Evaluation of wildlife reflectors in reducing vehicle-deer collisions on Indiana Interstate 80/90

  • Published source details Gulen S., McCabe G. & Wolfe S.E. (2000) Evaluation of wildlife reflectors in reducing vehicle-deer collisions on Indiana Interstate 80/90. Unpublished report, Indiana Department of Transportation report, FHWA/IN/JTRP-2006/18.


This study is summarised as evidence for the following.

Action Category

Install wildlife warning reflectors along roads

Action Link
Terrestrial Mammal Conservation
  1. Install wildlife warning reflectors along roads

    A replicated, randomized, controlled study in 1999–2005 along a highway in Indiana, USA (Gulen et al. 2000) found that wildlife reflectors reduced deer-vehicle collisions by 19% overall, but there was no difference between different reflector colours, spacing or design. When reflector sites were combined and compared with sites without reflectors, there was a 19% reduction in deer-vehicle collisions with reflector use. However, there was no significant difference in numbers of collisions between different reflector combinations (colours, spacing, single/dual design, reflectors on central reservation or not) or between each reflector combination and sites without reflectors. The greatest decrease in collisions was associated with 30-m reflector spacing regardless of colour or design. In 1999, two replicates of 16 treatment combinations (randomized order) were installed along two 1.6-km-long road sections. Treatments were different reflector colour (red and blue/green), spacing (30 m and 45 m), design (single and dual reflectors) and whether or not the central reservation also had reflectors. There was a 1.6-km control section without reflectors at each end of each replicate. Numbers of deer-vehicle collisions were recorded in April–May and October–November in 1999–2005.

    (Summarised by: Rebecca K. Smith)

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