Assessment of the potential for Eurasian beavers to naturally colonise in CNP

An assess­ment of the poten­tial for Euras­i­an beavers to nat­ur­ally col­on­ise the Cairngorms Nation­al Park

Risks and oppor­tun­it­ies asso­ci­ated with their presence

Pre­pared for Cairngorms Nation­al Park Feb­ru­ary 2022

Dr Róisín Camp­bell-Palmer¹, Prof Richard Bra­zi­er and Dr Alan Put­tock Cov­er photo: River Luineag in Cairngorms Nation­al park © Alan Put­tock ¹Lead Con­tact: Dr Róisín Camp­bell-Palmer Email: rcampbellpalmer@​gmail.​com

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Con­tents Over­view and Scope…………………………………………………………………………………………………………………….. 4 Status of Beavers in Scot­land………………………………………………………………………………………………………. 4 The Beaver and its Recov­ery…………………………………………………………………………………………………………. 5 Review of Beaver Envir­on­ment­al and Socio-Eco­nom­ic Impacts………………………………………………………. 6 Desktop Ana­lys­is of Beaver Hab­it­at and Dam Capa­city in Cairngorms Nation­al Park………………………… 8 Sum­mary……………………………………………………………………………………………………………………………………. 8 Mod­el­ling of beaver hab­it­at suit­ab­il­ity………………………………………………………………………………………….. 9 Beaver Hab­it­at Suit­ab­il­ity Mod­el­ling………………………………………………………………………………………….. 9 Beaver Veget­a­tion Index (BVI –pre­requis­ite for BHI mod­el­ling)……………………………………………………. 9 2.3. Beaver Hab­it­at Index mod­el (BHI)……………………………………………………………………………………… 10 Beaver Hab­it­at Index maps and sum­mary stat­ist­ics for study area……………………………………………….. 11 Beaver Dam Capa­city mod­el­ling…………………………………………………………………………………………………. 14 Beaver Dam Capa­city (BDC) mod­el sum­mary……………………………………………………………………………. 14 Beaver Dam Capa­city Mod­el maps for the study area………………………………………………………………….. 16 Beaver hab­it­at and dam capa­city mod­el con­clu­sions and next steps……………………………………………… 19 Sum­mary of Field Based Assess­ment…………………………………………………………………………………………… 20 Desk and Field Based Assess­ment of the Abil­ity of Beavers to Nat­ur­ally Spread from Exist­ing Areas 20 Sum­mary of 2021 beaver activ­ity in Tay­side and Forth catch­ments………………………………………………. 20 Main poten­tial access routes into Cairngorms con­sidered……………………………………………………………. 22

1. Via head­wa­ters of River Spey……………………………………………………………………………………………….. 22
2. Via Loch Lag­gan………………………………………………………………………………………………………………….. 24
3. Via Loch Ericht, Loch Ran­noch and Loch Tum­mel…………………………………………………………………….. 25
4. River Tilt……………………………………………………………………………………………………………………………… 28
5. River Isla and Neigh­bour­ing Channels/​Burns………………………………………………………………………….. 29 Desk and Field Assess­ment of Beaver Suit­ab­il­ity of Sites with­in Cairngorms Nation­al Park………………. 30 River Spey………………………………………………………………………………………………………………………………… 30 Main River Spey……………………………………………………………………………………………………………………… 30 RSPB Insh Marshes…………………………………………………………………………………………………………………. 31 River Luineag to Above Loch Mor­lich……………………………………………………………………………………….. 32 Loch Garten……………………………………………………………………………………………………………………………. 34 River Avon……………………………………………………………………………………………………………………………….. 34 River Don………………………………………………………………………………………………………………………………… 35 River Dee………………………………………………………………………………………………………………………………… 37 Loch Kinord…………………………………………………………………………………………………………………………….. 40 Man­age­ment and Mit­ig­a­tion Oppor­tun­it­ies…………………………………………………………………………………. 42

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Sum­mary of Risks and Oppor­tun­it­ies with­in Cairngorms Nation­al Park………………………………………… 45 Desk and Field Assess­ment of poten­tial con­flict with agri­cul­tur­al land and fish­ing beats with­in Cairngorms Nation­al Park………………………………………………………………………………………………………….. 46 Recom­mend­a­tions for ​‘pre­par­a­tion for arrival’…………………………………………………………………………….. 51 Con­clu­sion………………………………………………………………………………………………………………………………… 51 Ref­er­ences……………………………………………………………………………………………………………………………….. 52 Appen­dices………………………………………………………………………………………………………………………………. 57 Appendix 1: Review of Impacts of beaver return (Adap­ted from Bra­zi­er et al., 2021)……………………. 57

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