Nesting success and barrier breaching: assessing the effectiveness of roadway fencing in diamondback terrapins (Malaclemys terrapin)

  • Published source details Reses H.E., Davis Rabosky A.R. & Wood R.C. (2015) Nesting success and barrier breaching: assessing the effectiveness of roadway fencing in diamondback terrapins (Malaclemys terrapin). Herpetological Conservation and Biology, 10, 161-179.


This study is summarised as evidence for the following.

Action Category

Install barriers along roads/railways

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

    A replicated study in 2011–2012 along two roadside verges across salt marshes in New Jersey, USA (Reses et al. 2015) found that where barriers were installed, diamondback terrapins Malaclemys terrapin nested more often on the marsh-side of barriers than on the road-side, and that terrapins were less likely to breach barriers with smaller gaps at the bottom. After barrier fences were installed, diamondback terrapins laid more nests on the marsh-side of the fence than on the road-side (results presented as statistical model outputs, see original paper for details). In separate arena trials, diamondback terrapins were less likely to breach fences with smaller gaps at the bottom (0 cm gap: 10% breached; 3–5 cm: 37–60 %; 6–8 cm: 96–100%). In 2011 and 2012, sections of two causeways (589–623 m long) with corrugated tubing fencing (15 cm diameter) were surveyed on foot for terrapin nests. Surveys were carried out every week in June–July 2011 and twice in June–July 2012. Trials to test whether terrapins could breach the fences with different sized gaps at the bottom (0–8 cm) were carried out in a fenced enclosure with 40 individual terrapins (total of 74 trial).

    (Summarised by: Katie Sainsbury)

Output references
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