Nest boxes represent a popular tool to support secondary cavity-nesting species. Surprisingly, the benefits and limitations of nest boxes for target species in different environments are poorly understood. We performed a 3-years experimental study in two different Central European forests to evaluate nest box use and breeding performance of boreal owl (Aegolius funereus) - a species well known for its readiness to occupy nest boxes. Based on territorial vocalisation, two boreal owl populations 200 km apart were similarly abundant in their environments. However, only the boreal owl population in young restored Norway (Picea abies) and blue (Picea pungens) spruce-dominated forests on mountain plateaus readily occupied nest boxes with the occupancy reaching 8-15%. Nest boxes lost their supporting function for the boreal owl in mature Scots pine (Pinus sylvestris)-dominated forests in the lowland, where the nest box occupancy reached 0-1%. As a result, the population of boreal owls that used nest boxes in the young restored forests produced 10 times more fledglings than the population inhabiting mature Scots pine forests. We explain the differences by the contrasting availability of natural tree cavities between the two study areas being much higher in mature Scots pine forests. For the first time, this study documents differences in nest box use despite similar food availability and population size of the target species. The study provides the findings-related recommendations for deploying nest boxes for boreal owls and points out a general lack of practical guides.

Faculty of Agrobiology Food and Natural Resources Czech University of Life Sciences Prague Kamýcká 129 165 00 Praha Suchdol Czech Republic

Faculty of Environmental Sciences Czech University of Life Sciences Prague Kamýcká 129 165 00 Praha Suchdol Czech Republic

Faculty of Science University of South Bohemia Branišovská 1760 370 05 České Budějovice Czech Republic

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Mikusiński G, Roberge JM, Fuller RJ. Ecology and Conservation of Forest Birds. Cambridge University Press; 2018.

Newton I. The role of nest sites in limiting the numbers of hole-nesting birds: a review. Biol. Conserv. 1994;70:265–276. doi: 10.1016/0006-3207(94)90172-4. DOI

Korpimäki E, Hakkarainen H. The Boreal Owl: Ecology, Behaviour and Conservation of a Forest-Dwelling Predator. Cambridge University Press; 2012.

Glutz von Blotzheim, U. N. & Bauer, K. M. Handbuch der Vögel Mitteleuropas. Band 9. (Akademische Verlagsgesellschaft, 1980).

Newton I. Population Limitation in Birds. Academic press; 1998.

Moning C, Müller J. Environmental key factors and their thresholds for the avifauna of temperate montane forests. For. Ecol. Manag. 2008;256:1198–1208. doi: 10.1016/j.foreco.2008.06.018. DOI

Walankiewicz W, Czeszczewik D, Stański T, Sahel M, Ruczyński I. Tree cavity resources in spruce-pine managed and protected stands of the Białowieża Forest, Poland. Nat. Areas J. 2014;34:423–428. doi: 10.3375/043.034.0404. DOI

Lambrechts MM, et al. The design of artificial nestboxes for the study of secondary hole-nesting birds: a review of methodological inconsistencies and potential biases. Acta Ornithol. 2010;45:1–26. doi: 10.3161/000164510X516047. DOI

Lambrechts MM, et al. Nest box design for the study of diurnal raptors and owls is still an overlooked point in ecological, evolutionary and conservation studies: a review. J. Ornithol. 2012;153:23–34. doi: 10.1007/s10336-011-0720-3. DOI

Zárybnická M, Kubizňák P, Šindelář J, Hlaváč V. Smart nest box: a tool and methodology for monitoring of cavity-dwelling animals. Methods Ecol. Evol. 2016;7:483–492. doi: 10.1111/2041-210X.12509. DOI

Kubizňák P, et al. Designing network-connected systems for ecological research and education. Ecosphere. 2019;10(6):e02761. doi: 10.1002/ecs2.2761. DOI

Mänd R, Tilgar V, Lõhmus A, Leivits A. Providing nest boxes for hole-nesting birds—Does habitat matter? Biodivers. Conserv. 2005;14:1823–1840. doi: 10.1007/s10531-004-1039-7. DOI

König C, Weick F. Owls of the World. 2. Christopher Helm; 2008.

Morelli F, Benedetti Y, Møller AP, Fuller RA. Measuring avian specialization. Ecol. Evol. 2019;9:8378–8386. doi: 10.1002/ece3.5419. PubMed DOI PMC

Ševčík R, Riegert J, Šťastný K, Zárybnický J, Zárybnická M. The effect of environmental variables on owl distribution in Central Europe: A case study from the Czech Republic. Ecol. Inform. 2021;64:101375. doi: 10.1016/j.ecoinf.2021.101375. DOI

Brambilla M, et al. Species interactions and climate change: How the disruption of species co-occurrence will impact on an avian forest guild. Glob. Change Biol. 2020;26:1212–1224. doi: 10.1111/gcb.14953. PubMed DOI

Hayward GD, Hayward PH, Garton EO. Ecology of boreal owl in the northern Rocky-Mountains, USA. Wildl. Monogr. 1993;124:3–59.

Zárybnická M, Riegert J, Šťastný K. The role of Apodemus mice and Microtus voles in the diet of the Tengmalm’s owl in Central Europe. Popul. Ecol. 2013;55:353–361. doi: 10.1007/s10144-013-0367-4. DOI

Zárybnická M, Sedláček O, Salo P, Šťastný K, Korpimäki E. Reproductive responses of temperate and boreal Tengmalm's owl Aegolius funereus populations to spatial and temporal variation in prey availability. Ibis. 2015;157:369–383. doi: 10.1111/ibi.12244. DOI

Mossop, D. H. The importance of old growth refugia in the Yukon boreal forest to cavity-nesting owls in Biology and Conservation of Owls of the Northern Hemisphere (eds. Duncan, J. R., Johnson, D. H. & Nicholls, T. H.) 584–586 (Forest Service General Technical Report GTR-NC-190, 1997).

Domahidi, Z., Nielsen, S., Bayne, E. & Spence, J. Boreal owl (Aegolius funereus) and northern saw-whet owl (Aegolius acadicus) breeding records in managed boreal forests. Can. Field-Nat.134, 125–131. 10.22621/cfn.v134i2.2146 (2020).

Whitman JS. Diets of nesting boreal owls, Aegolius funereus, in western interior Alaska. Can. Field-Nat. 2001;115:476–479.

Whitman JS. Post-fledging estimation of annual productivity in boreal owls based on prey detritus mass. J. Raptor Res. 2008;42:58–60. doi: 10.3356/JRR-06-88.1. DOI

Anderson, A. G. Wildfire impacts on nest provisioning and survival of Alaskan boreal owls. Master thesis, Miami University, Ohio (2017).

Hayward GD, Steinhorst RK, Hayward PH. Monitoring boreal owl populations with nest boxes: sample size and cost. J. Wildl. Manage. 1992;56:777–785. doi: 10.2307/3809473. DOI

Koopman ME, McDonald DB, Hayward GD. Microsatellite analysis reveals genetic monogamy among female boreal owls. J. Raptor Res. 2007;41:314–318. doi: 10.3356/0892-1016(2007)41[314:MARGMA]2.0.CO;2. DOI

Fang Y, Tang S-H, Gu Y, Sun Y-H. Conservation of Tengmalm's owl and Sichuan wood owl in Lianhuashan Mountain, Gansu, China. Ardea. 2009;97:649–649. doi: 10.5253/078.097.0437. DOI

Löfgren O, Hörnfeldt B, Carlsson B. Site tenacity and nomadism in Tengmalm's owl (Aegolius funereus (L.)) in relation to cyclic food production. Oecologia. 1986;69:321–326. doi: 10.1007/BF00377051. PubMed DOI

Hörnfeldt B, Nyholm NEI. Breeding performance of Tengmalm's owl in a heavy metal pollution gradient. J. Appl. Ecol. 1996;33:377–386. doi: 10.2307/2404759. DOI

Hipkiss T, Hörnfeldt B, Eklund U, Berlin S. Year-dependent sex-biased mortality in supplementary-fed Tengmalm's owl nestlings. J. Anim. Ecol. 2002;71:693–699. doi: 10.1046/j.1365-2656.2002.t01-1-00635.x. DOI

Hipkiss T, Gustafsson J, Eklund U, Hörnfeldt B. Is the long-term decline of boreal owls in Sweden caused by avoidance of old boxes? J. Raptor Res. 2013;47:15–20. doi: 10.3356/JRR-11-91.1. DOI

Korpimäki E. Selection for nest-hole shift and tactics of breeding dispersal in Tengmalm's owl Aegolius funereus. J. Anim. Ecol. 1987;56:185–196. doi: 10.2307/4808. DOI

Drdáková-Zárybnická M. Breeding biology of the Tengmalm's owl (Aegolius funereus) in air-pollution damaged areas of the Krušné hory Mts. Sylvia. 2003;39:35–51.

Zárybnická M, Riegert J, Kloubec B, Obuch J. The effect of elevation and habitat cover on nest box occupancy and diet composition of boreal owls Aegolius funereus. Bird Study. 2017;64:222–231. doi: 10.1080/00063657.2017.1316236. DOI

Zárybnická M, Kloubec B, Obuch J, Riegert J. Fledgling productivity in relation to diet composition of Tengmalm's owl Aegolius funereus in Central Europe. Ardeola. 2015;62:163–171. doi: 10.13157/arla.62.1.2015.163. DOI

Kloubec B. Breeding of Tengmalm's owls (Aegolius funereus) in nest-boxes in Šumava Mts.: a summary from the years 1978–2002. Buteo. 2003;13:75–86.

Flousek, J. Ochrana sov v Krkonošském národním parku in Sovy 1986 (eds. Sitko, J. & Trpák, P.) 33–34 (Státní ústav památkové péče a ochrany přírody, Přerov, 1988).

Ravussin P-A, et al. Quel avenir pour la Chouette de Tengmalm Aegolius funereus dans le massif du Jura? Bilan de trente années de suivi. Nos Oiseaux. 2015;62:5–28.

Schelper W. Zur Brutbiologie, Ernährung und Populationsdynamik des Rauhfusskauzes Aegolius funereus im Kaufunger Wald (Südniedersachsen) Vogelkundliche Berichte aus Niedersachsen. 1989;21:33–53.

Schwerdtfeger, O. The dispersion dynamics of Tengmalm's owl Aegolius funereus in Central Europe in Raptor Conservation Today (eds. Meyburg, B. U. & Chancellor, R. C.) 543–550 (World Working Group on Birds of Prey and Pica Press, 1994).

Hunke W. Versuch eine Population des Raufußkauzes Aegolius funereus durch Anbringen von Nistkästen in den Jahren 1980 bis 2010 zu fördern. Charadrius. 2011;47:93–101.

Mezzavilla, F. & Lombardo, S. Indagini sulla biologia riproduttiva della civetta capogrosso Aegolius funereus: anni 1987–2012 in Atti Secondo Convegno Italiano Rapaci Diurni e Notturni Vol. 3 (eds. Mezzavilla, F. & Scarton, F.) 261–270 (Associazione Faunisti Veneti, Quaderni Faunistici, 2013).

Rajković D. Diet composition and prey diversity of Tengmalm’s owl Aegolius funereus (Linnaeus, 1758; Aves: Strigidae) in central Serbia during breeding. Turk. J. Zool. 2018;42:346–351. doi: 10.3906/zoo-1709-28. DOI

Zárybnická M, Riegert J, Šťastný K. Non-native spruce plantations represent a suitable habitat for Tengmalm's owl (Aegolius funereus) in the Czech Republic, Central Europe. J. Ornithol. 2015;156:457–468. doi: 10.1007/s10336-014-1145-6. DOI

Kopáček J, Veselý J. Sulfur and nitrogen emissions in the Czech Republic and Slovakia from 1850 till 2000. Atmos. Environ. 2005;39:2179–2188. doi: 10.1016/j.atmosenv.2005.01.002. DOI

Kloubec, B., Hora, J. & Šťastný, K. (eds.). Ptáci jižních Čech (Jihočeský kraj, 2015).

Ševčík R, Riegert J, Šindelář J, Zárybnická M. Vocal activity of the Central European boreal owl population in relation to varying environmental conditions. Ornis Fenn. 2019;96:1–12.

Savický, J. AM Services - Play Spectrogram Screens v. 4v7 (Czech Republic, 2009).

Korpimäki E. Diet of breeding Tengmalm’s owls Aegolius funereus: long-term changes and year-to-year variation under cyclic food conditions. Ornis Fenn. 1988;65:21–30.

Kouba M, et al. Home range size of Tengmalm's owl during breeding in Central Europe is determined by prey abundance. PLoS ONE. 2017;12:e0177314. doi: 10.1371/journal.pone.0177314. PubMed DOI PMC

Zárybnická M, Sedláček O, Korpimäki E. Do Tengmalm’s owls alter parental feeding effort under varying conditions of main prey availability? J. Ornithol. 2009;150:231–237. doi: 10.1007/s10336-008-0342-6. DOI

R Core Team. R: A Language and Environment for Statistical Computing (R Foundation for Statistical Computing, Vienna, Austria, 2020).

ter Braak, C. & Šmilauer, P. Canoco Reference Manual and User's Guide: Software for Ordination, version 5.10. (Microcomputer Power, 2018).

Kosiński Z, Kempa M. Density, distribution and nest-sites of woodpeckers Picidae, in a managed forest of Western Poland. Pol. J. Ecol. 2007;55:519–533.

Miller KE. Nest-site limitation of secondary cavity-nesting birds in even-age southern pine forests. Wilson J. Ornithol. 2010;122:126–134. doi: 10.1676/07-130.1. DOI

Sonerud GA. Nest hole shift in Tengmalm's owl Aegolius funereus as defence against nest predation involving long-term memory in the predator. J. Anim. Ecol. 1985;54:179–192. doi: 10.2307/4629. DOI

Sonerud GA. Reduced predation by pine martens on nests of Tengmalm's owl in relocated boxes. Anim. Behav. 1989;37:332–334. doi: 10.1016/0003-3472(89)90122-X. DOI

Sonerud GA. Win - and stay, but not too long: cavity selection by boreal owls to minimize nest predation by pine marten. J. Ornithol. 2021;162:839–855. doi: 10.1007/s10336-021-01876-y. DOI

Korpimäki E. Does nest-hole quality, poor breeding success or food depletion drive the breeding dispersal of Tengmalm's owls? J. Anim. Ecol. 1993;62:606–613. doi: 10.2307/5382. DOI

Hruška F. The boreal owl (Aegolius funereus) - breeding distribution, numbers, ringing results and notes on the breeding biology and feeding ecology of this species in the central part of the Jihlavské vrchy Hills. Crex. 2020;38:112–150.

Broughton R, et al. Nest-site competition between bumblebees (Bombidae), social wasps (Vespidae) and cavity-nesting birds in Britain and the Western Palearctic. Bird Study. 2015;62:427–437. doi: 10.1080/00063657.2015.1046811. DOI

Pawlikowski, T. & Pawlikowski, K. Nesting interactions of the social wasp Dolichovespula saxonica [F.] (Hymenoptera: Vespinae) in wooden nest boxes for birds in the forest reserve „Las Piwnicki” in the Chełmno Land (Northern Poland). Ecol. Quest.13, 67–72. 10.2478/v10090-010-0017-9 (2010).

Langowska A, Ekner-Grzyb A, Skórka P, Tobółka M, Tryjanowski P. Nest-site tenacity and dispersal patterns of Vespa crabro colonies located in bird nest-boxes. Sociobiology. 2010;56:375–382.

Meyer W. Mit welchem Erfolg nutzt der Rauhfusskauz Aegolius funereus (L.) Natruhölen und Nistkästen zur Brut. Vogelwelt. 2003;124:325–331.

López BC, et al. Nest-box use by boreal owls (Aegolius funereus) in the Pyrenees Mountains in Spain. J. Raptor Res. 2010;44:40–49. doi: 10.3356/JRR-09-32.1. DOI

Zárybnická M, Riegert J, Kouba M. Indirect food web interactions affect predation of Tengmalm's owls Aegolius funereus nests by pine martens Martes martes according to the alternative prey hypothesis. Ibis. 2015;157:459–467. doi: 10.1111/ibi.12265. DOI

Zárybnická M, Vojar J. Effect of male provisioning on the parental behavior of female boreal owls Aegolius funereus. Zool. Stud. 2013;52:36. doi: 10.1186/1810-522X-52-36. DOI

Llambías P, Fernandez G. Effects of nestboxes on the breeding biology of southern house wrens Troglodytes aedon bonariae in the southern temperate zone. Ibis. 2009;151:113–121. doi: 10.1111/j.1474-919X.2008.00868.x. DOI

Vrezec A. Breeding density and altitudinal distribution of the Ural, tawny, and boreal owls in North Dinaric Alps (Central Slovenia) J. Raptor Res. 2003;37:55–62.