Caper­cail­lie Rein­force­ment Feas­ib­il­ity Study – Phase 2 Final Report, May 2026

Con­tents

A. Summary………………………………………………………………………………………………………….2 Site selection……………………………………………………………………………………………………2 Pop­u­la­tion viab­il­ity analysis……………………………………………………………………………..3 Logist­ics of pop­u­la­tion reinforcement…………………………………………………………………4 B. Discussion………………………………………………………………………………………………………7 C. Con­clu­sions and caveats…………………………………………………………………………………..7 D. Background……………………………………………………………………………………………………..9 Phase 2 tender brief…………………………………………………………………………………………9 E. Annexes………………………………………………………………………………………………………..11 Annex 1. Phase 2 stake­hold­er ses­sion Fri­day 16 Janu­ary 2026……………………………..11 Annex 2. Site assessment………………………………………………………………………………….19 Annex 3. Tech­nic­al Report: A Pop­u­la­tion Viab­il­ity Ana­lys­is (PVA) to inform rein­force­ment plan­ning and decision-making………………………………………………..26 Annex 4. Logist­ics of pop­u­la­tion reinforcement…………………………………………………..27

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A. Sum­mary

This report is based on three sec­tions look­ing at site selec­tion, pop­u­la­tion viab­il­ity ana­lys­is and the logist­ics of pop­u­la­tion rein­force­ment. A sum­mary for each of the sec­tions is provided here. The full reports are in the Annexes.

Site selec­tion

1. The Caper­cail­lie Emer­gency Plan Pro­gramme Board recom­men­ded focus­ing on Deeside for a poten­tial rein­force­ment pro­gramme at their meet­ing on 16 Decem­ber 2025. Deeside is a former strong­hold for Caper­cail­lie and while num­bers of birds are cur­rently very low, there is still per­ceived to be extens­ive suit­able hab­it­at in the region. In addi­tion, across the area act­ive hab­it­at improve­ment for Caper­cail­lie is under­way. There is lower human dis­turb­ance pres­sure in Deeside, com­pared to Speyside.

2. A hab­it­at assess­ment pro­tocol, focus­sing on brood hab­it­at, was designed based on pre­vi­ous lit­er­at­ure and land man­ager and research­er know­ledge and exper­i­ence. It was developed for use in Deeside with the idea that the feas­ib­il­ity assess­ment and could also be used for oth­er sites in Scot­land as needed. Assess­ment cri­ter­ia were dis­cussed at a stake­hold­er work­shop with land man­agers in Deeside on Janu­ary 16 2026. After dis­cus­sion and sub­sequent feed­back, twelve spe­cif­ic hab­it­at focussed cri­ter­ia were iden­ti­fied along with sev­en wider area criteria.

3. At the work­shop, land man­agers also took part in a map­ping exer­cise to identi­fy sites in Deeside that would be most likely to meet hab­it­at cri­ter­ia and there­fore have the highest poten­tial for rein­force­ment. There was con­sensus that the site with greatest poten­tial took in the Bal­loch­buie SPA with­in Bal­mor­al Estate, Invergeld­er and the FLS Inver forest block, here termed the ​‘Bal­loch­buie / Inver / Gar­mad­die / Invergeld­er’ site.

4. A meet­ing and walkover of part of the site was held with land man­agers from the three land­hold­ings – Bal­mor­al Estate, Inver­cauld Estate and Forest and Land Scot­land — on the 6 Feb­ru­ary 2026 to identi­fy optim­al areas to con­duct the hab­it­at assess­ment. Factors such as ongo­ing and future hab­it­at man­age­ment, access­ib­il­ity for man­age­ment and low human dis­turb­ance were dis­cussed. Three poten­tial loc­a­tions were iden­ti­fied: Bal­loch­buie West; Meall Alvie and the Woods of Garmaddie.

5. In Feb­ru­ary 2026, a total of 514 plots were sur­veyed with­in the site, approx­im­ately 120 plots for each of the three loc­a­tions plus addi­tion­al plots with­in the wider area. Of the three poten­tial loc­a­tions, the Woods of Gar­mad­die had the highest score, mak­ing it the most favour­able of the three sites sur­veyed. Across the wider area most of the cri­ter­ia scored highly, espe­cially for the lack of deer fences / marked deer fences; the pres­ence of open tree can­opy; low deer pres­ence; low human dis­turb­ance and good ground veget­a­tion access for chicks to move around. This sug­gests that the area would be suit­able for most of the cri­ter­ia deemed import­ant for brood sur­viv­al and ulti­mately pop­u­la­tion re-enforcement.

6. The area scored low­est for the cri­ter­ia: pres­ence of ant nests; bog cot­ton; water avail­ab­il­ity; dust baths and the veget­a­tion struc­ture i.e. juni­per like under­story and fallen trees. The lack of water avail­ab­il­ity and bog cot­ton have been noted in pre­vi­ous Caper­cail­lie sur­veys as a fea­ture of the geo­logy and hydro­logy in Deeside. Small scale ditch block­ing has been tak­ing place, e.g. in the Woods of Garmaddie.

Pop­u­la­tion viab­il­ity analysis

1. Work under this sec­tion explored the bene­fit of Caper­cail­lie trans­lo­ca­tions for the population’s long-term viab­il­ity. In par­tic­u­lar, the bene­fits com­pared to the status-quo of a pop­u­la­tion decline were looked at, also under plaus­ible pop­u­la­tion increase scen­ari­os that are pre­dicted under oth­er man­age­ment strategies (com­bin­ing deer fence removals and diver­sion­ary feed­ing of pred­at­ors). Using these two baseline scen­ari­os the import­ance of delayed trans­lo­ca­tions, and clus­ter­ing of trans­lo­ca­tions by lek or year and dens­ity depend­ence were explored.

2. These ques­tions require a reli­able tool for Pop­u­la­tion Viab­il­ity Ana­lys­is (PVA), a rel­ev­ant defin­i­tion of risk and a clear set of envir­on­ment­al and man­age­ment scen­ari­os. The approach taken here for all three of these require­ments is par­tic­u­larly nov­el and meth­od­o­lo­gic­ally effi­cient. Spe­cific­ally, our bespoke defin­i­tion of risk incor­por­ates form­al meas­ures of viab­il­ity and the effects of risk-dis­count­ing for large pop­u­la­tions into the dis­tant future (con­versely, weight­ing risk high­er when pop­u­la­tions are small in the short term). Our imple­ment­a­tion of the Strath­spey PVA is fast, stochast­ic, and fully para­met­er­ized by fit­ting the mod­el to the com­bined pop­u­la­tion and demo­graph­ic data. Finally, using the PVA speed, our scen­ari­os are sys­tem­at­ic­ally explored by auto­mat­ic optim­iz­a­tion of man­age­ment strategies.

3. The mod­el is based on the Strath­spey lek size dis­tri­bu­tion because this is where suf­fi­cient data exis­ted to fit the ori­gin­al mod­el. There is no a‑priori reas­on to believe the para­met­er val­ues are dif­fer­ent, but the smal­ler and more isol­ated leks in Deeside com­pared to Strath­spey, may be sub­ject to qual­it­at­ively dif­fer­ent pres­sures, yet to be pos­tu­lated. Giv­en the over­all estim­ated pop­u­la­tion on Deeside is an order of mag­nitude smal­ler with only a hand­ful of birds remain­ing, it is most sus­cept­ible to chance events (stochasti­city).

4. The mod­el con­tains sev­er­al sim­pli­fy­ing fea­tures and bio­lo­gic­al assump­tions that can read­ily be relaxed in future exten­sions to this work. First, des­pite the abil­ity of the mod­el to incor­por­ate envir­on­ment­al cov­ari­ates (such as the pat­tern of April warm­ing), future pro­jec­tions of such cov­ari­ates are gen­er­ally not avail­able, so even those cov­ari­ates that have pre­vi­ously been found to be influ­en­tial were not incor­por­ated. How­ever, the mod­el accoun­ted for envir­on­ment­al influ­ences (includ­ing those res­ult­ing in cata­stroph­ic events in breed­ing or sur­viv­al) via ran­dom effects whose mag­nitude had been estim­ated dur­ing mod­el fit­ting. Second, no meas­ure of meta­pop­u­la­tion con­nectiv­ity was used between leks in the pop­u­la­tion, merely rep­res­ent­ing exchange of indi­vidu­als by the use of a small res­cue effect in extinct lek. Oth­er val­ues can be rap­idly invest­ig­ated, if required.

5. Man­age­ment under the assump­tion of dens­ity inde­pend­ence showed a near-lin­ear pat­tern of risk reduc­tion with increas­ing num­bers of trans­lo­cated indi­vidu­als (up to 300 over the next 5 years), indic­at­ing mod­est gains via risk reduc­tions (only up to 12% of the bene­fits that could be obtained by deer fence remov­al and diver­sion­ary feed­ing). Intro­du­cing dens­ity depend­ence made little dif­fer­ence either in the over­all risk reduc­tion or the gen­er­al pat­tern of clus­ter­ing across leks and years. So, even though dens­ity depend­ence makes an incre­ment­al dif­fer­ence on indi­vidu­al pro­jec­tion scen­ari­os, it is expec­ted that this will not have a great bear­ing on any decisions about trans­lo­ca­tion strategies. To invest­ig­ate wheth­er delays in imple­ment­ing trans­lo­ca­tion strategies would increase the risk, the ana­lys­is was re-run for five-year trans­lo­ca­tion pro­grams that were ini­ti­ated fur­ther into the future fol­low­ing fur­ther decline. Although this led to a small loss in the effic­acy of risk reduc­tion between the three time win­dows, this is of the order of 2%, an impact that is likely to be undetect­able in a real sys­tem. It is there­fore con­cluded that the small bene­fit likely to be con­ferred by trans­lo­ca­tions is not going to be lost by post­pon­ing them, until more power­ful inter­ven­tions have been examined and attempted

6. Improv­ing base demo­graph­ic rates (via land­scape and diver­sion­ary feed­ing) is, under the most con­ser­vat­ive scen­ari­os, approx­im­ately eight times more effect­ive than dir­ect pop­u­la­tion sub­sidies by trans­lo­ca­tions. Equi­val­ently, based on our mod­el­ling and allow­ing for a 40% sur­viv­al of cap­tive-born indi­vidu­als, it is estim­ated that ~2,500 birds would need to be trans­lo­cated to achieve the same res­ults as oth­er forms of man­age­ment. For com­par­is­on, this would mean pro­du­cing in cap­tiv­ity or import­ing close to four times the estim­ated cur­rent pop­u­la­tion in Strathspey.

7. Over­all, the find­ings clearly indic­ate that for the Spey­side pop­u­la­tion improv­ing hab­it­at con­di­tions and redu­cing causes of mor­tal­ity are more power­ful con­ser­va­tion tools than sup­ple­ment­ing the pop­u­la­tion through releases. In prac­tic­al terms, achiev­ing the same bene­fits as hab­it­at and diver­sion­ary feed­ing would require releas­ing thou­sands of birds, mak­ing trans­lo­ca­tion a rel­at­ively inef­fi­cient strategy on its own.

Logist­ics of pop­u­la­tion reinforcement

1. The aim of this part of the study, was to gath­er inform­a­tion about exist­ing cap­tive breed­ing pro­grammes and exper­i­ence in the UK and Europe to inform decisions around logist­ics asso­ci­ated with sourcing and release of birds. Inform­a­tion was com­piled fol­low­ing ana­lys­is of lit­er­at­ure and cor­res­pond­ence with rel­ev­ant Caper­cail­lie specialists.

2. Egg trans­fer is the delib­er­ate move­ment of wild or cap­tive eggs between loc­a­tions that can sup­port spe­cies recov­ery, such as boost­ing genet­ic diversity, con­ser­va­tion breed­ing, or improv­ing repro­duc­tion. While not com­monly used for Caper­cail­lie, it has been applied in both wild and cap­tive con­texts across the UK and Europe. Dif­fer­ent trans­fer path­ways exist — between wild pop­u­la­tions, cap­tive facil­it­ies, or a mix of both each with spe­cif­ic logist­ic­al and eco­lo­gic­al chal­lenges. Suc­cess­ful trans­fer depends heav­ily on the stage of egg devel­op­ment, as unin­cub­ated eggs are more resi­li­ent, where­as incub­ated eggs require strict tem­per­at­ure con­trol. The pro­cess also demands care­ful hand­ling, detailed know­ledge of nest­ing beha­viour, and effect­ive mon­it­or­ing. How­ever, egg trans­fer car­ries sig­ni­fic­ant risks, includ­ing nest dis­turb­ance, egg dam­age, dis­ease trans­mis­sion, and poten­tial aban­don­ment by females, mean­ing it requires high expert­ise and care­ful plan­ning to bal­ance risks against con­ser­va­tion bene­fits. Egg trans­fers have the poten­tial to play a valu­able role in both Caper­cail­lie recov­ery sup­port how­ever it is recom­men­ded that cap­tive ​“stored” (unin­cub­ated) eggs are the pre­ferred choice giv­en asso­ci­ated risks.

3. Caper­cail­lie have rarely been kept in UK zoos, with only sev­en insti­tu­tions hold­ing them between the 1970s and 2017, and none cur­rently main­tain­ing birds. Today, the UK’s only cap­tive pop­u­la­tion is man­aged by a small group of five private avi­cul­tur­ists, of which four are act­ively breed­ing. This pop­u­la­tion totals around 79 birds, mostly females, and is unevenly dis­trib­uted, with one hold­er man­aging about 60%. All act­ive hold­ers have sig­ni­fic­ant exper­i­ence in breed­ing and man­aging Caper­cail­lie, though none are part of a form­al breed­ing pro­gramme. Their expert­ise is con­sid­er­able, some have been breed­ing caper­cail­lie for over 30 years, and high breed­ing suc­cess has been demon­strated, sug­gest­ing strong poten­tial for future con­ser­va­tion breed­ing efforts if coordin­ated effectively.

4. The European Asso­ci­ation of Zoos and Aquar­ia (EAZA) runs a coordin­ated breed­ing pro­gramme (EEP) for West­ern Caper­cail­lie, led by Sainte Croix Zoo (Moselle France), aimed at sup­port­ing pop­u­la­tion recov­ery, main­tain­ing genet­ic­ally healthy birds for rein­tro­duc­tion, and improv­ing hus­bandry and col­lab­or­a­tion across Europe. The pro­gramme cur­rently includes 15 insti­tu­tions hold­ing 66 birds, with key breed­ing centres such as Bern Zoo and Sainte Croix Zoo pro­du­cing sig­ni­fic­ant num­bers of chicks for release pro­jects. The EEP pro­gramme cur­rently col­lab­or­ates with sev­er­al breed­ing for release pro­jects across Europe provid­ing 20 – 30 birds in 2025. Across Europe, sev­er­al ded­ic­ated breed­ing centres are act­ively releas­ing birds (from both wild and cap­tive source) using mainly soft-release strategies. Dis­cus­sions dur­ing a site vis­it to Scot­land by the EAZA EEP Breed­ing Pro­gramme Coordin­at­or high­lighted the poten­tial for a) breed­ing and trans­fer sup­port for future breed­ing for release of Caper­cail­lie in Scot­land b) poten­tial to explore a com­pli­ment­ary Caper­cail­lie breed­ing pro­gramme for UK man­age­ment under the exist­ing EAZA framework.

5. Anim­al trans­fers for con­ser­va­tion — wheth­er wild or cap­tive — must fol­low strict leg­al and bio­se­c­ur­ity rules, typ­ic­ally includ­ing quar­ant­ine and dis­ease screen­ing to reduce risks to wild­life and people. The level of quar­ant­ine var­ies but often requires a Dis­ease Risk Assess­ment (DRA); how­ever, derog­a­tions (excep­tions) can be gran­ted where strict quar­ant­ine would harm sens­it­ive spe­cies. In the UK, such derog­a­tions have been used for spe­cies like the white-tailed sea eagle and spoon-billed sand­piper to min­im­ise stress while still man­aging dis­ease risk. Across Europe, sim­il­ar approaches have been applied to Caper­cail­lie, includ­ing reduced or no quar­ant­ine for wild-to-wild trans­fers with rap­id dis­ease test­ing, which has proven suc­cess­ful with no recor­ded dis­ease issues. Over­all, while quar­ant­ine is usu­ally required — espe­cially for bird trans­fers — there is grow­ing evid­ence that care­fully man­aged derog­a­tions, sup­por­ted by robust screen­ing pro­to­cols and veter­in­ary over­sight (e.g. through APHA and Scot­tish Gov­ern­ment), can improve sur­viv­al out­comes without increas­ing dis­ease risk.

6. Inform­a­tion from UK private breed­ers and the European zoo breed­ing pro­gramme shows that cap­tive Caper­cail­lie breed­ing fol­lows sim­il­ar social struc­tures (one male with mul­tiple females) but dif­fers sig­ni­fic­antly in rear­ing approaches and enclos­ure qual­ity. Three main rear­ing meth­ods are used — par­ent, hand, and foster rear­ing — each with trade-offs between pro­ductiv­ity and beha­vi­our­al devel­op­ment, with European zoos favour­ing par­ent rear­ing, while UK private breed­ers rely more on hand and foster meth­ods. Tech­niques like double clutch­ing are used to boost pro­ductiv­ity. Suc­cess­ful rear­ing depends on strong para­site con­trol, appro­pri­ate diet, well-designed enclos­ures, skilled staff, and reli­able equip­ment. Over­all, European facil­it­ies tend to provide lar­ger, more nat­ur­al­ist­ic enclos­ures that bet­ter sup­port beha­vi­our­al devel­op­ment, while enclos­ure design (raised vs floored) presents a bal­ance between dis­ease con­trol and nat­ur­al con­di­tions, high­light­ing the need for care­fully planned sys­tems in any future breed­ing-for-release programme.

7. Select­ing source pop­u­la­tions for Caper­cail­lie trans­lo­ca­tions involves bal­an­cing genet­ic, eco­lo­gic­al, wel­fare, dis­ease, and logist­ic­al factors, as well as min­im­ising impacts on donor pop­u­la­tions. Both wild (in-situ) and cap­tive (ex-situ) sources offer advant­ages: cap­tive birds can be bred with lim­ited impact and man­aged more eas­ily, while wild birds already pos­sess nat­ur­al beha­viours and pred­at­or aware­ness. How­ever, risks include inbreed­ing or beha­vi­our­al lim­it­a­tions in cap­tive birds, and stress, pop­u­la­tion impacts, and logist­ic­al chal­lenges for wild sourcing. Genet­ic­ally, Scotland’s pop­u­la­tion is of Northern/​Boreal lin­eage (linked to Scand­inavi­an ori­gins), mak­ing sim­il­ar pop­u­la­tions (e.g. Sweden/​Norway) lower risk, though intro­du­cing dif­fer­ent lin­eages could increase genet­ic diversity if man­aged care­fully. Eco­lo­gic­al and beha­vi­our­al com­pat­ib­il­ity, dis­ease con­sid­er­a­tions, and pop­u­la­tion size/​trends are also crit­ic­al, with lar­ger, stable or increas­ing pop­u­la­tions being prefer­able donors. Over­all, care­ful assess­ment — includ­ing gen­om­ic ana­lys­is and dis­ease screen­ing — is essen­tial to ensure suit­able, low-risk source pop­u­la­tions for suc­cess­ful long-term restoration.

8. Although the gen­om­ic pic­ture is incom­plete and more work is needed, giv­en the cur­rent evid­ence, it is recom­men­ded that if rein­force­ment were to be con­sidered, then indi­vidu­als should be sourced from Nor­way, Sweden (in-situ) and/​or an ex-situ pop­u­la­tion con­sist­ing of genet­ic­ally diverse indi­vidu­als of the European lineage.

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B. Dis­cus­sion

1. Res­ults from the stake­hold­er work­shop sug­ges­ted sup­port for rein­force­ment in Deeside and that the Bal­loch­buie / Inver / Gar­mad­die / Invergeld­er would be the pri­or­ity site for a poten­tial Caper­cail­lie pop­u­la­tion rein­force­ment. Site assess­ment con­firmed that the site scores highly for many of the cri­ter­ia deemed neces­sary for Caper­cail­lie, espe­cially brood hab­it­at. For pos­sible loc­a­tions with­in the site, the Woods of Gar­mad­die scored highest. With­in the wider area there has been a lot of hab­it­at improve­ment work for Caper­cail­lie, which is ongoing.

2. Res­ults from the PVA mod­el­ling tool from Spey­side showed that rel­at­ively large-scale efforts — such as releas­ing up to 300 birds over five years — would achieve only mod­est improve­ments com­pared to remov­ing deer fences and redu­cing pred­a­tion pres­sure through diver­sion­ary feed­ing. It was estim­ated that ~2,500 birds would need to be trans­lo­cated to achieve the same res­ults as oth­er forms of man­age­ment. How­ever, it was noted that smal­ler, more isol­ated pock­ets of Caper­cail­lie, such as those in Deeside, may be char­ac­ter­ized by dif­fer­ent para­met­er val­ues than those estim­ated for Strath­spey which may have a bear­ing on these predictions.

3. Inform­a­tion was gathered about exist­ing cap­tive breed­ing pro­grammes in the UK and Europe. The UK’s cap­tive pop­u­la­tion, 79 birds, is man­aged by a small group of five private avi­cul­tur­ists, of which four are act­ively breed­ing. There is poten­tial for these avi­cul­tur­ists to be part of future con­ser­va­tion breed­ing efforts. The European Asso­ci­ation of Zoos and Aquar­ia (EAZA) runs a coordin­ated breed­ing pro­gramme for Caper­cail­lie, which cur­rently includes 15 insti­tu­tions hold­ing 66 birds, with breed­ing centres pro­du­cing chicks for release pro­jects. This breed­ing pro­gramme could help and form a tem­plate for UK man­age­ment under the EAZA framework.

4. With­in cap­tive breed­ing pop­u­la­tions, three rear­ing meth­ods are used — par­ent, hand, and foster rear­ing — each with trade-offs between pro­ductiv­ity and beha­vi­our­al devel­op­ment. European zoos favour par­ent rear­ing while UK private breed­ers rely more on hand and foster meth­ods. Double clutch­ing is used to boost pro­ductiv­ity. Suc­cess­ful rear­ing requires effect­ive para­site con­trol, diet, well-designed enclos­ures, skilled staff, and reli­able equip­ment. Over­all, European facil­it­ies tend to provide lar­ger, more nat­ur­al­ist­ic enclos­ures that sup­port beha­vi­our­al devel­op­ment, while enclos­ure design (raised vs floored) presents a bal­ance between dis­ease con­trol and nat­ur­al conditions.

C. Con­clu­sions and caveats

1. There was a high level of interest and engage­ment by land man­agers in rein­force­ment in Deeside, and a poten­tial site in Bal­loch­buie / Inver / Gar­mad­die / Invergeld­er was iden­ti­fied, assessed and found to be largely suitable.

2. Res­ults from mod­el­ling the Spey­side pop­u­la­tion, showed that deer fence remov­al and diver­sion­ary feed­ing was more effect­ive than rein­force­ment. On Deeside both these meas­ures are ongo­ing but the pop­u­la­tion is much smal­ler and rap­idly near­ing extinc­tion such that the times­cale for poten­tial recov­ery is extremely chal­len­ging. The Deeside pop­u­la­tion is likely below any ​‘trig­ger point’, although this has not been calculated.

3. The mod­el does not account for the poten­tial effects of ​‘genet­ic res­cue’ which no data are avail­able, nor for what post sur­viv­al rates be for any birds released in Deeside. From a ​‘dis­aster per­spect­ive’ (e.g. fire) the Spey­side pop­u­la­tion is highly vul­ner­able and it may be desir­able to seek to secure caper­cail­lie at mul­tiple sites. If the cur­rent Spey­side pop­u­la­tion recov­ers with in situ meas­ures (as mod­elled) then this pop­u­la­tion could poten­tially provide birds to trans­lo­cate to Deeside.

4. Exist­ing private avi­cul­tur­ists, com­bined with the European Asso­ci­ation of Zoos and Aquar­ia (EAZA) Caper­cail­lie breed­ing pro­gramme could provide a frame­work for a rein­force­ment pro­gramme. Although the gen­om­ic pic­ture is incom­plete and more work is needed, giv­en the cur­rent evid­ence, it is recom­men­ded that indi­vidu­als to be used in a rein­force­ment pro­gram to Scot­land are sourced from Nor­way, Sweden (in-situ) and/​or an ex-situ pop­u­la­tion con­sist­ing of genet­ic­ally diverse indi­vidu­als of the European lin­eage. It is import­ant to note that if trans­lo­ca­tions involving cap­tive birds are to occur then an ini­tial pre­par­at­ory phase (~2 years) to build up the pop­u­la­tion would be required. This would include enhance­ment of man­age­ment facil­it­ies, genet­ic assess­ments of cur­rent cap­tive pop­u­la­tion and stand­ard­ising rear­ing and cap­tive man­age­ment protocols.

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D. Back­ground

The Caper­cail­lie Emer­gency Plan recog­nises that if man­age­ment actions out­lined in the plan are insuf­fi­cient to reverse pop­u­la­tion declines, it may be neces­sary to rein­force the Scot­tish Caper­cail­lie pop­u­la­tion with birds from out­side the UK. The Nation­al Spe­cies Rein­tro­duc­tion For­um has advised that any rein­force­ment be care­fully coordin­ated with ongo­ing con­ser­va­tion efforts. Phase 1 made a num­ber of recom­mend­a­tions on which the Phase 2 tender was based

Phase 2 tender brief

The Phase 2 tender sought the fol­low­ing outputs:

1. A set of poten­tial trans­lo­ca­tion sites iden­ti­fied with the Caper­cail­lie Emer­gency Plan Pro­gramme Board and Sci­entif­ic Advis­ory Group from the fol­low­ing list pri­or­it­ised in Phase 1: Deeside; Spey­side (adja­cent to the exist­ing strong­hold); Caper­cail­lie Spe­cial Pro­tec­ted Areas (SPAs) out­with the Cairngorms Nation­al Park; and oth­er areas of Scotland.

2. A decision-mak­ing frame­work for Caper­cail­lie rein­force­ment site selec­tion which factors in the Scot­tish Con­ser­va­tion Trans­lo­ca­tion Code and is informed by exist­ing data and recog­nised trans­lo­ca­tion plan­ning meth­ods, includ­ing an expert eli­cit­a­tion work­shop, con­vened by the Cairngorms Nation­al Park Authority.

3. Detailed assess­ment and ground-truth­ing of eco­lo­gic­al con­di­tions and risks for the sites selec­ted using the decision-mak­ing framework.

4. Site selec­tion a. A com­pre­hens­ive report for each site selec­ted using the decision-mak­ing frame­work, eval­u­at­ing the eco­lo­gic­al suit­ab­il­ity and asso­ci­ated risks of each site. b. In par­al­lel, the Cairngorms Nation­al Park Author­ity will begin dis­cus­sions with landown­ers and man­agers to explore poten­tial interest in host­ing a rein­force­ment release, and will engage with those respons­ible for poten­tial sites iden­ti­fied with the Caper­cail­lie Emer­gency Plan Pro­gramme Board and Sci­entif­ic Advis­ory Group. c. A pro­gramme of loc­al com­munity con­sulta­tion will also be under­taken by the Cairngorms Nation­al Park Author­ity to gauge sup­port, identi­fy poten­tial con­cerns, and explore oppor­tun­it­ies for co-design­ing the imple­ment­a­tion of any future rein­force­ment. It is expec­ted that the con­tract­or will work closely with the Cairngorms Nation­al Park Author­ity on deliv­er­ing this work, includ­ing present­ing find­ings and help­ing to answer ques­tions that arise from com­munit­ies, and landown­ers and managers.

5. A Pop­u­la­tion Viab­il­ity Ana­lys­is (PVA) to inform rein­force­ment plan­ning and decision-mak­ing. The ana­lys­is will provide: a. A rationale for a ​‘trig­ger point’ for when to move for­ward with rein­force­ment. b. Evid­ence to under­stand the neces­sary car­ry­ing capa­city of a release site, to sup­port final site selec­tion decisions. c. Evid­ence on the num­ber of birds that would be needed to carry out a rein­force­ment, and what a sus­tain­able sur­viv­al level would need to be.

6. A final report with spe­cif­ic rein­force­ment inform­a­tion assessed in more detail, includ­ing: a. Logist­ics of egg trans­fer (how long are they viable etc.) b. The status of the cur­rent UK ex-situ pop­u­la­tion – num­bers and proven­ance c. Status of wider European ex-situ pop­u­la­tion, espe­cially in EAZA accred­ited zoos d. Feas­ib­il­ity of obtain­ing derog­a­tions on quar­ant­ine require­ments for import­ing birds or eggs from Europe e. Expert inter­views to pro­duce a short review of cur­rent know­ledge on ex-situ Caper­cail­lie rear­ing and repro­duc­tion, includ­ing dir­ect engage­ment with exist­ing rein­force­ment and rein­tro­duc­tion pro­jects across Europe, to assess the range of meth­ods and tech­niques being used and the evid­ence avail­able on their suc­cess f. Eval­u­ation of poten­tial in-situ source pop­u­la­tions in Europe, informed by con­sulta­tion with man­agers of cur­rent European rein­force­ment pro­jects and rel­ev­ant experts, to identi­fy suit­able pop­u­la­tions and under­stand asso­ci­ated man­age­ment prac­tices and genet­ic considerations.

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E. Annexes

Annex 1. Phase 2 stake­hold­er ses­sion Fri­day 16 Janu­ary 2026

Caper­cail­lie rein­force­ment feas­ib­il­ity study Phase 2 stake­hold­er session Fri­day 16 Janu­ary | 10.30am – 12.30pm | Bal­mor­al Estate

Attendees Adam Smith (Glen Tanar), Andy Dav­is (FLS), Car­o­lyn Robertson (Park Author­ity), Claire Smith (RSPB Cran­nach), Glyn Jones (Bal­mor­al), Helen Gray (RSPB), Ian Hill (Inver­cauld), Mal­colm Nicol (Bal­lo­gie), Mark Brazend­ale (Abergel­die), Mark Nicolson (Mar Estate), Mike Daniels (UHI), Mike Smed­ley (NatureScot), Paul Chap­man (SAC Con­sult­ing), Ros­alind Bryce (UHI), Ryan Cum­ming (Abergel­die), Shaila Rao (Mar Lodge), Simon Ritch­ie (NatureScot, Muir of Din­net), Xavi­er Lambin (Uni­ver­sity of Aberdeen)

Back­ground The aim of this stake­hold­er ses­sion was to con­tin­ue work out­lined in the Caper­cail­lie Emer­gency Plan to eval­u­ate the feas­ib­il­ity of rein­for­cing the Scot­tish caper­cail­lie population.

Fol­low­ing a stake­hold­er work­shop held in May (2025) to inform Phase 1, the pro­ject has moved into its next stage. A Phase 2 con­tract has been awar­ded to a deliv­ery team from the Uni­ver­sity of the High­lands and Islands (UHI), the Roy­al Zoolo­gic­al Soci­ety of Scot­land (RZSS), the Uni­ver­sity of Glas­gow, and the Uni­ver­sity of Aberdeen.

This ses­sion focused on pro­gress­ing the work in more detail, ini­tially with landown­ers and man­agers in Deeside, mem­bers of the Sci­entif­ic Advis­ory Group for the Caper­cail­lie Emer­gency Plan and the RSPB Caper­cail­lie Advis­ory Officer, to:

• Identi­fy poten­tial rein­force­ment sites in Deeside for assess­ment; and
• Agree the cri­ter­ia that will be used to assess those sites as part of the feas­ib­il­ity study

Dur­ing Phase 1, Deeside was iden­ti­fied as the highest-pri­or­ity area for fur­ther invest­ig­a­tion from a list of poten­tial trans­lo­ca­tion sites and is there­fore the focus for this more detailed assess­ment. The full Phase 1 report is avail­able on the Cairngorms Nation­al Park web­site here.

Draft cri­ter­ia for assess­ing poten­tial rein­force­ment sites in Deeside

Cop­ies of a draft cri­ter­ia table were dis­trib­uted and dis­cussed with­in small groups. There was gen­er­al agree­ment on addi­tion­al factors that should be con­sidered. A sum­mary of the dis­cus­sion points is provided below and the amended table is presen­ted as Table 1 (page 19)

Main dis­cus­sion points

• It was sug­ges­ted that the table of cri­ter­ia could be re-mod­elled as a decision mat­rix to guide the research team, and ulti­mately land man­agers through an eval­u­ation pro­cess. This could begin with the most import­ant cri­ter­ia and con­sist of a series of ques­tions to ascer­tain the suit­ab­il­ity of a site.
• It was noted that some cri­ter­ia are fixed attrib­utes of a site that can’t be influ­enced through man­age­ment while oth­ers are dir­ectly related to man­age­ment decisions e.g. diver­sion­ary feed­ing. It was sug­ges­ted that any weight­ing of cri­ter­ia should reflect this.
• It was noted that suit­able hab­it­at is highly likely to cross mul­tiple land-own­er­ship bound­ar­ies. It is neces­sary that site eval­u­ations are done col­lab­or­at­ively to loc­ate the best con­tinu­ous site conditions.
• Con­nectiv­ity is not cur­rently included in the table. This should be con­sidered as there is the poten­tial for sites along Deeside to be recol­on­ised. The poten­tial for hens to dis­perse over long dis­tances was highlighted.
• Con­nectiv­ity could be assessed in terms of prox­im­ity to oth­er caper­cail­lie areas / sites assessed as suit­able for caper­cail­lie. It was also recom­men­ded to include where a site is in rela­tion to the wider range e.g. cent­rally or on the edge.
• It was sug­ges­ted that it may be help­ful to include inform­a­tion about how recently caper­cail­lie were lost from the site, as this may be an indic­at­or of cur­rent hab­it­at qual­ity. There is poten­tial to also include cause of death for last caper­cail­lie recor­ded at a site (if known) as this may provide insights into pres­sure from dogs, pred­at­ors etc.
• It is recom­men­ded that the sex of exist­ing caper­cail­lie is included, with the pres­ence of hens weighted more favourable.
• It was sug­ges­ted that con­nectiv­ity and patch size need to be looked at togeth­er to identi­fy the most suit­able sites. A ques­tion was raised about the extent to which caper­cail­lie can / will cross open ground so the sig­ni­fic­ance of this can be eval­u­ated in poten­tial sites. Edge effect should also be con­sidered as a factor. There