Study

Integrated analysis for population estimation, management impact evaluation, and decision-making for a declining species

  • Published source details Crawford B.A., Moore C.T., Norton T.M. & Maerz J.C. (2018) Integrated analysis for population estimation, management impact evaluation, and decision-making for a declining species. Biological Conservation, 222, 33-43.

Actions

This study is summarised as evidence for the following.

Action Category

Use signage to warn motorists about wildlife presence

Action Link
Reptile Conservation

Install barriers along roads/railways

Action Link
Reptile Conservation
  1. Use signage to warn motorists about wildlife presence

    A before-and-after study in 2009–2015 on saltmarsh in Georgia, USA (Crawford et al. 2018) found that adding a flashing terrapin-warning sign to alert motorists and partially fencing a causeway reduced the likelihood of mortality for diamondback terrapins Malaclemys terrapin crossing the road. When the flashing signs and hybrid nestbox-fence barrier were installed on a road, survival of crossing female diamondback terrapins increased from 24% to 53% (data reported as statistical model outputs). In 2011, a 22 m hybrid nestbox-fence barrier was built along a 9 km long causeway. In 2013, two terrapin crossing signs with flashing warning beacons were added to warn motorists entering a 6 km stretch of causeway. The signs were activated for 2 hours/day during peak terrapin crossing times. Terrapins were surveyed on the causeway and in adjacent creeks during the nesting season (May–July) in 2009–2015.

    (Summarised by: Katie Sainsbury)

  2. Install barriers along roads/railways

    A before-and-after study in 2009–2015 on a causeway over a saltmarsh in Georgia, USA (Crawford et al. 2018, same experimental set-up as Crawford et al. 2017) found that installing a roadside barrier with nest boxes and adding a flashing terrapin-warning sign to alert motorists reduced likelihood of mortality for diamondback terrapin Malaclemys terrapin crossing the road. When the hybrid nestbox-fence barrier and flashing signs were added to a road, survival of crossing female diamondback terrapins increased from 24% to 53% (data reported as statistical model outputs). In 2011, a 22 m long hybrid nestbox-fence barrier was built along an 8.7 km long causeway. In 2013, two terrapin crossing signs with flashing warning beacons were added to warn motorists entering a 6 km stretch of causeway. The signs were activated for 2 hours/day during peak terrapin crossing times. Terrapins were surveyed on the causeway and in adjacent creeks during the nesting season (May–July) in 2009–2015.

    (Summarised by: Katie Sainsbury)

Output references
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