habitat restoration as part of a catchment management/land use plan.

• Some of the largest catchments feature highly in terms of having larger areas of Potential Core Beaver Woodland and a greater length of watercourse. Thereby these catchments also tend to be those with the largest beaver dam capacity which could present benefits in terms of ecosystem services, but equally these catchments may need extra consideration with regard to monitoring the effects of beaver dams on migratory fish and associated interests (fresh water pearl mussels and otters). More detailed interpretation of beaver dam capacity within catchments may highlight where particular concerns are likely to arise if beaver dams did present a barrier to movement or alter the river morphology to the detriment of such interests.

• Some receptors have a marked geographical distribution such as the classification of woodlands as ‘rainforest’ in the west and aspen woodland (with by far the largest area of aspen woodland occurs in the rivers Spey and Dee catchments). This distribution of rainforest reflects the oceanic influence and the diversity of typical species particularly bryophytes and lichens. To exclude all catchments with rainforest areas from consideration for translocation (‘assumed’ and ‘potential’ categories) would exclude 39 of Scotland’s 138 catchments including some catchments with considerable potential in terms of beaver habitat availability and hydrological benefits. However, there may be particularly sensitive areas where the woodland resource is already fragmented and vulnerable, where beavers could present an additional pressure or require more mitigation. We have highlighted in Annex 3 Table 2 where there is assumed rainforest and the proportion of the rainforest area in the catchment that overlaps with Potential Core Beaver Woodland.

• Additional datasets highlight some of the potential benefits: resilience to drought, amelioration of flood risk, habitat restoration areas.

• Tayside has the largest area of high value agricultural land (LCA 1-3.2) that is predicted to overlap with PCBW in Scotland. From our experience in Tayside, beaver impacts on agriculture have been some of the most challenging impacts to mitigate. Hence in considering the relative risks and benefits of translocations to new catchments, the likelihood of beaver activity leading to agricultural conflicts is suggested to be a key consideration. We have included LCA classes 1-3.2 in the analysis as those most likely to be affected by beaver impacts due to the topography and also the types of crops/value of grazing commonly found on these classes. There is potential for beaver activity to have an economic impact on all classes of agriculture or crofting depending on the local topography and the use/value of the land impacted to the individual business. However at a catchment scale the LCA 1-3.2 analysis is helpful in indicating the likelihood of agricultural land use conflicts. There are 43 catchments where there is no overlap predicted with Potential Core Beaver Woodland as in most cases there is no land with  a LCA class 1-3.2 in the catchment. However, many of these catchments also have a smaller extent of Potential Core Beaver Woodland. Hence considering the 20 catchments with the most potential beaver habitat and then considering the relative extent of Prime Agricultural Land (LCA 1-3.) may be a useful starting point for considering priorities for beaver translocation. In table 12 we highlight the 20 catchments with the largest area of Potential Core Beaver Woodland and order them by the (smallest) area of PAL land. There are 14 catchments with less than 60ha of PAL.

• River Lochy
• River Dee (Solway)
• Loch Fyne Coastal
• River Awe
• River Ness
• River Dee (Grampian)
• River Forth
• Dornoch Coastal
• River Beauly
• River Leven (Loch Lomond)
• Galloway Coastal
• River Nith
• River Spey
• River Deveron

We suggest this list presents a useful starting point for further consideration. It does not take account of all the factors included in the spatial analysis, but may allow some focus for further consideration of potential risks and benefits in each catchment.

Assessing the distribution of Potential Core Beaver Woodland in these catchments it is apparent that a number are made up of more fragmented networks or comprised of different river systems running into the sea. This applies to 79- River Dee (Galloway), 10- Loch Fyne Coastal, 80 Galloway coastal, 30 River Deveron, 35 River Don, 14 Cromarty coastal.  It is also apparent that some catchments would more sensibly be considered together. Including: 9/10/11/12/13 – Dornoch Coastal, Rivers Shin, Cassley, Oykel and Carron; 18/19 – Beauly and Beauly Coastal.

This leaves ten catchments where there is an extensive network of suitable beaver habitat and potentially fewer agricultural land use conflicts.

• River Lochy
• River Awe
• River Ness
• River Dee (Grampian)
• River Forth
• Dornoch Coastal + Oykle, Shin, Cassley, Carron (10+11+12+13)
• River Beauly + coastal (18+19)
• River Leven (Loch Lomond)
• River Nith
• River Spey

We can assess these catchments in terms of the potential opportunities/ conflicts identified in the spatial analysis, but propose that for this year, we prioritise the assessment of environmental effects at the catchment scale taking account of other factors. We have given consideration of linkage to existing beaver populations and thereby reinforcement of these populations. In addition we recognise there is known interest in translocations in certain catchments. Hence this year we propose to carry out an assessment of environmental effects on i) the River Leven (Loch Lomond) and parts of the adjacent River Forth catchment (where beavers are not already present),ii) the River Beauly and Beauly coastal catchments, and iii) the River Spey. Other catchments listed here may be high priorities for subsequent assessments.

National assessment of the environmental effects on key receptors arising from beaver translocations

In 2017 the ER provided a detailed analysis of how the continued presence of beaver could effect a wide range of environmental receptors (interests), the basis of which was set against a number of SEA objectives.

The tables in Section 4 of the 2017 report on interactions between beavers and the various receptors and list the potential positive and negative effects, cumulative impacts and links to appropriate mitigation and monitoring requirements. Our review of changes since 2017 has not highlighted any changes in the types or likelihood of effects, but has highlighted a change in policy context, to the extent we have added an additional objective. Hence we refer to the 2017 ER for the detailed assessment of interactions between beavers and to identify key receptors (interests).

We have not identified any additional risks to the delivery of the SEA objectives that were not discussed in the 2017 report from spatial analysis carried out at a national level, (Table 8). Some of the additional datasets we have included provide an indication of where there are the likely to be the greatest opportunities for beavers to contribute ecosystem services that are likely to bring wider environmental benefits in terms of biodiversity gain, attenuation of flooding, increasing resilience to drought risk, water purification etc.

We will assess the likely importance of particular interactions at the catchment level in the stand-alone reports to be produced for catchments prioritised for assessment.

Table 9: Conclusion regarding the likely effect of a national beaver restoration programme on SEA objectives.

Assessment of alternatives

The alternative scenarios considered in 2017 that were ultimately adopted were a mixture of scenarios 2 and 3, i.e. a preference for natural expansion with restricted further release outwith the existing range. Reflecting on this we could make the following observations:

• The population has expanded more rapidly than anticipated, but in some areas has been limited by man-made barriers and potentially management interventions, thought the status of the population is regarded as improving.
• The approach over the last five years will have limited opportunities for genetic mixing and wider strengthening of the population status.
• That this approach will have geographically limited the ecological benefits of beavers and possibly the potential for beavers to act as a catalyst for habitat restoration.
• The approach may have had a limiting effect on ecotourism and socio-economic opportunities in some areas.
• Equally it will have avoided negative socio-economic impacts or mitigation of impacts on some conservation interests.
• One benefit of the restricted approach was seen to be to allow time to develop research into some of the uncertainties for example; around the potential issues of Atlantic salmon passage or impacts on vulnerable species. To some extent it has not been possible to fully explore these issues because of the limited geographical overlap and types of watercourse found in the beaver policy areas where beavers have been present. Hence some of these uncertainties or questions remain not to be fully answered.
• The restricted range may also have limited the interaction of other herbivore impacts and beavers, which may manifest more in other catchments.
• Another benefit of the restricted approach was seen to be the implementation of legislation and the development of the suite of policies and guidance in the Beaver Management Framework to allow negative impacts to be minimised at the same time as allowing the population to expand naturally.  There has been a lot of progress with establishing and operating the BMF which NatureScot considers to be working effectively, whilst recognising that the impacts and benefits are experienced by different stakeholders. Work is ongoing to trial further mitigation approaches and to secure future rural payment support for adopting practices that will bring a range of environmental benefits including reducing beaver land use conflicts, particularly with agriculture.
• It was considered that as the beaver range expands there would be an increased need for management to reduce human-beaver conflicts. This expectation continues and is reflected in Scotland’s Beaver Strategy.

The Scottish Government announcement in November 2021 effectively signalled a move to scenario 4 previously described ‘Accelerated widespread recolonisation’ and is supported by Scotland’s Beaver Strategy. There is considered to be no reasonable alternative in this case as there has been a Ministerial Direction on the policy, but within this there is scope to consider the appropriateness of releases in particular catchments and how these are prioritised.

The move to scenario 4 has been brought about by the climate and nature crises, the growing evidence of beaver benefits and the accumulated experience of operating the Beaver Management Framework.

It is anticipated that the benefits of beaver restoration will out-weight risks in many new catchments and it remains likely that negative effects can be managed (through species licensing) or mitigated. However there may be catchments or sub-catchments that are viewed as not currently suitable for translocations.

Monitoring Proposals

In 2017 is was outlined that monitoring and research would be driven by an adaptive management approach; with the outcome of monitoring and mitigation allowing changes to be made to the Beaver Management Framework and associated guidance.

The number of designated sites that have been subject to Site Condition Monitoring (SCM) in the last five years has been fewer than expected. Whilst the different levels of SCM now proposed will offer a valuable check on beaver related impacts, this frequency of visits cannot reliably be used as early detection of negative beaver effects and SCM monitoring methods have not been specifically adapted to look for beaver impacts.

We previously stated that species and habitats of conservation importance outwith designated sites would be monitored through other existing surveillance and monitoring activities.

The 2017 ER also alluded that a survey and monitoring programme would be developed through the Scottish Beaver Forum for other interest and a strategy for ‘Monitoring, survey and research (2019-2024) was subsequently developed setting out the seven elements;

The requirements for monitoring of specific interests will be examined in the catchment assessments of the environmental effects of beaver releases and the Habitats Regulations appropriate assessments accompanying these reports again at a catchment level. Whilst some monitoring may be a condition where licences are approved for the release of beavers it is likely that a wider programme of monitoring will continue to be required to continue to learn more about beaver interactions in the Scottish environment and provide assurances where there is the potential for negative effects.

Annexes

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