Towards more efficient large-scale DNA-based detection of terrestrial mammal predators from scats
The DNA detection of wildlife from environmental samples has the potential to contribute significantly to wildlife management and ecological research. In terrestrial ecosystems, much work has focused on the identification of mammal predators from faecal (scat) samples. However, the relatively high time and financial costs of collecting and analysing scat DNA remain barriers to more widespread implementation of such DNA detection methods, especially for high-throughput surveys. Here, we evaluate methods used for DNA extraction from scats, as applied to detection of the Australian red fox, an introduced predator. We compare the relative costs of two approaches: the method previously used to screen thousands of scat samples in surveys over several years, and a modified version which involves swabbing scats at the time of collection and using a mechanised liquid handling platform to extract DNA from the swabs. We demonstrate that mechanised DNA extraction from swabs is more efficient than manual DNA extraction from whole scats, in terms of both time and resources. This provides a means for rapid, high-throughput screening of scats for the presence of mammal predators, enabling time-effective management responses to non-invasive surveys.
KeywordsDNA detection Environmental DNA Faecal DNA Non-invasive sampling Predator faeces Trace DNA
Thanks to Elise Dewar, Catriona Campbell, Elodie Modave, and staff and volunteers from the Department of Primary Industries, Parks, Water and Environment, Tasmania, for help with sample collection. Sam Ryan assisted with laboratory analyses and Aaron Adamack assisted with data analysis. Thanks to two anonymous reviewers for their useful suggestions.
Conflict of interest
The authors declare that they have no conflict of interest.
This study was partly funded by the Invasive Animals Cooperative Research Centre project 1.L.21.
Compliance with ethical standards
This article does not contain any studies with human participants or animals performed by any of the authors.
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