Deer-vehicle crashes: Extensive peak at 1 hour after sunset

https://doi.org/10.1016/S0749-3797(01)00352-XGet rights and content

Abstract

Background: On-road encounters with animals resulted in 231 fatalities in the United States in 1999, and the annual number of deer-vehicle crashes (DVCs) has been estimated to total more than 500,000. Previous studies suggest that the number of DVCs is highest during the hours of dusk and dawn. However, these studies have not adequately taken into account the synchronization of visibility and animal behavior with sunset and sunrise. The goal of this study was to determine the temporal variation in the crash risk, so that this variation could be better taken into account by road users.

Methods: In Finland, the recorded times for 13,379 crashes with moose and 8191 crashes with white-tailed deer were adjusted to sunset and sunrise according to the location and date of occurrence. In addition, two sample distributions of traffic volume on public roads were adjusted to sunset. The DVC rate was computed as the proportion of number of crashes to traffic volume.

Results: The highest crash peak occurred 1 hour after sunset for both species of deer. The relative risk peaked at 30 times the seasonal daytime level of the crash rate for white-tailed deer in the fall and at over 60 times for moose in the summer.

Conclusions: Drivers can effectively reduce their risk of DVCs by reducing speed and remaining alert for deer intrusions on the roadway during the most critical time of the day: after sunset.

Section snippets

Methods

The original database was compiled by the Finnish National Road Administration and consisted of 21,887 DVCs that occurred in Finland between 1989 and 1997. The crash data included, among other variables, the exact time of the event, exact location, and an indication of the deer species (either a moose or “other deer”) reported by the police. As the damage resulting from a collision with a deer is partially compensated for by the state, the coverage of the DVC data is estimated to be high,

Results

Figure 2 presents the distribution of DVCs at the time of sunset and sunrise in the southwestern study area. The number of crashes increases sharply approximately 1 to 2 hours before sunset and peaks, throughout the year, at 1 hour after sunset for both species of deer. In the southwestern study area, 46% of the moose-vehicle crashes and 37% of the crashes involving white-tailed deer occurred during the first 3 hours after sunset. The proportion of the crashes taking place during this 3-hour

Discussion

Our analyses showed that the DVCs were highly concentrated in the first 2 to 3 hours after sunset and, more remarkably, that the variation in the crash rate was extensive even within this relatively short period. This extraordinary phenomenon is apparently an outcome of several factors directly and indirectly related to sunset that affect both the quantity and quality of the encounters between deer and motor vehicles.

Obviously, increasing darkness affects the driver’s ability to detect a deer

Conclusions

These results show that a large proportion of DVCs occur just after sunset. Such high concentration of crashes—a “black spot”34—makes countermeasures focused on reducing the peak more cost effective and thus more practical both for society and for individual road users. Drivers can reduce crash risk and especially the risk of serious consequences by lowering their speed11 and by keeping alert for deer during the relatively short period of the peak.35 Knowledge of the high-risk period should

Acknowledgements

We are grateful to Juhani Mänttäri, Finnish National Road Administration; Tuire and Kaarlo Nygrén, Finnish Game and Fisheries Research Institute; and Reijo Orava, Finnish Hunters’ Central Organization for contributing their knowledge and ideas. This research was supported by the Finnish Ministry of Transport and Communications.

References (35)

  • T.M Farrell et al.

    Moose-motor vehicle collisionsan increasing hazard in northern New England

    Arch Surg

    (1996)
  • S Lavsund et al.

    Moose-vehicle relations in Swedena review

    Alces

    (1991)
  • Raportti Kymen läänin liikennevahinkojen tutkijalautakunnan tutkimista hirvieläinvahingoista vuosina 1977–1979 [Report...
  • E.A Allen et al.

    Deer-car accidents in Southern Michigan

    J Wildlife Manag

    (1976)
  • Almkvist B, Andre T, Ekblom S, Rempler S-A. Viltolycksprojektet, Slutrapport. [Traffic accidents with wild animals,...
  • J Aschoff

    Circadian activity pattern with two peaks

    Ecology

    (1966)
  • G Cederlund et al.

    Winter activity patterns of females in two moose populations

    Can J Zoology

    (1989)
  • Cited by (0)

    View full text