COVID-19 related travel restrictions prevented numerous wildlife deaths on roads: A comparative analysis of results from 11 countries

Abstract

Millions of wild animals are killed annually on roads worldwide. During spring 2020, the volume of road traffic was reduced globally as a consequence of the COVID-19 pandemic. We gathered data on wildlife-vehicle collisions (WVC) from Czechia, Estonia, Finland, Hungary, Israel, Norway, Slovenia, Spain, Sweden, and for Scotland and England within the United Kingdom. In all studied countries WVC statistics tend to be dominated by large mammals (various deer species and wild boar), while information on smaller mammals as well as birds are less well recorded. The expected number of WVC for 2020 was predicted on the basis of 2015-2019 WVC time series representing expected WVC numbers under normal traffic conditions. Then, the forecasted and reported WVC data were compared. The results indicate varying levels of WVC decrease between countries during the COVID-19 related traffic flow reduction (CRTR). While no significant change was determined in Sweden, where the state-wide response to COVID-19 was the least intensive, a decrease as marked as 37.4% was identified in Estonia. The greatest WVC decrease, more than 40%, was determined during the first weeks of CRTR for Estonia, Spain, Israel, and Czechia. Measures taken during spring 2020 allowed the survival of large numbers of wild animals which would have been killed under normal traffic conditions. The significant effects of even just a few weeks of reduced traffic, help to highlight the negative impacts of roads on wildlife mortality and the need to boost global efforts of wildlife conservation, including systematic gathering of roadkill data.

Keywords: COVID-19 lockdown; Mesocarnivores; Traffic flow; Ungulates; Wildlife crash reporting systems; Wildlife-vehicle collisions.

Fig. 1

An average weekly distribution of WVC (in %) aggregated over period 2015–2019 (2017–2019 for FIN and HUN) for the respective weeks. Vertical lines indicate the period of CRTR (11th – 26th week).

Fig. 2

Relative decrease (%) in traffic flow during the CRTR period for 11 countries in relation to the same week of 2019 (CZE, ESP, EST, FIN, HUN, NOR, SVN, SWE) or the 10th week of 2020 when records for 2019 were not available (ENG, SCO) or the 9th week (ISR; national holidays in the 10th). For a description of data see Appendix A. Data for week 16 in NOR were not available (we used linear interpolation of the neighbouring values, see the dashed part of the respective curve). Relative decrease (%) in traffic flow during the CRTR period for 11 countries in relation to the same week of 2019 (CZE, ESP, EST, FIN, HUN, NOR, SVN, SWE) or the 10th week of 2020 when records for 2019 were not available (ENG, SCO) or the 9th week (ISR; national holidays in the 10th). For a description of data see Appendix A. Data for week 16 in NOR were not available (we used linear interpolation of the neighbouring values, see the dashed part of the respective curve).

Fig. 3

A flow chart indicating the procedure of WVC difference estimation.

Fig. 4

An estimate of WVC reduction (%) during CRTR (11th–26th week in 2020) in relation to expected WVC. WVC reduction was calculated for periods of X^th week to Y^th week, where X = 11 (CZE, ESP, EST, FIN, HUN, ISR, NOR, SVN) or X = 12 (ENG, SCO, SWE; their CRTR period is one week shorter), and Y varies from X to 26. The dots represent statistically significant values. Detailed figures for each country can be found in Appendix C. An estimate of WVC reduction (%) during CRTR (11th–26th week in 2020) in relation to expected WVC. WVC reduction was calculated for periods of X^th week to Y^th week, where X = 11 (CZE, ESP, EST, FIN, HUN, ISR, NOR, SVN) or X = 12 (ENG, SCO, SWE; their CRTR period is one week shorter), and Y varies from X to 26. The dots represent statistically significant values. Detailed figures for each country can be found in Appendix C.