The true cost of partial fencing: evaluating strategies to reduce reptile road mortality

  • Published source details Markle C.E., Gillingwater S.D., Levick R. & Chow-Fraser P. (2017) The true cost of partial fencing: evaluating strategies to reduce reptile road mortality. Wildlife Society Bulletin, 41, 342-350.


This study is summarised as evidence for the following.

Action Category

Install barriers and crossing structures along roads/railways

Action Link
Reptile Conservation
  1. Install barriers and crossing structures along roads/railways

    A before-and-after study in 2003–2014 in a wetland complex in Ontario, Canada (Markle et al. 2017) found that adding roadside fencing and culverts reduced turtle and snake abundances on a causeway, although only along completely fenced sections of road, and use of culverts by individuals was low. In areas that were fully fenced, the number of turtle or snakes found on the causeway was lower after fencing than before (turtles: after fencing: 2, before fencing: 10; snakes: after: 3, before: 7), but remained similar in partially fenced areas (turtles: 3; snakes: 3–4) and areas with no fencing (turtles: 1–2; snakes: 2). Two of 68 Blanding’s turtles Emydoidea blandingii and none of 30 spotted turtles Clemmys guttata used one of seven culverts. One of 30 radio-tracked Blanding’s turtle used a culvert once. Reptiles were surveyed in April–October on a causeway (3.6 km long) across a marsh for five years (2003–2007: 22 surveys/month, 154 total surveys) before post-and-mesh-net fencing was installed in 2008–2009 and for five years afterwards (in 2010–2014: 40 surveys/month, 284 total surveys). After exclusion fencing was built, road sections were classified as: fully fenced, partially fenced, or unfenced. In 2012–2014, seven culverts were added to the causeway. In 2014–2015, culvert use was monitored by cameras, an automated PIT-tag checker at culvert entrances (68 Blanding’s and 30 spotted turtles were PIT-tagged) and radio-tracking turtles (30 additional Blanding’s turtles were radio-tracked once a week during active seasons).

    (Summarised by: Katie Sainsbury)

Output references
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