Skip to main content

Temporal patterns of wild boar-vehicle collisions in Estonia, at the northern limit of its range


Collisions with large ungulates are considered to be a serious problem in many countries over the world. These incidents create a rising concern in traffic safety and cause extensive ecological and economical damage. In this paper, we investigate temporal distribution of wild boar-related traffic accidents—seasonal, weekday and diurnal patterns. We analysed 918 collision reports collected by Estonian environmental emergency hotline, police and insurance companies during 2004–2013. Notable increase in wild boar abundance and harvest numbers appeared during the study period, leading not only to higher road collision risk but also having been referred to African swine fever emergence in the area. Our results suggest that the highest risk for collision is in October, November and December. More wild boar-vehicle collisions (WBVCs) occur during weekends with a peak on Friday probably due to higher traffic volumes. Regarding diurnal patterns, most of WBVCs occur after sunset, and the frequency of collisions remains high until late night. Knowledge about temporal patterns of WBVCs is important, as it may help to improve suitable mitigation measures.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2


  1. Balčiauskas L, Balčiauskienė L (2008) Wildlife–vehicle accidents in Lithuania, 2002–2007. Acta biol univ Daugavpil 8(1):89–94

    Google Scholar 

  2. Boitani L, Mattei L, Nonis D, Corsi F (1994) Spatial and activity patterns of wild boars in Tuscany, Italy. J Mammal 75:600–612

    Article  Google Scholar 

  3. Dussault C, Poulin M, Courtois R, Ouellet J-P (2006) Temporal and spatial distribution of moose-vehicle accidents in the Laurentides Wildlife Reserve, Quebec, Canada. Wildl Biol 12(4):415–425

    Article  Google Scholar 

  4. Estonian Environment Agency (2014) Aastaraamat Mets 2013. (Yearbook Forest 2013. In Estonian). Available at Accessed 22 December 2015

  5. Estonian Road Administration (2014) Aastaraamat 2014. (Yearbook 2014. In Estonian). Available at Accessed 22 December 2015

  6. Groot Bruinderink GWTA, Hazebroek E (1996) Ungulate traffic collisions in Europe. Conserv Biol 10:1059–1067

    Article  Google Scholar 

  7. Hothorn T, Müller J, Held L, Möst L, Mysterud A (2015) Temporal patterns of deer-vehicle collisions consistent with deer activity pattern and density increase but not general accident risk. Accid Anal Prev 81:143–152

    Article  PubMed  Google Scholar 

  8. Järv O, Ahas R, Saluveer E, Derudder B, Witlox F (2012) Mobile phones in a traffic flow: a geographical perspective to evening rush hour traffic analysis using call detail records. PLoS ONE 7(11):e49171. doi:10.1371/journal.pone.0049171

    Article  PubMed  PubMed Central  Google Scholar 

  9. Kaal L, Metlitski S, Jentson M, Teder A (2014) Liiklusloenduse tulemused 2013. aastal. (Results of traffic counts in 2013. In Estonian). AS Teede Tehnokeskus, Tallinn

    Google Scholar 

  10. Koonik V (2008) Tallinn-Tartu-Võru-Luhamaa põhimaanteel üle 12 m pikkuste sõidukite ja autorongide liikluse reedeti kella 13.00-st kuni kella 20.00-ni kehtinud piirangu (eksperimendi) analüüs. (Analysis of experimental road usage restriction for vehicles over a length of 12 m and road trains on Fridays from 13:00 to 20:00. In Estonian). Estonian Road Administration. Available at Accessed 22 December 2015

  11. Lagos L, Picos J, Valero E (2012) Temporal pattern of wild ungulate-related traffic accidents in northwest Spain. Eur J Wildl Res 58:661–668

    Article  Google Scholar 

  12. Mardiste M (1992) Liiklusõnnetused metsloomadega. (Traffic accidents related to wild animals. In Estonian). Eesti Loodus 5:290–295

    Google Scholar 

  13. Massei G, Kindberg J, Licoppe A, Gačić D, Šprem N, Kamler J, Baubet E, Hohmann U, Monaco A, Ozolinš J, Cellina S, Podgórski T, Fonseca C, Markov N, Pokorny B, Rosell C, Náhlik A (2014) Wild boar populations up, numbers of hunters down? A review of trends and implications for Europe. Pest Manag Sci 71:492–500

    Article  Google Scholar 

  14. Morelle K, Lehaire F, Lejeune P (2013) Spatio-temporal patterns of wildlife-vehicle collisions in a region with a high-density road network. Nat Conserv 5:53–73

    Article  Google Scholar 

  15. Neumann W, Ericsson G, Dettki H, Bunnefeld N, Keuler NS, Helmers DP, Radeloff VC (2012) Difference in spatiotemporal patterns of wildlife road-crossings and wildlife-vehicle collisions. Biol Conserv 145:70–78

    Article  Google Scholar 

  16. Nurmoja I (2016) Sigade Aafrika katk—uuringutest ja tulemustest. (African swine fever—research and results. Presentation for hunters. In Estonian). Estonian Veterinary and Food Laboratory. Available at Accessed 17 June 2016

  17. Oja R, Kaasik A, Valdmann H (2014) Winter severity or supplementary feeding – which matters more for wild boar? Acta Theriol 59:553–559

    Article  Google Scholar 

  18. Oļševskis E, Guberti V, Seržants M, Westergaard J, Gallardo C, Rodze I, Depner K (2016) African swine fever virus introduction into the EU in 2014: experience of Latvia. Res Vet Sci 105:28–30

    Article  PubMed  Google Scholar 

  19. Putzu N, Bonetto D, Civallero V, Fenoglio S, Meneguz PG, Preacco N, Tizziani P (2014) Temporal patterns of ungulate-vehicle collisions in a subalpine Italian region. Ital J Zool 81:463–470

    Article  Google Scholar 

  20. R Core Team (2014) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna,

    Google Scholar 

  21. Rodríguez-Morales B, Díaz-Varela ER, Marey-Pérez MF (2013) Spatiotemporal analysis of vehicle collisions involving wild boar and roe deer in NW Spain. Accid Anal Prev 60:121–133

    Article  PubMed  Google Scholar 

  22. Romin LA, Bissonette JA (1996) Deer-vehicle collisions: status of state monitoring activities and mitigation efforts. Wildl Soc Bull 24:276–283

    Google Scholar 

  23. Statistics Estonia (2015) Statistical database. Available at Accessed 22 December 2015

  24. Steiner W, Leisch F, Hackländer K (2014) A review on the temporal pattern of deer-vehicle accidents: impact of seasonal, diurnal and lunar effects in cervids. Accid Anal Prev 66:168–181

    Article  PubMed  Google Scholar 

  25. Thurfjell H, Spong G, Olsson M, Ericsson G (2015) Avoidance of high traffic levels results in lower risk of wild boar-vehicle accidents. Landsc Urban Plan 133:98–104

    Article  Google Scholar 

  26. Valero E, Picos J, Álvarez X (2015) Road and traffic factors correlated to wildlife-vehicle collisions in Galicia (Spain). Wildl Res 42:25–34

    Article  Google Scholar 

  27. van Emden HF (2008) Statistics for terrified biologists. Blackwell Publishing Ltd, UK

    Google Scholar 

  28. Veeroja R, Männil P (2014) Population development and reproduction of wild boar (Sus scrofa) in Estonia. Wildl Biol Pract 10(3):17–21

    Google Scholar 

  29. Zuberogoitia I, del Real J, Torres JJ, Rodríguez L, Alonso M, Zabala J (2014) Ungulate vehicle collisions in a peri-urban environment: consequences of transportation infrastructures planned assuming the absence of ungulates. PLoS ONE 9(9):e107713. doi:10.1371/journal.pone.0107713

    Article  PubMed  PubMed Central  Google Scholar 

Download references


This research was supported by the project IUT2-16 ‘Global Warming and Material Cycling in Landscapes. Global Warming- and Human-Induced Changes of Landscape Structure and Functions: Modelling and Ecotechnological Regulation of Material Fluxes in Landscapes’, financed by the Estonian Research Council.

We are grateful to the Estonian Environmental Inspectorate and Estonian Road Administration for providing the collision data. Special thanks to Villu Lükk and Sirje Lilleorg from the Estonian Road Administration for their useful comments about the data, and the anonymous reviewers for constructive criticism on an earlier draft of this manuscript. We would also like to thank all road users, hunters and police officers who have reported collisions or animal carcasses on the road.

Author information



Corresponding author

Correspondence to Maris Kruuse.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Online Resource 1

(JPG 128 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Kruuse, M., Enno, SE. & Oja, T. Temporal patterns of wild boar-vehicle collisions in Estonia, at the northern limit of its range. Eur J Wildl Res 62, 787–791 (2016).

Download citation


  • Road ecology
  • Wild boar-vehicle collisions
  • Temporal patterns
  • Traffic safety