DNA Footprints: Using Parasites to Detect Elusive Animals, Proof of Principle in Hedgehogs

Area of Science:

• Veterinary Parasitology
• Molecular Ecology
• Wildlife Conservation

Background:

• The Western European Hedgehog (Erinaceous europaeus) population is declining across Europe.
• Current monitoring methods for hedgehogs are subjective and prone to error.
• Accurate population trend estimation is crucial for conservation efforts.

Purpose of the Study:

• To develop an objective method for detecting hedgehog presence using their specific parasites.
• To validate the use of parasitic nematode DNA in gastropods as an indicator for hedgehog populations.
• To establish a novel tool for supplementing existing wildlife survey techniques.

Main Methods:

• Collected gastropods (slugs) from two sites with known hedgehog presence/absence.
• Extracted DNA from gastropods and used a novel, highly specific PCR-based multiplex assay.
• Targeted the second internal transcribed spacer of parasite ribosomal DNA for species identification.

Main Results:

• The parasitic nematode *Crenosoma striatum*, specific to hedgehogs, was detected in gastropods only at the site with hedgehogs.
• The molecular test demonstrated high specificity, clearly differentiating between *C. striatum* and *Crenosoma vulpis*.
• Parasite DNA was found in gastropods with an average prevalence of 10% during spring and autumn.

Conclusions:

• Detection of specific parasite DNA in intermediate hosts (gastropods) confirms the presence of elusive definitive hosts like hedgehogs.
• This method offers an adaptable and objective alternative to traditional, error-prone wildlife monitoring.
• The approach shows significant potential for improving ecological survey methods for nocturnal species.