Protect nests and nesting sites from predation using visual deterrents

How is the evidence assessed?
  • Effectiveness
    not assessed
  • Certainty
    not assessed
  • Harms
    not assessed

Study locations

Key messages

  • One study evaluated the effects of protecting nests and nesting sites from predation using visual deterrents on reptile populations. This study was in Australia.



  • Reproductive success (1 study): One replicated, controlled study in Australia found that a similar number of loggerhead turtle nests marked with red flags were predated compared to those marked only with wooden stakes.


About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A replicated, controlled study in 2014–2015 at one beach in south-eastern Queensland, Australia (Lei & Booth 2017) found that using red flags as a visual deterrent to predators of loggerhead turtle Caretta caretta nests did not reduce nest predation. The number of predated nests did not differ significantly between those marked with red flags (7 out of 10) and those marked with wooden stakes (10 out of 11). Yellow-spotted goannas Varanus panoptes were the most common predator of nests. In May 2014–June 2015, ten nests were each marked with a bright red canvas flag (30 x 40 cm) mounted on a 1.2 m high stake inserted 50 cm into the sand, 30 cm to the side of the nest. A further 11 nests were marked with only a wooden stake. All nests were visited daily in early December to the end of February 2014–2016 to record predation events.

    Study and other actions tested
Please cite as:

Sainsbury K.A., Morgan W.H., Watson M., Rotem G., Bouskila A., Smith R.K. & Sutherland W.J. (2021) Reptile Conservation: Global Evidence for the Effects of Interventions for reptiles. Conservation Evidence Series Synopsis. University of Cambridge, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

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Reptile Conservation

This Action forms part of the Action Synopsis:

Reptile Conservation
Reptile Conservation

Reptile Conservation - Published 2021

Reptile synopsis

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