Using eDNA to construct community assemblages of amphibians at sites infected with Batrachochytrium salamandrivorans in the Netherlands.

Davison, A

Abstract

Amphibians worldwide are in decline with one of the main culprits being the fungal disease chytridiomycosis. This fungus affects the skin of amphibians, leading to excessive skin shedding or skin lesions which, in many cases, result in death. The recently discovered Batrachochytrium salamandrivorans (Bsal) fungus, which only affects salamanders and newts (urodelans), has currently only spread to a few countries in Europe past its native range in Asia. However, Bsal has been shown to cause high mortality rates in some European urodelans and has the potential to spread much further across the continent. For this reason, monitoring the spread of the disease and the species threatened with infection is essential in mitigating the damage Bsal may cause. Utilising environmental DNA (eDNA) metabarcoding is a relatively new and effective method of monitoring biodiversity, especially elusive species. Thus the aims of this study are to 1.) validate the use of two different metabarcoding primers and single-species approaches in detecting amphibian species with eDNA in the Netherlands and 2.) investigate the relationship between Bsal and the amphibian species present at a site in Gelderland, Netherlands. Bufo bufo, Lissotriton vulgaris, Pelobates fuscus, Pelophylax spp. and Rana temporaria were detected by both the 12S-V5 vertebrate and the 16S amphibian universal primer sets used in this study with the 12S-V5 primers also detecting Triturus cristatus. The detection of amphibians by these two primer sets were compared, with the 12S-V5 vertebrate primers proving more suitable for use in this capacity. The vertebrate primers were then compared to single-species qPCR approaches for two protected amphibian species: Triturus cristatus (great crested newt) and Pelobates fuscus (spadefoot toad). The single-species approach outperformed the metabarcoding primer set, detecting both species more often. After testing the vertebrate primer set data with distance-based redundancy analysis, no significant relationship between Bsal presence and the amphibian community composition was found but further data is needed to confirm this finding. Potential amphibian or waterbird vectors of Bsal are explored and future avenues for research are discussed. This research provides the foundation for future studies on Bsal and its relationship with amphibian communities and helps inform researchers on correct primer selection for work with amphibians in Europe.

• Thesis Type: Dissertation
• Deposit Date: Aug 2, 2022
• Publicly Available Date: Jul 2, 2024
• Award Date: Apr 1, 2022