Increasing numbers of wintering forest birds in Swedish Lapland 1986–2017 show stronger correlations with forest development than with local weather


  • Björn Ferry
  • Håkan Rune
  • Ulf Andersson
  • Martin Green



climate change, Community Temperature Index, forest variables, point counts, survey


After a long period of decline, the number of forest birds has increased in Sweden in recent decades. Whether this trend is due to an increase in forested area, forest quality, climate change, or a combination of these factors, remains unclear. Here, we compared forest bird data from a local winter point count route around Storuman in Swedish Lapland between 1986 and 2017, with the development of regional forest composition and local weather conditions. We suggest that rather than changes in average annual, winter, or summer local temperatures or precipitation, the main drivers behind increasing numbers of wintering forest birds in this part of Sweden are an increase in the area of denser forest and dead wood volume, and a decrease in open ground area without forest vegetation. While there may be supplementary explanations behind the increasing numbers of forest birds, such as reduced agriculture, decreasing local human population, or stronger photosynthesis, our results indicate that local land use has been favourable for forest birds in recent decades in this area.


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Author Biography

Martin Green

Researcher, Lund University


Andersson J, Hjältén J & Dynesius M. 2015. Wood-inhabiting beetles in low stumps, high stumps and logs on boreal clear-cuts: implications for dead wood management. PLoS One 10: e0118896.

Angelstam P, Dönz-Breuss M & Roberge J-M. 2004. Targets and tools for the maintenance of forest biodiversity – an introduction. Ecological Bulletins 51: 11–24.

Basile M, Mikusiński G & Storch I. 2019. Bird guilds show different responses to tree retention levels: a meta-analysis. Global Ecology and Conservation 18: e00615.

Barbet-Massin M, Thuiller W & Jiguet F. 2012. The fate of European breeding birds under climate, land-use and dispersal scenarios. Global Change Biology 18: 881–890.

Bush T. 2010. Biodiversity and sectoral responsibility in the develop­ment of Swedish Forestry Policy, 1988–1993. Scandinavian Journal of History 35: 471–498.

Cardinale BJ, Duffy JE, Gonzalez A, Hooper DU, Perrings C, Venail P, Narwani A, Mace GM, Tilman D, Wardle DA, Kinzig AP, Daily GC, Loreau M, Grace JB, Larigauderie A, Srivastava DS & Naeem S. 2012. Biodiversity loss and its impact on humanity. Nature 486: 59–67.

Daniel WW. 1990. Spearman rank correlation coefficient. Pp. 358–365 in: Applied Nonparametric Statistics (2nd edition). PWS-Kent, Boston.

Devictor V, Julliard R, Couvet D & Jiguetet F. 2008. Birds are tracking climate warming, but not fast enough. Proceedings of the Royal Society B 275: 2743–2748.

Fernández-Martínez M, Sardans J, Chevallier F, Ciais P, Obersteiner M, Vicca S, Canadell JG, Bastos A, Friedlingstein P, Sitch S, Piao SL, Janssen IA & Peñuelas J. 2019. Global trends in carbon sinks and their relationships with CO2 and temperature. Nature Climate Change 9: 73–79.

Forkel M, Carvalhais N, Rödenbeck C, Keeling R, Heinmann M, Thonicke K, Zaehle S & Reichstein M. 2016. Enhanced seasonal CO2 exchange caused by amplified plant productivity in northern ecosystems. Science 351: 696–699.

Forslund M. 2003. Fågelfaunan i olika skogsmiljöer – en studie på beståndsnivå. Skogsstyrelsens rapport 2003:2. Skogsstyrelsens förlag, Jönköping. Available at

FSC. 2019. Svensk statistik – Statistik och Fakta. Retrieved 2 April 2019 from

Godet L, Jaffré M & Devictor V. 2011. Waders in winter: long-term changes of migratory bird assemblages facing climate change. Biology Letters 7: 714–717.

Green M, Haas F & Lindström Å. 2019. Monitoring population changes of birds in Sweden. Annual report for 2018. Department of Biology, Lund University, Lund. 92 pp. Available at

Haas F, Barbet-Massin M, Green M, Jiguet F & Lindström Å. 2014. Species turnover in the Swedish bird fauna 1850–2009 and a forecast for 2050. Ornis Svecica 24: 106–128.

Hagemeijer WJM & Blair MJ (eds). 1997. The EBCC atlas of European breeding birds: their distribution and abundance. T & AD Poyser, London.

Keeling C, Chin J & Whorf T. 1996. Increased activity of northern vegetation inferred from atmospheric CO2 measurements. Nature 382: 146–149.

Lehikoinen A & Virkkala R. 2016. North by north-west: climate change and directions of density shifts in birds. Global Change Biology 22: 1121–1129.

Lehikoinen A, Foppen RPB, Heldbjerg H, Lindström Å, van Manen W, Piirainen S, van Turnhout CAM & Butchart SHM. 2016. Large-scale climatic drivers of regional winter bird population trends. Diversity and Distributions 22: 1163–1173.

Lindström Å, Green M, Paulson G, Smith HG & Devictor V. 2013. Rapid changes in bird community composition at multiple spatial scales in response to recent climate change. Ecography 36: 313–322.

Lindström Å. 2018. Så påverkas fåglarna. Bi-lagan 1/2018: 11–13. Available at

Los SO. 2013. Analysis of trends in fused AVHRR and MODIS NDVI data for 1982–2006 : Indication for a CO2 fertilization effect in global vegetation. Global Biogeochemical Cycles 27: 318–330.

Lundmark H, Josefsson T & Östlund L. 2013. The history of clear-cutting in northern Sweden – driving forces and myths in boreal silviculture. Forest Ecology and Management 307: 112–122.

Martin R, Rochefort J, Mundry R & Segelbacher G. 2019. Delimitation of call types of Red Crossbill (Loxia curvirostra) in the Western Palearctic. Écoscience 26: 177–194.

Munier S, Carrer D, Planque C, Camacho F, Albergel C & Calvet J-C. 2018. Satellite leaf area index: global scale analysis of the tendencies per vegetation type over the last 17 years. Remote Sensing 10: 424.

Odsen SG, Pinzon J, Schmiegelow FKA, Acorn J & Spence JR. 2018. Boreal songbirds and variable retention management: a fifteen-year perspective on avian conservation and forestry. Canadian Journal of Forest Research 48: 1495–1502.

Ottvall R, Edenius L, Elmberg J, Engström H, Green M, Holmqvist N, Lindström Å, Tjernberg M & Pärt T. 2008. Populationstrender för fågelarter som häckar i Sverige. Naturvårdsverket rapport 5813. Available at

Pakkala T, Lindén A, Tiainen J, Tomppo E & Kouki J. 2014. Indicators of forest biodiversity: which bird species predict high breeding bird assemblage diversity in boreal forests at multiple spatial scales? Annales Zoologici Fennici 51: 457–476.

PEFC. 2019. PEFC-certifierad Areal Sverige. Statistik. Retrieved 2 April 2019, from

Poulsen BO. 2002. Avian richness and abundance in temperate Danish forests: tree variables important to birds and their conservation. Biodiversity & Conservation 11: 1551–1566.

Ram D, Axelsson A-L, Green M, Smith HG & Lindström Å. 2017. What drives current population trends in forest birds – forest quantity, quality or climate?-A large-scale analysis from northern Europe. Forest Ecology and Management 385: 177–188.

Roberge J-M & Angelstam P. 2006. Indicator species among resident forest birds – a cross-regional evaluation in northern Europe. Biological Conservation 130: 134–147.

Rosenvald R, Lõhmus A, Kraut A & Remm L. 2011. Bird communities in hemiboreal old-growth forests: the role of food supply, stand structure, and site type. Forest Ecology and Management 262: 1541–1550.

Spearman C. 1904. The proof and measurement of association between two things. American Journal of Psychology 15: 72–101.

Svensson S, Svensson M & Tjernberg M. 1999. Svensk Fågelatlas. Vår Fågelvärld supplement 31. Sveriges Ornitologiska Förening, Stockholm.

Söderström B. 2009. Effects of different levels of green- and dead-tree retention on hemi-boreal forest bird communities in Sweden. Forest Ecology and Management 257: 215–222.

Tjernberg M & Svensson M (eds). 2007. Artfakta – rödlistade ryggradsjur i Sverige. Artdatabanken, SLU, Uppsala.

Virkkala R & Lehikoinen A. 2017. Birds on the move in the face of climate change: High species turnover in northern Europe. Ecology and Evolution 7: 8201–8829.

Wretenberg J, Lindström Å, Svensson S, Thierfelder T & Pärt T. 2006. Population trends of farmland birds in Sweden and England: similar trends but different patterns of agricultural intensification. Journal of Applied Ecology 43: 1110–1120.

WWF. 2018. Living planet report – 2018: Aiming higher. Grooten M & Almond REA (eds). WWF, Gland, Switzerland.

Zhu Z, Piao S, Myneni RB, Huang M, Zeng Z, Canadell JG, Ciais P, Sitch S, Friedlingstein P, Arneth A, Cao C, Cheng L, Kato E, Koven C, Li Y, Lian X, Liu Y, Liu R, Mao J, Pan Y, Peng S, Peñuelas J, Poulter B, Pugh TAM, Stocker BD, Viovy N, Wang X, Wang Y, Xiao Z, Yang H, Zaehle S & Zeng N. 2016. Greening of the Earth and its drivers. Nature Climate Change 6: 791–795.




How to Cite

Ferry, B., Rune, H., Andersson, U., & Green, M. (2020). Increasing numbers of wintering forest birds in Swedish Lapland 1986–2017 show stronger correlations with forest development than with local weather. Ornis Svecica, 30, 13–30.



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